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Lane MR, Lowe A, Vukcevic J, Clark RG, Madani G, Higgins DP, Silver L, Belov K, Hogg CJ, Marsh KJ. Health Assessments of Koalas after Wildfire: A Temporal Comparison of Rehabilitated and Non-Rescued Resident Individuals. Animals (Basel) 2023; 13:2863. [PMID: 37760263 PMCID: PMC10525633 DOI: 10.3390/ani13182863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 08/25/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023] Open
Abstract
Many koalas (Phascolarctos cinereus) required rehabilitation after the 2019/20 Australian megafires. Little is known about how the post-release health of rehabilitated koalas compares to non-rescued resident koalas. We evaluated health parameters in rehabilitated koalas and resident koalas in burnt and unburnt habitat in southern New South Wales, Australia. Health checks were undertaken within six weeks of fire (rehabilitated group), 5-9 months post-fire and 12-16 months post-fire. Body condition improved significantly over time in rehabilitated koalas, with similar condition between all groups at 12-16 months. Rehabilitated koalas therefore gained body condition at similar rates to koalas who remained and survived in the wild. The prevalence of Chlamydia pecorum was also similar between groups and timepoints, suggesting wildfire and rehabilitation did not exacerbate disease in this population. While there was some variation in measured serum biochemistry and haematology parameters between groups and timepoints, most were within normal reference ranges. Our findings show that koalas were generally healthy at the time of release and when recaptured nine months later. Landscapes in the Monaro region exhibiting a mosaic of burn severity can support koalas, and rehabilitated koala health is not compromised by returning them to burnt habitats 4-6 months post-fire.
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Affiliation(s)
- Murraya R. Lane
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia;
| | - Arianne Lowe
- Stromlo Veterinary Services, P.O. Box 3963, Weston, ACT 2611, Australia;
| | | | - Robert G. Clark
- Research School of Finance, Actuarial Studies and Statistics, The Australian National University, Canberra, ACT 2601, Australia;
| | - George Madani
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia;
| | - Damien P. Higgins
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Luke Silver
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia; (L.S.); (K.B.); (C.J.H.)
| | - Katherine Belov
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia; (L.S.); (K.B.); (C.J.H.)
| | - Carolyn J. Hogg
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia; (L.S.); (K.B.); (C.J.H.)
| | - Karen J. Marsh
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia;
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2
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Chen CJ, Casteriano A, Green AC, Govendir M. A retrospective study on antibacterial treatments for koalas infected with Chlamydia pecorum. Sci Rep 2023; 13:12670. [PMID: 37542093 PMCID: PMC10403558 DOI: 10.1038/s41598-023-39832-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 07/31/2023] [Indexed: 08/06/2023] Open
Abstract
Chlamydiosis remains the leading infectious disease and is one of the key factors responsible for the dramatic reduction of koala populations in South-East Queensland (SEQ) and New South Wales (NSW) regions of Australia. Possible infection outcomes include blindness, infertility, painful cystitis, and death if left untreated. Studies have reported the treatment efficacy of chloramphenicol and doxycycline, which are the two most commonly administered treatments in diseased koalas, in clinical settings. However, none have directly compared the treatment efficacy of these antibacterials on koala survival. A retrospective study was essential to identify any relationships between the demographical information, and the animals' responses to the current treatment regimens. Associations were explored between six explanatory (sex; maturity; location; clinical signs, treatment; treatment duration) and two outcome variables (survival; post-treatment PCR). Results showed that female koalas had a statistical trend of lower odds of surviving when compared to males (OR = 0.36, p = 0.05). Koalas treated with chloramphenicol for ≥ 28 days had greater odds of surviving than when treated for < 28 days (OR = 8.8, p = 0.02), and those koalas administered doxycycline had greater odds of testing PCR negative when compared to chloramphenicol treatments (OR = 5.45, p = 0.008). There was no difference between the antibacterial treatments (chloramphenicol, doxycycline, and mixed/other) and the survival of koalas. Female koalas had greater odds of exhibiting UGT signs only (OR = 4.86, p < 0.001), and also greater odds of having both ocular and UGT clinical signs (OR = 5.29, p < 0.001) when compared to males. Of the koalas, 28.5% initially had no clinical signs but were PCR positive for C. pecorum. This study enables further understanding of the complex nature between chlamydial infection and response to antibacterial treatment.
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Affiliation(s)
- Chien-Jung Chen
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, Australia.
| | - Andrea Casteriano
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, Australia
| | - Alexandra Clare Green
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, Australia
| | - Merran Govendir
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, Australia
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Charalambous R, Narayan E. A 29-year retrospective analysis of koala rescues in New South Wales, Australia. PLoS One 2020; 15:e0239182. [PMID: 33112860 PMCID: PMC7592758 DOI: 10.1371/journal.pone.0239182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 09/01/2020] [Indexed: 11/18/2022] Open
Abstract
The koala (Phascolarctos cinereus) is currently listed by both the IUCN and the Australian Governments' Threatened Species Scientific Committee as vulnerable to extinction with an overall decreasing population trend. It is unknown exactly how many koalas remain in the wild, but it is known that habitat fragmentation and bushfires have ultimately contributed to the decline of the koala all over Australia. This novel study is a retrospective analysis of data over a 29-year period (1989-2018) using records for 12,543 sightings and clinical care admissions for wild koalas from the major koala hot-spots (Port Stephens, port Macquarie and Lismore) in New South Wales, Australia. This study aims to understand the long-term patterns and trends of key stressors that are contributing to the decline of koalas in New South Wales, and the synergic interactions of factors such as rescue location, sex and age of the koala, and if their decline is influenced progressively by year. The main findings of this retrospective analysis indicated that between all 3 rescue sites, the most common prognosis was disease, the most common disease was signs of chlamydia, and the most common outcome was release. The location where the highest number of koalas were found prior to being reported as sighted or admitted into clinical care was within the regional area of Lismore. Furthermore, sex was not a discriminating factor when it came to prognosis or outcome, but age was significant. Finally, incidents of disease were found to increase over long-term, whereas release decreased over time and euthanasia increased. The wealth of data available to us and the retrospective analysis enabled us in a way to 'zoom out' and reveal how the key environmental stressors have fluctuated spatially and temporally. In conclusion, our data provides strong evidence of added pressures of increased human population growth in metropolitan zones, which increases risks of acute environmental trauma and proximate stressors such as vehicle collisions and dog-attacks as well as increased sightings of virtually healthy koalas found in exposed environments. Thus our 'zoom out' approach provides support that there is an urgent need to strengthen on-ground management, bushfire control regimes, environmental planning and governmental policy actions that should hopefully reduce the proximate environmental stressors in a step wise approach. This will ensure that in the next decade (beyond 2020), NSW koalas will hopefully start to show reversed trends and patterns in exposure to environmental trauma and disease, and population numbers will return towards recovery and stability.
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Affiliation(s)
- Renae Charalambous
- School of Science, Western Sydney University, Penrith, New South Wales, Australia
- School of Agriculture and Food Sciences, Faculty of Science, The University of Queensland, St Lucia, Queensland, Australia
| | - Edward Narayan
- School of Science, Western Sydney University, Penrith, New South Wales, Australia
- School of Agriculture and Food Sciences, Faculty of Science, The University of Queensland, St Lucia, Queensland, Australia
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland, Australia
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4
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Lizárraga D, Timms P, Quigley BL, Hanger J, Carver S. Capturing Complex Vaccine-Immune-Disease Relationships for Free-Ranging Koalas: Higher Chlamydial Loads Are Associated With Less IL17 Expression and More Chlamydial Disease. Front Vet Sci 2020; 7:530686. [PMID: 33102563 PMCID: PMC7546032 DOI: 10.3389/fvets.2020.530686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 08/21/2020] [Indexed: 11/16/2022] Open
Abstract
Background: Chlamydial disease is a major factor negatively affecting koala populations. Vaccination is a promising management option that would result in immune-mediated protection against disease. Measuring and assessing vaccine efficacy can be challenging owing to both direct and indirect interactions caused by vaccination. In this study, we investigate vaccine-immune-chlamydial load-disease relationships from MOMP (major outer membrane protein) vaccine trials to protect healthy free-ranging koalas against Chlamydia-related diseases. Methods: We created a priori hypotheses based on data sources and perceived direct and indirect interactions from koalas vaccinated 6 months prior. Each hypothesis was tested as a structural equation model separately for either the urogenital or the ocular site to evaluate possible causality among measured variables. Model averaging was used as multiple models fit the data, and the strength of relationships was examined through averaged coefficients and the raw data. Results: We found more relationships in urogenital models as compared to ocular models, particularly those with interleukin 17 (IL17) mRNA expression compared to models with interferon gamma (IFNγ) expression. In the averaged model with IL17, urogenital chlamydial load was positively associated with disease and negatively associated with IL17 expression. MOMP vaccination had a trending effect for reducing urogenital chlamydial load and also had a strong effect on increasing IL17 expression. Not surprisingly, urogenital chlamydial load was a positive predictor for the development of urogenital disease at 6 months post-vaccination. Conclusions: Despite multiple potential sources of variation owing to the koalas in this study being free-ranging, our analyses provide unique insights into the effects of vaccinating against Chlamydia. Using structural equation modeling, this study has helped illuminate that the expression of the immune cytokine IL17 is linked to MOMP vaccination, and animals with a high urogenital chlamydial load expressed less IL17 and were more likely to develop disease, enhancing previous investigations. Going beyond univariate statistics, the methods used in this study can be applied to other preclinical vaccination experiments to identify important direct and indirect factors underpinning the effects of a vaccine.
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Affiliation(s)
- David Lizárraga
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia.,Genecology Research Centre, School of Science and Engineering, University of Sunshine Coast, Sippy Downs, QLD, Australia
| | - Peter Timms
- Genecology Research Centre, School of Science and Engineering, University of Sunshine Coast, Sippy Downs, QLD, Australia
| | - Bonnie L Quigley
- Genecology Research Centre, School of Science and Engineering, University of Sunshine Coast, Sippy Downs, QLD, Australia
| | - Jon Hanger
- Endeavour Veterinary Ecology Pty Ltd., Toorbul, QLD, Australia
| | - Scott Carver
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
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5
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Robbins A, Hanger J, Jelocnik M, Quigley BL, Timms P. Koala immunogenetics and chlamydial strain type are more directly involved in chlamydial disease progression in koalas from two south east Queensland koala populations than koala retrovirus subtypes. Sci Rep 2020; 10:15013. [PMID: 32929174 PMCID: PMC7490398 DOI: 10.1038/s41598-020-72050-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 08/18/2020] [Indexed: 02/02/2023] Open
Abstract
Chlamydial disease control is increasingly utilised as a management tool to stabilise declining koala populations, and yet we have a limited understanding of the factors that contribute to disease progression. To examine the impact of host and pathogen genetics, we selected two geographically separated south east Queensland koala populations, differentially affected by chlamydial disease, and analysed koala major histocompatibility complex (MHC) genes, circulating strains of Chlamydia pecorum and koala retrovirus (KoRV) subtypes in longitudinally sampled, well-defined clinical groups. We found that koala immunogenetics and chlamydial genotypes differed between the populations. Disease progression was associated with specific MHC alleles, and we identified two putative susceptibility (DCb 03, DBb 04) and protective (DAb 10, UC 01:01) variants. Chlamydial genotypes belonging to both Multi-Locus Sequence Typing sequence type (ST) 69 and ompA genotype F were associated with disease progression, whereas ST 281 was associated with the absence of disease. We also detected different ompA genotypes, but not different STs, when long-term infections were monitored over time. By comparison, KoRV profiles were not significantly associated with disease progression. These findings suggest that chlamydial genotypes vary in pathogenicity and that koala immunogenetics and chlamydial strains are more directly involved in disease progression than KoRV subtypes.
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Affiliation(s)
- Amy Robbins
- Genecology Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, QLD, 4556, Australia.,Endeavour Veterinary Ecology Pty Ltd, 1695 Pumicestone Road, Toorbul, QLD, 4510, Australia
| | - Jonathan Hanger
- Endeavour Veterinary Ecology Pty Ltd, 1695 Pumicestone Road, Toorbul, QLD, 4510, Australia
| | - Martina Jelocnik
- Genecology Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, QLD, 4556, Australia
| | - Bonnie L Quigley
- Genecology Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, QLD, 4556, Australia
| | - Peter Timms
- Genecology Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, QLD, 4556, Australia.
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6
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Quigley BL, Timms P. Helping koalas battle disease - Recent advances in Chlamydia and koala retrovirus (KoRV) disease understanding and treatment in koalas. FEMS Microbiol Rev 2020; 44:583-605. [PMID: 32556174 PMCID: PMC8600735 DOI: 10.1093/femsre/fuaa024] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/14/2020] [Indexed: 12/31/2022] Open
Abstract
The iconic Australian marsupial, the koala (Phascolarctos cinereus), has suffered dramatic population declines as a result of habitat loss and fragmentation, disease, vehicle collision mortality, dog attacks, bushfires and climate change. In 2012, koalas were officially declared vulnerable by the Australian government and listed as a threatened species. In response, research into diseases affecting koalas has expanded rapidly. The two major pathogens affecting koalas are Chlamydia pecorum, leading to chlamydial disease and koala retrovirus (KoRV). In the last eight years, these pathogens and their diseases have received focused study regarding their sources, genetics, prevalence, disease presentation and transmission. This has led to vast improvements in pathogen detection and treatment, including the ongoing development of vaccines for each as a management and control strategy. This review will summarize and highlight the important advances made in understanding and combating C. pecorum and KoRV in koalas, since they were declared a threatened species. With complementary advances having also been made from the koala genome sequence and in our understanding of the koala immune system, we are primed to make a significant positive impact on koala health into the future.
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Affiliation(s)
- Bonnie L Quigley
- Genecology Research Centre, University of the Sunshine Coast,
90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
| | - Peter Timms
- Genecology Research Centre, University of the Sunshine Coast,
90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
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7
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Fabijan J, Sarker N, Speight N, Owen H, Meers J, Simmons G, Seddon J, Emes RD, Tarlinton R, Hemmatzadeh F, Woolford L, Trott DJ. Pathological Findings in Koala Retrovirus-positive Koalas (Phascolarctos cinereus) from Northern and Southern Australia. J Comp Pathol 2020; 176:50-66. [PMID: 32359636 DOI: 10.1016/j.jcpa.2020.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/29/2020] [Accepted: 02/06/2020] [Indexed: 01/05/2023]
Abstract
Koala retrovirus (KoRV) infection shows differences in prevalence and load between northern and southern Australian koala populations; however, the effect of this on diseases such as lymphoma and chlamydial disease is unclear. This study compared clinicopathological findings, haematology and splenic lymphoid area of KoRV-positive koalas from northern (Queensland [Qld], n = 67) and southern (South Australia [SA], n = 92) populations in order to provide further insight into KoRV pathogenesis. Blood was collected for routine haematology and for measurement of KoRV proviral load by quantitative polymerase chain reaction (qPCR). Plasma samples were assessed for KoRV viral load by reverse transcriptase qPCR and conjunctival and cloacal swabs were collected for measurement of the load of Chlamydia pecorum (qPCR). During necropsy examination, spleen was collected for lymphoid area analysis. Lymphoma was morphologically similar between the populations and occurred in koalas with the highest KoRV proviral and viral loads. Severe ocular chlamydial disease was observed in both populations, but urinary tract disease was more severe in Qld, despite similar C. pecorum loads. No associations between KoRV and chlamydial disease severity or load were observed, except in SA where viral load correlated positively with chlamydial disease severity. In both populations, proviral and viral loads correlated positively with lymphocyte and metarubricyte counts and correlated negatively with erythrocyte and neutrophil counts. Splenic lymphoid area was correlated positively with viral load. This study has shown further evidence for KoRV-induced oncogenesis and highlighted that lymphocytes and splenic lymphoid tissue may be key sites for KoRV replication. However, KoRV infection appears to be highly complex and continued investigation is required to fully understand its pathogenesis.
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Affiliation(s)
- J Fabijan
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia.
| | - N Sarker
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - N Speight
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - H Owen
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - J Meers
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - G Simmons
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - J Seddon
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - R D Emes
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire, UK
| | - R Tarlinton
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire, UK
| | - F Hemmatzadeh
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - L Woolford
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - D J Trott
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
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8
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Waugh CA, Timms P. A proposed roadmap for the control of infections in wildlife using Chlamydia vaccine development in koalas Phascolarctos cinereus as a template. WILDLIFE BIOLOGY 2020. [DOI: 10.2981/wlb.00627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Courtney A. Waugh
- C. Waugh ✉ , Faculty of Bioscience and Aquaculture, Nord Univ., Steinkjer, Norway
| | - Peter Timms
- P. Timms, Univ. of the Sunshine Coast, Sippy Downs, Queensland, Australia
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9
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EPIDEMIOLOGY OF CHLAMYDIA-INDUCED REPRODUCTIVE DISEASE IN MALE KOALAS (PHASCOLARCTOS CINEREUS) FROM SOUTHEAST QUEENSLAND, AUSTRALIA AS ASSESSED FROM PENILE URETHRAL SWABS AND SEMEN. J Wildl Dis 2020. [DOI: 10.7589/2019-03-062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Longitudinal study of wild koalas (Phascolarctos cinereus) reveals chlamydial disease progression in two thirds of infected animals. Sci Rep 2019; 9:13194. [PMID: 31519969 PMCID: PMC6744427 DOI: 10.1038/s41598-019-49382-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 08/23/2019] [Indexed: 01/12/2023] Open
Abstract
Chlamydial disease threatens many of Australia’s koala populations, and yet our understanding of chlamydial epidemiology and disease dynamics in koalas is limited by a lack of comprehensive, longitudinal population studies. To address this, we utilised longitudinal samples from a large-scale population study of wild koalas in south-east Queensland, to follow chlamydial infections over time and to investigate some of the drivers of disease progression. Our findings show, firstly, that almost two thirds of chlamydial infections progressed to disease, challenging the notion that chlamydial infections in koalas commonly remain chronic and asymptomatic. Secondly, disease progression at the urogenital tract site was associated with infection load, and urogenital tract shedding was significantly higher when koalas acquired a new infection. Thirdly, chronic chlamydial exposure was not necessary for pathogenic sequelae to develop, such as infertility and mortality. Fourthly, ompA-characterised strain sub-types may reflect tissue tropisms and pathogenicity, and the chlamydial status of some chronically infected koalas may be explained by reinfections with novel genotypes. Finally, successful antimicrobial treatment provided only short-term protection against reinfection and disease progression in susceptible koalas. These findings highlight the importance of identifying and preventing chlamydial infections in koalas, informing new population management strategies and research priorities.
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11
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Changes in Endogenous and Exogenous Koala Retrovirus Subtype Expression over Time Reflect Koala Health Outcomes. J Virol 2019; 93:JVI.00849-19. [PMID: 31243137 DOI: 10.1128/jvi.00849-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 06/13/2019] [Indexed: 01/23/2023] Open
Abstract
Koala retrovirus (KoRV) is unique in that it exists as both an exogenous and actively endogenizing gamma retrovirus of koalas. While nine subtypes of KoRV have been recognized, focused study of these subtypes in koalas over time and with different health outcomes has been lacking. Therefore, in this study, three wild koala cohorts were established and monitored to examine KoRV proviral and expression data from koalas that either remained healthy over time, began healthy before developing chlamydial cystitis, or presented with chlamydial cystitis and were treated with antibiotics. Deep sequencing of the proviral KoRV envelope gene revealed KoRV-A, -B, -D, and -F to be the major subtypes in this population and allowed for subtype-specific assays to be created. Quantification of KoRV transcripts revealed that KoRV-D expression mirrored the total KoRV expression levels (106 copies/ml of plasma), with KoRV-A and KoRV-F expression being ∼10-fold less and KoRV-B expression being ∼100-fold less, when detected. Strikingly, there was significantly higher expression of KoRV-D in healthy koalas than in koalas that developed chlamydial cystitis, with healthy koalas expressing a major KoRV-D/minor KoRV-A profile, whereas koalas that developed cystitis had variable KoRV expression profiles. Total anti-KoRV IgG antibody levels were found not to correlate with the expression of total KoRV or any individual KoRV subtype. Finally, KoRV expression was consistent between systemic and mucosal body sites and during antibiotic treatment. Collectively, this gives a comprehensive picture of KoRV dynamics during several important koala health states.IMPORTANCE The long-term survival of the koala is under serious threat, with this iconic marsupial being declared "vulnerable" by the Australian Government and officially listed as a threatened species. KoRV is clearly contributing to the overall health status of koalas, and research into this virus has been lacking detailed study of the multiple subtypes at both the proviral and expressed viral levels over time. By designing new subtype-specific assays and following well-defined koala cohorts over time, this study has generated a new more complete picture of KoRV and its relationship to koala health outcomes in the wild. Only by building a comprehensive picture of KoRV during both koala health and disease can we bring meaningful koala health interventions into better focus.
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12
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Hulse LS, McDonald S, Johnston SD, Beagley KW. Rapid point-of-care diagnostics for the detection of Chlamydia pecorum in koalas (Phascolarctos cinereus) using loop-mediated isothermal amplification without nucleic acid purification. Microbiologyopen 2019; 8:e916. [PMID: 31419041 PMCID: PMC6925175 DOI: 10.1002/mbo3.916] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 12/21/2022] Open
Abstract
Infectious disease, predominately chlamydiosis, contributes significantly to the decline in health of wild koala (Phascolarctos cinereus) populations in some regions of Australia. In this study, we describe the development and evaluation of a simple, sensitive, and specific loop‐mediated isothermal amplification (LAMP) assay for the detection of Chlamydia pecorum in koalas as a point‐of‐care diagnostic tool that can be used in any wildlife hospital and in the field on specialized instrumentation. A set of primers targeting a 188‐bp region of the C. pecorum genome was designed. 100% specificity of the LAMP assay was revealed by demonstrating no cross‐reactivity with 33 nontarget pathogens, and complete correlation with qPCR results for 43 clinical swabs collected opportunistically from wildlife hospitals. In sensitivity evaluations, the technique successfully detected serial dilutions of extracted C. pecorum DNA with a detection limit of 44 IFU/ml.
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Affiliation(s)
- Lyndal S Hulse
- School of Agriculture and Food Sciences, University of Queensland, Gatton, QLD, Australia
| | | | - Stephen D Johnston
- School of Agriculture and Food Sciences, University of Queensland, Gatton, QLD, Australia
| | - Kenneth W Beagley
- Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
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13
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Fabijan J, Miller D, Olagoke O, Woolford L, Boardman W, Timms P, Polkinghorne A, Simmons G, Hemmatzadeh F, Trott DJ, Speight KN. Prevalence and clinical significance of koala retrovirus in two South Australian koala (Phascolarctos cinereus) populations. J Med Microbiol 2019; 68:1072-1080. [PMID: 31162024 DOI: 10.1099/jmm.0.001009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PURPOSE Koala retrovirus (KoRV-A) is 100 % prevalent in northern Australian (Queensland and New South Wales) koala populations, where KoRV-B has been associated with Chlamydia pecorum disease and the development of lymphosarcoma. In southern populations (Victoria and South Australia), KoRV-A is less prevalent and KoRV-B has not been detected in Victoria, while the current prevalence in South Australian populations is unknown but is thought to be low. This study aimed to determine (i) the prevalence of KoRV in the two largest South Australian koala populations [Kangaroo Island (KI) and Mount Lofty Ranges (MLR)], (ii) KoRV subtype and (iii) if an association between KoRV and C. pecorum exists. METHODOLOGY Wild koalas were sampled in KI ( n =170) between 2014 and 2017 and in MLR ( n =75) in 2016. Clinical examinations were performed, with blood collected for KoRV detection and typing by PCR. RESULTS KoRV prevalence was 42.4 % [72/170, 95 % confidence interval (CI): 34.9-49.8 %] in KI and 65.3 % (49/75, 95 % CI: 54.6-76.1 %) in MLR. Only KoRV-A, and not KoRV-B, was detected in both populations. In MLR, there was no statistical association between KoRV and C. pecorum infection (P =0.740), or KoRV and C. pecorum disease status ( P=0.274), although KoRV-infected koalas were more likely to present with overt C. pecorum disease than subclinical infection (odds ratio: 3.15, 95 % CI: 0.91-5.39). CONCLUSION KoRV-A is a prevalent pathogen in wild South Australian koala populations. Future studies should continue to investigate KoRV and C. pecorum associations, as the relationship is likely to be complex and to differ between the northern and southern populations.
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Affiliation(s)
- Jessica Fabijan
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Darren Miller
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Olusola Olagoke
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Lucy Woolford
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Wayne Boardman
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Peter Timms
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Adam Polkinghorne
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Greg Simmons
- School of Veterinary Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - Farhid Hemmatzadeh
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Darren J Trott
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - K Natasha Speight
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
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14
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Chlamydiaceae: Diseases in Primary Hosts and Zoonosis. Microorganisms 2019; 7:microorganisms7050146. [PMID: 31137741 PMCID: PMC6560403 DOI: 10.3390/microorganisms7050146] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 05/19/2019] [Accepted: 05/20/2019] [Indexed: 12/23/2022] Open
Abstract
Bacteria of the Chlamydiaceae family are a type of Gram-negative microorganism typified by their obligate intracellular lifestyle. The majority of the members in the Chlamydiaceae family are known pathogenic organisms that primarily infect the host mucosal surfaces in both humans and animals. For instance, Chlamydia trachomatis is a well-known etiological agent for ocular and genital sexually transmitted diseases, while C. pneumoniae has been implicated in community-acquired pneumonia in humans. Other chlamydial species such as C. abortus, C. caviae, C. felis, C. muridarum, C. pecorum, and C. psittaci are important pathogens that are associated with high morbidities in animals. Importantly, some of these animal pathogens have been recognized as zoonotic agents that pose a significant infectious threat to human health through cross-over transmission. The current review provides a succinct recapitulation of the characteristics as well as transmission for the previously established members of the Chlamydiaceae family and a number of other recently described chlamydial organisms.
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15
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Cristescu RH, Miller RL, Schultz AJ, Hulse L, Jaccoud D, Johnston S, Hanger J, Booth R, Frère CH. Developing noninvasive methodologies to assess koala population health through detecting Chlamydia from scats. Mol Ecol Resour 2019; 19:957-969. [PMID: 30681773 DOI: 10.1111/1755-0998.12999] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 11/13/2018] [Accepted: 01/14/2019] [Indexed: 01/17/2023]
Abstract
Wildlife diseases are a recognized driver of global biodiversity loss, have substantial economic impacts, and are increasingly becoming a threat to human health. Disease surveillance is critical but remains difficult in the wild due to the substantial costs and potential biases associated with most disease detection methods. Noninvasive scat surveys have been proposed as a health monitoring methodology to overcome some of these limitations. Here, we use the known threat of Chlamydia disease to the iconic, yet vulnerable, koala Phascolarctos cinereus to compare three methods for Chlamydia detection in scats: multiplex quantitative PCR, next generation sequencing, and a detection dog specifically trained on scats from Chlamydia-infected koalas. All three methods demonstrated 100% specificity, while sensitivity was variable. Of particular interest is the variable sensitivity of these diagnostic tests to detect sick individuals (i.e., not only infection as confirmed by Chlamydia-positive swabs, but with observable clinical signs of the disease); for koalas with urogenital tract disease signs, sensitivity was 78% with quantitative PCR, 50% with next generation genotyping and 100% with the detection dog method. This may be due to molecular methods having to rely on high-quality DNA whereas the dog most likely detects volatile organic compounds. The most appropriate diagnostic test will vary with disease prevalence and the specific aims of disease surveillance. Acknowledging that detection dogs might not be easily accessible to all, the future development of affordable and portable "artificial noses" to detect diseases from scats in the field might enable cost-effective, rapid and large-scale disease surveillance.
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Affiliation(s)
- Romane H Cristescu
- Global Change Ecology Research Group, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Russell L Miller
- Global Change Ecology Research Group, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Anthony J Schultz
- Global Change Ecology Research Group, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Lyndal Hulse
- School of Agriculture and Food Sciences, University of Queensland, Gatton, Queensland, Australia
| | - Damian Jaccoud
- Diversity Arrays Technology, University of Canberra, Bruce, Australian Capital Territory, Australia
| | - Stephen Johnston
- School of Agriculture and Food Sciences, University of Queensland, Gatton, Queensland, Australia
| | - Jon Hanger
- Endeavour Veterinary Ecology, Toorbul, Queensland, Australia
| | - Rosie Booth
- Australia Zoo Wildlife Hospital, Beerwah, Queensland, Australia
| | - Céline H Frère
- Global Change Ecology Research Group, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
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16
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Fabijan J, Caraguel C, Jelocnik M, Polkinghorne A, Boardman WSJ, Nishimoto E, Johnsson G, Molsher R, Woolford L, Timms P, Simmons G, Hemmatzadeh F, Trott DJ, Speight N. Chlamydia pecorum prevalence in South Australian koala (Phascolarctos cinereus) populations: Identification and modelling of a population free from infection. Sci Rep 2019; 9:6261. [PMID: 31000763 PMCID: PMC6472425 DOI: 10.1038/s41598-019-42702-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 04/02/2019] [Indexed: 11/21/2022] Open
Abstract
Chlamydia pecorum is an established and prevalent infection that produces severe clinical disease in many koala populations, contributing to dramatic population declines. In wild South Australian koala populations, C. pecorum occurrence and distribution is unknown. Here, C. pecorum-specific real-time quantitative PCR (qPCR) was applied to ocular and urogenital swabs from targeted surveys of wild koalas from the mainland Mount Lofty Ranges (MLR) (n = 75) and Kangaroo Island (KI) (n = 170) populations. Historical data from 13,081 KI koalas (1997–2018) provided additional evidence for assessing the absence of C. pecorum infection. In the MLR population, 46.7% (CI: 35.1–58.6%) of koalas were C. pecorum positive by qPCR but only 4% had grade 3 clinical disease. MLR koala fertility was significantly reduced by C. pecorum infection; all reproductively active females (n = 16) were C. pecorum negative, whereas 85.2% of inactive females (n = 23) were positive (P < 0.001). KI koalas were C. pecorum negative and the population was demonstrated to be free of C. pecorum infection with 95% confidence. C. pecorum is a real threat for the sustainability of the koala and KI is possibly the last isolated, large C. pecorum-free population remaining in Australia. These koalas could provide a safeguard against this serious disease threat to an iconic Australian species.
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Affiliation(s)
- Jessica Fabijan
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia.
| | - Charles Caraguel
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Martina Jelocnik
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, 4558, Queensland, Australia
| | - Adam Polkinghorne
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, 4558, Queensland, Australia
| | - Wayne S J Boardman
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Elisa Nishimoto
- Kangaroo Island Veterinary Clinic, Kingscote, 5223, South Australia, Australia
| | - Greg Johnsson
- Kangaroo Island Veterinary Clinic, Kingscote, 5223, South Australia, Australia
| | - Robyn Molsher
- Department for Environment and Water, Adelaide, 5000, South Australia, Australia
| | - Lucy Woolford
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, 4558, Queensland, Australia
| | - Greg Simmons
- School of Veterinary Sciences, The University of Queensland, Gatton, 4343, Queensland, Australia
| | - Farhid Hemmatzadeh
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Darren J Trott
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
| | - Natasha Speight
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, South Australia, Australia
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17
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Harvey E, Madden D, Polkinghorne A, Holmes EC. Identification of A Novel Picorna-Like Virus, Burpengary Virus, that is Negatively Associated with Chlamydial Disease in the Koala. Viruses 2019; 11:E211. [PMID: 30832350 PMCID: PMC6466430 DOI: 10.3390/v11030211] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 02/05/2023] Open
Abstract
Koalas (Phascolarctos cinereus) are native Australian marsupials whose populations are in decline from a range of threats. Infectious diseases caused by the bacterium Chlamydia pecorum and other pathogens are of particular concern. We analysed 26 poly-A selected RNA-sequencing libraries from a data set designed to study the immune response of koalas to ocular chlamydial infection. Using virus discovery techniques, we identified the coding-complete genome sequence of a novel picorna-like virus, denoted Burpengary virus, that was most common in south-east Queensland. Notably, abundance measurements of the virus across all 26 libraries revealed an inverse relationship between abundance and ocular disease in koalas, suggesting that the co-infection of Burpengary virus and Chlamydia pecorum is inhibited.
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Affiliation(s)
- Erin Harvey
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Danielle Madden
- Animal Research Centre, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia.
| | - Adam Polkinghorne
- Animal Research Centre, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia.
| | - Edward C Holmes
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
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18
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Fernandez CM, Schmertmann LJ, Higgins DP, Casteriano A, Irinyi L, Mella VSA, Crowther MS, Meyer W, Krockenberger MB. Genetic differences in Chlamydia pecorum between neighbouring sub-populations of koalas (Phascolarctos cinereus). Vet Microbiol 2019; 231:264-270. [PMID: 30853132 DOI: 10.1016/j.vetmic.2019.02.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/04/2019] [Accepted: 02/11/2019] [Indexed: 01/09/2023]
Abstract
Chlamydiosis, caused by Chlamydia pecorum, is regarded as an important threat to koala populations. Across the koala's geographical range, disease severity associated with C. pecorum infection varies, with pathogen diversity and strain pathogenicity being likely important factors. To examine C. pecorum diversity on a sub-population level a Multi-Locus Sequence Typing (MLST) scheme, containing the housekeeping genes; gatA, oppA_3, hflX, gidA, enoA, hemN and fumC, was used to type strains from two sub-populations of koalas from the Liverpool Plains, NSW, Australia, with different disease expressions. Typing of samples from 2015 to 2017, revealed a significant association between sequence type ST 69 and clinical disease and a significant difference in sequence type frequencies between sub-populations. Sequence type ST 69 has previously been identified in both subclinical and clinically diseased koalas indicating that these markers alone are not illustrative of pathogenicity. However, recent emergence of this sequence type in a naïve population may explain the differing disease expressions. Sequence types ST 73 and ST 69 have been described in koalas across a broad geographic range, indicating multiple introduction events and/or a limited veracity of the MLST loci to explore fine scale epidemiological investigations, particularly those examining the interface between pathogenic strain and disease outcome.
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Affiliation(s)
- Cristina M Fernandez
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Hospital, Faculty of Medicine and Health, Westmead Clinical School, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia; The Westmead Institute for Medical Research, 176 Hawkesbury Road, 2145, Westmead, NSW, Australia; Sydney School of Veterinary Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Laura J Schmertmann
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Hospital, Faculty of Medicine and Health, Westmead Clinical School, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia; The Westmead Institute for Medical Research, 176 Hawkesbury Road, 2145, Westmead, NSW, Australia; Sydney School of Veterinary Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Damien P Higgins
- Sydney School of Veterinary Science, The University of Sydney, Sydney, 2006, NSW, Australia; Marie Bashir Institute for Emerging Infectious diseases and Biosecurity, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia
| | - Andrea Casteriano
- Sydney School of Veterinary Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Laszlo Irinyi
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Hospital, Faculty of Medicine and Health, Westmead Clinical School, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia; The Westmead Institute for Medical Research, 176 Hawkesbury Road, 2145, Westmead, NSW, Australia
| | - Valentina S A Mella
- School of Life and Environmental Sciences, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Mathew S Crowther
- School of Life and Environmental Sciences, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Wieland Meyer
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Hospital, Faculty of Medicine and Health, Westmead Clinical School, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia; The Westmead Institute for Medical Research, 176 Hawkesbury Road, 2145, Westmead, NSW, Australia; Marie Bashir Institute for Emerging Infectious diseases and Biosecurity, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia
| | - Mark B Krockenberger
- Sydney School of Veterinary Science, The University of Sydney, Sydney, 2006, NSW, Australia; Marie Bashir Institute for Emerging Infectious diseases and Biosecurity, The University of Sydney, 176 Hawkesbury road, 2145, Westmead, NSW, Australia.
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19
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Nyari S, Booth R, Quigley BL, Waugh CA, Timms P. Therapeutic effect of a Chlamydia pecorum recombinant major outer membrane protein vaccine on ocular disease in koalas (Phascolarctos cinereus). PLoS One 2019; 14:e0210245. [PMID: 30615687 PMCID: PMC6322743 DOI: 10.1371/journal.pone.0210245] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 12/19/2018] [Indexed: 12/29/2022] Open
Abstract
Chlamydia pecorum is responsible for causing ocular infection and disease which can lead to blindness in koalas (Phascolarctos cinereus). Antibiotics are the current treatment for chlamydial infection and disease in koalas, however, they can be detrimental for the koala’s gastrointestinal tract microbiota and in severe cases, can lead to dysbiosis and death. In this study, we evaluated the therapeutic effects provided by a recombinant chlamydial major outer membrane protein (MOMP) vaccine on ocular disease in koalas. Koalas with ocular disease (unilateral or bilateral) were vaccinated and assessed for six weeks, evaluating any changes to the conjunctival tissue and discharge. Samples were collected pre- and post-vaccination to evaluate both humoral and cell-mediated immune responses. We further assessed the infecting C. pecorum genotype, host MHC class II alleles and presence of koala retrovirus type (KoRV-B). Our results clearly showed an improvement in the clinical ocular disease state of all seven koalas, post-vaccination. We observed increases in ocular mucosal IgA antibodies to whole C. pecorum elementary bodies, post-vaccination. We found that systemic cell-mediated immune responses to interferon-γ, interleukin-6 and interleukin-17A were not significantly predictive of ocular disease in koalas. Interestingly, one koala did not have as positive a clinical response (in one eye primarily) and this koala was infected with a C. pecorum genotype (E’) that was not used as part of the vaccine formula (MOMP genotypes A, F and G). The predominant MHC class II alleles identified were DAb*19, DAb*21 and DBb*05, with no two koalas identified with the same genetic sequence. Additionally, KoRV-B, which is associated with chlamydial disease outcome, was identified in two (29%) ocular diseased koalas, which still produced vaccine-induced immune responses and clinical ocular improvements post-vaccination. Our findings show promise for the use of a recombinant chlamydial MOMP vaccine for the therapeutic treatment of ocular disease in koalas.
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Affiliation(s)
- Sharon Nyari
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Rosemary Booth
- Australia Zoo Wildlife Hospital, Beerwah, Queensland, Australia
| | - Bonnie L. Quigley
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Courtney A. Waugh
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Peter Timms
- University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- * E-mail:
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20
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Hulse LS, Hickey D, Mitchell JM, Beagley KW, Ellis W, Johnston SD. Development and application of two multiplex real-time PCR assays for detection and speciation of bacterial pathogens in the koala. J Vet Diagn Invest 2018; 30:523-529. [PMID: 29629645 PMCID: PMC6505923 DOI: 10.1177/1040638718770490] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Infectious diseases have contributed to the decline in the health of koala ( Phascolarctos cinereus) populations in the wild in some regions of Australia. Herein we report the development and validation of 2 multiplex real-time PCR (rtPCR) panels for the simultaneous detection of Mycoplasma spp., Ureaplasma spp., Bordetella bronchiseptica, and Chlamydia, including speciation and quantification of Chlamydia, in ocular, reproductive, and nasal swab samples in addition to semen and male urogenital and reproductive tissues, from koalas. Each rtPCR panel was developed for use as a single-tube reaction using pathogen-specific primers and fluorescently labeled probe sets. DNA extracted from reference strains and isolates was used for validation of sequence gene targets for the multiplex rtPCR panels. Each panel was shown to be sensitive and specific in detecting and differentiating the bacterial pathogens. The multiplex rtPCR panels were used to screen clinical samples from free-ranging and hospitalized koalas for multiple pathogens simultaneously. The multiplex rtPCR will improve turnaround time compared to individual-pathogen rtPCR methods used, to date, for confirmation of diagnosis and will provide the wildlife clinician with the ability to make treatment decisions more rapidly.
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Affiliation(s)
- Lyndal S. Hulse
- Lyndal S. Hulse, Wildlife
Biology Unit, School of Agriculture and Food Science, University of Queensland,
Gatton 4343, QLD, Australia.
| | - Danica Hickey
- School of Agriculture and Food Sciences, University
of Queensland, Gatton, Queensland, Australia (Hulse, Mitchell, Ellis,
Johnston)
- Institute of Health and Biomedical Innovation
(Hickey, Beagley), Faculty of Health, Queensland University of Technology,
Brisbane, Queensland, Australia
- School of Biomedical Sciences (Hickey, Beagley),
Faculty of Health, Queensland University of Technology, Brisbane, Queensland,
Australia
| | - Jessica M. Mitchell
- School of Agriculture and Food Sciences, University
of Queensland, Gatton, Queensland, Australia (Hulse, Mitchell, Ellis,
Johnston)
- Institute of Health and Biomedical Innovation
(Hickey, Beagley), Faculty of Health, Queensland University of Technology,
Brisbane, Queensland, Australia
- School of Biomedical Sciences (Hickey, Beagley),
Faculty of Health, Queensland University of Technology, Brisbane, Queensland,
Australia
| | - Kenneth W. Beagley
- School of Agriculture and Food Sciences, University
of Queensland, Gatton, Queensland, Australia (Hulse, Mitchell, Ellis,
Johnston)
- Institute of Health and Biomedical Innovation
(Hickey, Beagley), Faculty of Health, Queensland University of Technology,
Brisbane, Queensland, Australia
- School of Biomedical Sciences (Hickey, Beagley),
Faculty of Health, Queensland University of Technology, Brisbane, Queensland,
Australia
| | - William Ellis
- School of Agriculture and Food Sciences, University
of Queensland, Gatton, Queensland, Australia (Hulse, Mitchell, Ellis,
Johnston)
- Institute of Health and Biomedical Innovation
(Hickey, Beagley), Faculty of Health, Queensland University of Technology,
Brisbane, Queensland, Australia
- School of Biomedical Sciences (Hickey, Beagley),
Faculty of Health, Queensland University of Technology, Brisbane, Queensland,
Australia
| | - Stephen D. Johnston
- School of Agriculture and Food Sciences, University
of Queensland, Gatton, Queensland, Australia (Hulse, Mitchell, Ellis,
Johnston)
- Institute of Health and Biomedical Innovation
(Hickey, Beagley), Faculty of Health, Queensland University of Technology,
Brisbane, Queensland, Australia
- School of Biomedical Sciences (Hickey, Beagley),
Faculty of Health, Queensland University of Technology, Brisbane, Queensland,
Australia
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21
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Nyari S, Khan SA, Rawlinson G, Waugh CA, Potter A, Gerdts V, Timms P. Vaccination of koalas (Phascolarctos cinereus) against Chlamydia pecorum using synthetic peptides derived from the major outer membrane protein. PLoS One 2018; 13:e0200112. [PMID: 29953523 PMCID: PMC6023247 DOI: 10.1371/journal.pone.0200112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/18/2018] [Indexed: 11/18/2022] Open
Abstract
Chlamydia pecorum is a mucosal infection, which causes debilitating disease of the urinary tract, reproductive tract and ocular sites of koalas (Phascolarctos cinereus). While antibiotics are available for treatment, they are detrimental to the koalas' gastrointestinal tract microflora leaving the implementation of a vaccine as an ideal option for the long-term management of koala populations. We have previously reported on the successes of an anti-chlamydial recombinant major outer membrane protein (rMOMP) vaccine however, recombinant protein based vaccines are not ideal candidates for scale up from the research level to small-medium production level for wider usage. Peptide based vaccines are a promising area for vaccine development, because peptides are stable, cost effective and easily produced. In this current study, we assessed, for the first time, the immune responses to a synthetic peptide based anti-chlamydial vaccine in koalas. Five healthy male koalas were vaccinated with two synthetic peptides derived from C. pecorum MOMP and another five healthy male koalas were vaccinated with full length recombinant C. pecorum MOMP (genotype G). Systemic (IgG) and mucosal (IgA) antibodies were quantified and pre-vaccination levels compared to post-vaccination levels (12 and 26 weeks). MOMP-peptide vaccinated koalas produced Chlamydia-specific IgG and IgA antibodies, which were able to recognise not only the genotype used in the vaccination, but also MOMPs from several other koala C. pecorum genotypes. In addition, IgA antibodies induced at the ocular site not only recognised recombinant MOMP protein but also, whole native chlamydial elementary bodies. Interestingly, some MOMP-peptide vaccinated koalas showed a stronger and more sustained vaccine-induced mucosal IgA antibody response than observed in MOMP-protein vaccinated koalas. These results demonstrate that a synthetic MOMP peptide based vaccine is capable of inducing a Chlamydia-specific antibody response in koalas and is a promising candidate for future vaccine development.
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Affiliation(s)
- Sharon Nyari
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Shahneaz Ali Khan
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Galit Rawlinson
- Lone Pine Koala Sanctuary, Fig Tree Pocket, Queensland, Australia
| | - Courtney A. Waugh
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Andrew Potter
- Vaccine and Infectious Disease Organisation–International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Canada
| | - Volker Gerdts
- Vaccine and Infectious Disease Organisation–International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Canada
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- * E-mail:
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22
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Quigley BL, Carver S, Hanger J, Vidgen ME, Timms P. The relative contribution of causal factors in the transition from infection to clinical chlamydial disease. Sci Rep 2018; 8:8893. [PMID: 29891934 PMCID: PMC5995861 DOI: 10.1038/s41598-018-27253-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/25/2018] [Indexed: 12/21/2022] Open
Abstract
Chlamydia is a major bacterial pathogen in humans and animals globally. Yet 80% of infections never progress to clinical disease. Decades of research have generated an interconnected network linking pathogen, host, and environmental factors to disease expression, but the relative importance of these and whether they account for disease progression remains unknown. To address this, we used structural equation modeling to evaluate putative factors likely to contribute to urogenital and ocular chlamydial disease in the koala (Phascolarctos cinereus). These factors include Chlamydia detection, load, and ompA genotype; urogenital and ocular microbiomes; host sex, age, weight, body condition; breading season, time of year; location; retrovirus co-infection; and major histocompatibility complex class II (MHCII) alleles. We show different microbiological processes underpin disease progression at urogenital and ocular sites. From each category of factors, urogenital disease was most strongly predicted by chlamydial PCR detection and load, koala body condition and environmental location. In contrast, ocular disease was most strongly predicted by phylum-level Chlamydiae microbiome proportions, sampling during breeding season and co-infection with koala retrovirus subtype B. Host MHCII alleles also contributed predictive power to both disease models. Our results also show considerable uncertainty remains, suggesting major causal mechanisms are yet to be discovered.
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Affiliation(s)
- Bonnie L Quigley
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
| | - Scott Carver
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Jon Hanger
- Endeavour Veterinary Ecology, 1695 Pumicestone Road, Toorbul, Queensland, 4510, Australia
| | - Miranda E Vidgen
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia.
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Madden D, Whaite A, Jones E, Belov K, Timms P, Polkinghorne A. Koala immunology and infectious diseases: How much can the koala bear? DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 82:177-185. [PMID: 29382557 DOI: 10.1016/j.dci.2018.01.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 01/24/2018] [Accepted: 01/24/2018] [Indexed: 06/07/2023]
Abstract
Infectious diseases are contributing to the decline of the iconic Australian marsupial, the koala (Phascolarctos cinereus). Infections with the obligate intracellular bacteria, Chlamydia pecorum, cause debilitating ocular and urogenital-tract disease while the koala-retrovirus (KoRV) has been implicated in host immunosuppression and exacerbation of chlamydial pathogenesis. Although histological studies have provided insight into the basic architecture of koala immune tissues, our understanding of the koala immune response to infectious disease has been limited, until recently, by a lack of species-specific immune reagents. Recent advances in the characterisation of key immune genes have focused on advancing our understanding of the immune response to Chlamydia infection, revealing commonalities in disease pathologies and immunity between koalas and other hosts and paving the way for the development of a koala Chlamydia vaccine. This review summarises these recent findings and highlights key aspects of the koala immune system requiring further attention with particular regard to their most prominent infectious diseases.
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Affiliation(s)
- Danielle Madden
- Animal Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs 4556, Australia.
| | - Alessandra Whaite
- Animal Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs 4556, Australia.
| | - Elizabeth Jones
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, NSW 2006, Australia.
| | - Katherine Belov
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, NSW 2006, Australia.
| | - Peter Timms
- Animal Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs 4556, Australia.
| | - Adam Polkinghorne
- Animal Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs 4556, Australia.
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Chlamydia pecorum in Joint Tissue and Synovial Fluid of a Koala ( Phascolarctos cinereus) with Arthritis. J Wildl Dis 2018; 54:646-649. [PMID: 29498899 DOI: 10.7589/2017-10-248] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A small number of koalas ( Phascolarctos cinereus) presented to wildlife hospitals in Queensland, Australia, with signs of arthritis in one or more joints. Molecular analysis identified Chlamydia pecorum in the tarsal tissue and synovial fluid of an affected joint of a koala, suggesting that in addition to livestock, C. pecorum has the potential to cause arthritis in the koala.
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Borel N, Polkinghorne A, Pospischil A. A Review on Chlamydial Diseases in Animals: Still a Challenge for Pathologists? Vet Pathol 2018; 55:374-390. [PMID: 29310550 DOI: 10.1177/0300985817751218] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chlamydiae have a worldwide distribution causing a wide range of diseases in human hosts, livestock, and companion animals as well as in wildlife and exotic species. Moreover, they can persist in their hosts as asymptomatic infections for extended periods of time. The introduction of molecular techniques has revolutionized the Chlamydia field by expanding the host range of known chlamydial species but also by discovering new species and even new families of bacteria in the broader order Chlamydiales. The wide range of hosts, diseases, and tissues affected by chlamydiae complicate the diagnosis such that standard diagnostic approaches for these bacteria are rare. Bacteria of the Chlamydiales order are small and their inclusions are difficult to detect by standard microscopy. With the exception of avian and ovine chlamydiosis, macroscopic and/or histologic changes might not be pathognomic or indicative for a chlamydial infection or even not present at all. Moreover, detection of chlamydial DNA in specimens in the absence of other methods or related pathological lesions questions the significance of such findings. The pathogenic potential of the majority of recently identified Chlamydia-related bacteria remains largely unknown and awaits investigation through experimental or natural infection models including histomorphological characterization of associated lesions. This review aims to summarize the historical background and the most important developments in the field of animal chlamydial research in the past 5 years with a special focus on pathology. It will summarize the current nomenclature, present critical thoughts about diagnostics, and give an update on chlamydial infections in domesticated animals such as livestock, companion animals and birds, as well as free-ranging and captive wild animals such as reptiles, fish, and marsupials.
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Affiliation(s)
- Nicole Borel
- 1 Department of Pathobiology, Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Adam Polkinghorne
- 2 Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Australia
| | - Andreas Pospischil
- 1 Department of Pathobiology, Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
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Nyari S, Waugh CA, Dong J, Quigley BL, Hanger J, Loader J, Polkinghorne A, Timms P. Epidemiology of chlamydial infection and disease in a free-ranging koala (Phascolarctos cinereus) population. PLoS One 2017; 12:e0190114. [PMID: 29281731 PMCID: PMC5744985 DOI: 10.1371/journal.pone.0190114] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 12/10/2017] [Indexed: 12/01/2022] Open
Abstract
Chlamydial disease continues to be one of the main factors threatening the long-term survival of the koala (Phascolarctos cinereus). Despite this, large epidemiological studies of chlamydial infection and disease in wild koala populations are lacking. A better understanding of the prevalence, transmission and pathogenesis is needed to improve control measures, such as the development of vaccines. We investigated the prevalence of Chlamydia pecorum infection and disease in 160 koalas in a peri-urban wild population in Queensland, Australia and found that 31% of koalas were Chlamydia PCR positive and 28% had clinically detectable chlamydial disease. Most infections were at the urogenital site (27%; both males and females) with only 14% at the ocular site. Interestingly, we found that 27% (4/15) of koalas considered to be sexually immature (9–13 months) were already infected with C. pecorum, suggesting that a significant percentage of animals are infected directly from their mother. Ocular infection levels were less prevalent with increasing age (8% in koalas older than 4 years), whereas the prevalence of urogenital tract infections remained high into older age (26% in koalas older than 4 years), suggesting that, after mother-to-young transmission, C. pecorum is predominantly a sexually transmitted infection. While 28% of koalas in this population had clinically detectable chlamydial disease (primarily urogenital tract disease), many PCR positive koalas had no detectable disease and importantly, not all diseased animals were PCR positive. We also observed higher chlamydial loads in koalas who were C. pecorum infected without clinical disease than in koalas who were C. pecorum infected with clinical disease. These results shed light on the potential mechanisms of transmission of C. pecorum in koalas and also guide future control measures, such as vaccination.
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Affiliation(s)
- Sharon Nyari
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Courtney A. Waugh
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Jianbao Dong
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Bonnie L. Quigley
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Jonathan Hanger
- Endeavour Veterinary Ecology, Toorbul, Queensland, Australia
| | - Joanne Loader
- Endeavour Veterinary Ecology, Toorbul, Queensland, Australia
| | - Adam Polkinghorne
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Peter Timms
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
- * E-mail:
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Molecular Dynamics and Mode of Transmission of Koala Retrovirus as It Invades and Spreads through a Wild Queensland Koala Population. J Virol 2017; 92:JVI.01871-17. [PMID: 29237837 DOI: 10.1128/jvi.01871-17] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 12/02/2017] [Indexed: 12/31/2022] Open
Abstract
The recent acquisition of a novel retrovirus (KoRV) by koalas (Phascolarctos cinereus) has created new opportunities for retroviral research and new challenges for koala conservation. There are currently two major subtypes of KoRV: KoRV-A, which is believed to be endogenous only in koalas from the northern part of Australia, and KoRV-B, which appears to be exogenous. Understanding and management of these subtypes require population level studies of their prevalence and diversity, especially when coinfected in the same population, and investigations of their modes of transmission in the wild. Toward this end, we studied a wild Queensland koala population of 290 animals over a 5-year period and investigated the prevalence, diversity and mode of transmission of KoRV-A and KoRV-B. We found KoRV-A to have an infection level of 100% in the population, with all animals sharing the same dominant envelope protein sequence. In contrast, the KoRV-B infection prevalence was only 24%, with 21 different envelope protein sequence variants found in the 83 KoRV-B-positive animals. Linked to severe disease outcomes, a significant association between KoRV-B positivity and both chlamydial disease and neoplasia was found in the population. Transmission of KoRV-B was found at a rate of 3% via adult-to-adult contact per year, while there was a 100% rate of KoRV-B-positive mothers transmitting the virus to their joeys. Collectively, these findings demonstrate KoRV-B as the pathogenic subtype in this wild koala population and inform future intervention strategies with subtype variation and transmission data.
IMPORTANCE KoRV represents a unique opportunity to study a relatively young retrovirus as it goes through its molecular evolution in both an endogenous form and a more recently evolved exogenous form. The endogenous form, KoRV-A, now appears to have stably and completely established itself in Northern Australian koala populations and is progressing south. Conversely, the exogenous form, KoRV-B, is undergoing continuous mutation and spread in the north and, as yet, has not reached all southern koala populations. We can now link KoRV-B to neoplasia and chlamydial disease in both wild and captive koalas, making it an imminent threat to this already vulnerable species. This work represents the largest study of koalas in a wild population with respect to KoRV-A/KoRV-B-infected/coinfected animals and the linkage of this infection to chlamydial disease, neoplasia, viral evolution, and spread.
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McCallum H, Kerlin DH, Ellis W, Carrick F. Assessing the significance of endemic disease in conservation-koalas, chlamydia, and koala retrovirus as a case study. Conserv Lett 2017. [DOI: 10.1111/conl.12425] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Hamish McCallum
- Griffith School of Environment and Environmental Futures Research Institute; Griffith University; Nathan Queensland Australia
| | - Douglas H. Kerlin
- Environmental Futures Research Institute; Griffith University; Nathan Queensland 4111 Australia
| | - William Ellis
- School of Agriculture and Food Science; The University of Queensland; Brisbane Queensland Australia
| | - Frank Carrick
- Koala Study Program, Centre for Mined Land Rehabilitation; The University of Queensland; Brisbane Queensland Australia
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Jelocnik M, Islam MM, Madden D, Jenkins C, Branley J, Carver S, Polkinghorne A. Development and evaluation of rapid novel isothermal amplification assays for important veterinary pathogens: Chlamydia psittaci and Chlamydia pecorum. PeerJ 2017; 5:e3799. [PMID: 28929022 PMCID: PMC5592900 DOI: 10.7717/peerj.3799] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 08/22/2017] [Indexed: 11/20/2022] Open
Abstract
Background Chlamydia psittaci and Chlamydia pecorum are important veterinary pathogens, with the former also being responsible for zoonoses, and the latter adversely affecting koala populations in Australia and livestock globally. The rapid detection of these organisms is still challenging, particularly at the point-of-care (POC). In the present study, we developed and evaluated rapid, sensitive and robust C. psittaci-specific and C. pecorum-specific Loop Mediated Isothermal Amplification (LAMP) assays for detection of these pathogens. Methods and Materials The LAMP assays, performed in a Genie III real-time fluorometer, targeted a 263 bp region of the C. psittaci-specific Cps_0607 gene or a 209 bp region of a C. pecorum-specific conserved gene CpecG_0573, and were evaluated using a range of samples previously screened using species-specific quantitative PCRs (qPCRs). Species-specificity for C. psittaci and C. pecorum LAMP targets was tested against DNA samples from related chlamydial species and a range of other bacteria. In order to evaluate pathogen detection in clinical samples, C. psittaci LAMP was evaluated using a total of 26 DNA extracts from clinical samples from equine and avian hosts, while for C. pecorum LAMP, we tested a total of 63 DNA extracts from clinical samples from koala, sheep and cattle hosts. A subset of 36 C. pecorum samples was also tested in a thermal cycler (instead of a real-time fluorometer) using newly developed LAMP and results were determined as an end point detection. We also evaluated rapid swab processing (without DNA extraction) to assess the robustness of these assays. Results Both LAMP assays were demonstrated to species-specific, highly reproducible and to be able to detect as little as 10 genome copy number/reaction, with a mean amplification time of 14 and 24 min for C. psittaci and C. pecorum, respectively. When testing clinical samples, the overall congruence between the newly developed LAMP assays and qPCR was 92.3% for C. psittaci (91.7% sensitivity and 92.9% specificity); and 84.1% for C. pecorum (90.6% sensitivity and 77.4% specificity). For a subset of 36 C. pecorum samples tested in a thermal cycler using newly developed LAMP, we observed 34/36 (94.4%) samples result being congruent between LAMP performed in fluorometer and in thermal cycler. Rapid swab processing method evaluated in this study also allows for chlamydial DNA detection using LAMP. Discussion In this study, we describe the development of novel, rapid and robust C. psittaci-specific and C. pecorum-specific LAMP assays that are able to detect these bacteria in clinical samples in either the laboratory or POC settings. With further development and a focus on the preparation of these assays at the POC, it is anticipated that both tests may fill an important niche in the repertoire of ancillary diagnostic tools available to clinicians.
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Affiliation(s)
- Martina Jelocnik
- Centre for Animal Health Innovation, University of the Sunshine Coast, Maroochydore, Queensland, Australia
| | - Md Mominul Islam
- Centre for Animal Health Innovation, University of the Sunshine Coast, Maroochydore, Queensland, Australia
| | - Danielle Madden
- Centre for Animal Health Innovation, University of the Sunshine Coast, Maroochydore, Queensland, Australia
| | - Cheryl Jenkins
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, New South Wales, Australia
| | - James Branley
- Nepean Hospital, Penrith, New South Wales, Australia
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Adam Polkinghorne
- Centre for Animal Health Innovation, University of the Sunshine Coast, Maroochydore, Queensland, Australia
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30
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Waugh CA, Hanger J, Loader J, King A, Hobbs M, Johnson R, Timms P. Infection with koala retrovirus subgroup B (KoRV-B), but not KoRV-A, is associated with chlamydial disease in free-ranging koalas (Phascolarctos cinereus). Sci Rep 2017; 7:134. [PMID: 28273935 PMCID: PMC5427818 DOI: 10.1038/s41598-017-00137-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 02/09/2017] [Indexed: 02/02/2023] Open
Abstract
The virulence of chlamydial infection in wild koalas is highly variable between individuals. Some koalas can be infected (PCR positive) with Chlamydia for long periods but remain asymptomatic, whereas others develop clinical disease. Chlamydia in the koala has traditionally been studied without regard to coinfection with other pathogens, although koalas are usually subject to infection with koala retrovirus (KoRV). Retroviruses can be immunosuppressive, and there is evidence of an immunosuppressive effect of KoRV in vitro. Originally thought to be a single endogenous strain, a new, potentially more virulent exogenous variant (KoRV-B) was recently reported. We hypothesized that KoRV-B might significantly alter chlamydial disease outcomes in koalas, presumably via immunosuppression. By studying sub-groups of Chlamydia and KoRV infected koalas in the wild, we found that neither total KoRV load (either viraemia or proviral copies per genome), nor chlamydial infection level or strain type, was significantly associated with chlamydial disease risk. However, PCR positivity with KoRV-B was significantly associated with chlamydial disease in koalas (p = 0.02961). This represents an example of a recently evolved virus variant that may be predisposing its host (the koala) to overt clinical disease when co-infected with an otherwise asymptomatic bacterial pathogen (Chlamydia).
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Affiliation(s)
- Courtney A Waugh
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, 4558, Queensland, Australia.,Department of Biology, Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | - Jonathan Hanger
- Endeavour Veterinary Ecology, 1695 Pumicestone Rd, Toorbul, 4510, Queensland, Australia
| | - Joanne Loader
- Endeavour Veterinary Ecology, 1695 Pumicestone Rd, Toorbul, 4510, Queensland, Australia
| | - Andrew King
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, NSW, 2010, Australia
| | - Matthew Hobbs
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, NSW, 2010, Australia
| | - Rebecca Johnson
- Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney, NSW, 2010, Australia
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, 4558, Queensland, Australia.
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31
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Waugh C, Austin R, Polkinghorne A, Timms P. Treatment of Chlamydia-associated ocular disease via a recombinant protein based vaccine in the koala (Phascolarctos cinereus). Biologicals 2016; 44:588-590. [PMID: 27707559 DOI: 10.1016/j.biologicals.2016.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 08/23/2016] [Accepted: 09/13/2016] [Indexed: 10/20/2022] Open
Abstract
Koalas (Phascolarctos cinereus) are affected by debilitating chlamydial disease that can lead to blindness, infertility, and death. The causative agent is the intracellular bacterium Chlamydia pecorum. While antibiotics can be used to treat koala chlamydial infection, they are often ineffective or cause severe dysbiosis to the animal's unique gut flora. Recent work has progressed on the development of a protective vaccine for Chlamydia in the koala. This study demonstrates that the use of a vaccine can have a positive effect in koalas already with clinical signs of ocular disease, suggesting a possible therapeutic effect and an alternative to antibiotic therapy.
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Affiliation(s)
- Courtney Waugh
- Faculty of Science, Health, Education and Engineering, The University of the Sunshine Coast, Queensland, Australia.
| | - Ray Austin
- Keen Street Veterinary Clinic, Lismore, New South Wales, Australia
| | - Adam Polkinghorne
- Faculty of Science, Health, Education and Engineering, The University of the Sunshine Coast, Queensland, Australia.
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, The University of the Sunshine Coast, Queensland, Australia.
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32
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Lawrence A, Fraser T, Gillett A, Tyndall JDA, Timms P, Polkinghorne A, Huston WM. Chlamydia Serine Protease Inhibitor, targeting HtrA, as a New Treatment for Koala Chlamydia infection. Sci Rep 2016; 6:31466. [PMID: 27530689 PMCID: PMC4987629 DOI: 10.1038/srep31466] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 07/20/2016] [Indexed: 01/01/2023] Open
Abstract
The koala, an iconic marsupial native to Australia, is a threatened species in many parts of the country. One major factor in the decline is disease caused by infection with Chlamydia. Current therapeutic strategies to treat chlamydiosis in the koala are limited. This study examines the effectiveness of an inhibitor, JO146, which targets the HtrA serine protease for treatment of C. pecorum and C. pneumoniae in vitro and ex vivo with the aim of developing a novel therapeutic for koala Chlamydia infections. Clinical isolates from koalas were examined for their susceptibility to JO146. In vitro studies demonstrated that treatment with JO146 during the mid-replicative phase of C. pecorum or C. pneumoniae infections resulted in a significant loss of infectious progeny. Ex vivo primary koala tissue cultures were used to demonstrate the efficacy of JO146 and the non-toxic nature of this compound on peripheral blood mononuclear cells and primary cell lines established from koala tissues collected at necropsy. Our results suggest that inhibition of the serine protease HtrA could be a novel treatment strategy for chlamydiosis in koalas.
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Affiliation(s)
- Amba Lawrence
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, QLD, 4059, Australia
| | - Tamieka Fraser
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydoore, QLD, 4558, Australia
| | - Amber Gillett
- Australia Zoo Wildlife Hospital, Beerwah, QLD, 4519, Australia
| | - Joel D A Tyndall
- New Zealand's National School of Pharmacy, University of Otago, Dunedin 9054 New Zealand
| | - Peter Timms
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydoore, QLD, 4558, Australia
| | - Adam Polkinghorne
- Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydoore, QLD, 4558, Australia
| | - Wilhelmina M Huston
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, QLD, 4059, Australia.,School of Life Sciences, University of Technology Sydney, Broadway, NSW, 2007, Australia
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A non-invasive tool for assessing pathogen prevalence in koala (Phascolarctos cinereus) populations: detection of Chlamydia pecorum and koala retrovirus (KoRV) DNA in genetic material sourced from scats. CONSERV GENET RESOUR 2016. [DOI: 10.1007/s12686-016-0574-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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PREVALENCE AND PATHOLOGIC FEATURES OF CHLAMYDIA PECORUM INFECTIONS IN SOUTH AUSTRALIAN KOALAS (PHASCOLARCTOS CINEREUS). J Wildl Dis 2016; 52:301-6. [PMID: 26967132 DOI: 10.7589/2015-05-120] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Chlamydia pecorum infection is highly prevalent in many koala ( Phascolarctos cinereus ) populations in the eastern states of Australia, causing ocular and urogenital tract disease. In contrast, the current prevalence of chlamydiosis in South Australian (SA) koalas is largely unknown, with few reports of clinical cases. We examined 65 SA rescued wild koalas at necropsy and collected ocular and urogenital swabs for the detection of C. pecorum by PCR. We detected C. pecorum in ocular or urogenital swabs from 57 koalas (88%), and 34 koalas were positive at both ocular and urogenital sites. Clinically overt chlamydial disease was present in only 12 (21%) positive koalas. Gross lesions were often externally inapparent as they affected the urogenital tract (n=5), and 24 infected koalas had microscopically evident lesions only. Lesions were predominantly mild and included conjunctivitis, cystitis, and urethritis. Reproductive tract disease was infrequently observed. We detected C. pecorum in 16 (28%) koalas with no evidence of chlamydial disease, suggesting the presence of subclinical carriers in this population. Based on these findings, chlamydiosis has a higher occurrence in SA koala populations than previously thought, but is most often mild and does not always result in overt clinical disease; inapparent and subclinical infections appear common. Further studies of the prevalence in wild-caught SA koalas are needed along with research into the host and bacterial factors that may influence disease outcome in these animals.
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35
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Waugh C, Khan SA, Carver S, Hanger J, Loader J, Polkinghorne A, Beagley K, Timms P. A Prototype Recombinant-Protein Based Chlamydia pecorum Vaccine Results in Reduced Chlamydial Burden and Less Clinical Disease in Free-Ranging Koalas (Phascolarctos cinereus). PLoS One 2016; 11:e0146934. [PMID: 26756624 PMCID: PMC4710501 DOI: 10.1371/journal.pone.0146934] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 12/23/2015] [Indexed: 11/19/2022] Open
Abstract
Diseases associated with Chlamydia pecorum infection are a major cause of decline in koala populations in Australia. While koalas in care can generally be treated, a vaccine is considered the only option to effectively reduce the threat of infection and disease at the population level. In the current study, we vaccinated 30 free-ranging koalas with a prototype Chlamydia pecorum vaccine consisting of a recombinant chlamydial MOMP adjuvanted with an immune stimulating complex. An additional cohort of 30 animals did not receive any vaccine and acted as comparison controls. Animals accepted into this study were either uninfected (Chlamydia PCR negative) at time of initial vaccination, or infected (C. pecorum positive) at either urogenital (UGT) and/or ocular sites (Oc), but with no clinical signs of chlamydial disease. All koalas were vaccinated / sampled and then re-released into their natural habitat before re-capturing and re-sampling at 6 and 12 months. All vaccinated koalas produced a strong immune response to the vaccine, as indicated by high titres of specific plasma antibodies. The incidence of new infections in vaccinated koalas over the 12-month period post-vaccination was slightly less than koalas in the control group, however, this was not statistically significant. Importantly though, the vaccine was able to significantly reduce the infectious load in animals that were Chlamydia positive at the time of vaccination. This effect was evident at both the Oc and UGT sites and was stronger at 6 months than at 12 months post-vaccination. Finally, the vaccine was also able to reduce the number of animals that progressed to disease during the 12-month period. While the sample sizes were small (statistically speaking), results were nonetheless striking. This study highlights the potential for successful development of a Chlamydia vaccine for koalas in a wild setting.
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Affiliation(s)
- Courtney Waugh
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs, 4558, Queensland, Australia
| | - Shahneaz Ali Khan
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, 4059, Queensland, Australia
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Jonathan Hanger
- Endeavour Veterinary Ecology, 1695 Pumicestone Rd, Toorbul, 4510, Queensland, Australia
| | - Joanne Loader
- Endeavour Veterinary Ecology, 1695 Pumicestone Rd, Toorbul, 4510, Queensland, Australia
| | - Adam Polkinghorne
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs, 4558, Queensland, Australia
| | - Kenneth Beagley
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, 4059, Queensland, Australia
| | - Peter Timms
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs, 4558, Queensland, Australia
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, 4059, Queensland, Australia
- * E-mail:
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Adams-Hosking C, McBride MF, Baxter G, Burgman M, de Villiers D, Kavanagh R, Lawler I, Lunney D, Melzer A, Menkhorst P, Molsher R, Moore BD, Phalen D, Rhodes JR, Todd C, Whisson D, McAlpine CA. Use of expert knowledge to elicit population trends for the koala (Phascolarctos cinereus). DIVERS DISTRIB 2016. [DOI: 10.1111/ddi.12400] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Christine Adams-Hosking
- School of Geography, Planning and Environmental Management; Global Change Institute, The University of Queensland; Brisbane Qld 4072 Australia
| | - Marissa F. McBride
- School of Botany; The University of Melbourne; Melbourne Vic. 3010 Australia
- Department of Biosciences; University of Helsinki; Helsinki 00014 Finland
| | - Greg Baxter
- School of Geography Planning and Environmental Management; The University of Queensland, Landscape Ecology and Conservation Group; Brisbane Qld 4072 Australia
| | - Mark Burgman
- School of Botany, Environmental Science; The University of Melbourne; Melbourne Vic. 3010 Australia
| | - Deidre de Villiers
- Endeavour Veterinary Ecology; 1695 Pumicestone Rd Toorbul Qld 4510 Australia
| | - Rodney Kavanagh
- The Australian National University; Research School of Biology; Canberra 0200 Australia; Niche Environment and Heritage; PO Box 2443 North Parramatta NSW 2150 Australia
| | - Ivan Lawler
- Wildlife Heritage and Marine Division; Department of the Environment; Marine and Freshwater Species Conservation Section; Canberra ACT 2700 Australia
| | - Daniel Lunney
- Office of Environment and Heritage NSW; Hurstville NSW 2220 Australia
- School of Biological Sciences; University of Sydney; Sydney NSW 2006 Australia
| | - Alistair Melzer
- Koala Research Centre of Central Queensland; School of Medical and Applied Sciences; CQ University; Rockhampton Qld 4702 Australia
| | - Peter Menkhorst
- Department of Environment, Land, Water & Planning; Arthur Rylah Institute for Environmental Research; Heidelberg Vic. 3084 Australia
| | - Robyn Molsher
- Department of Environment, Water and Natural Resources; PO Box 39 Kingscote SA 5223 Australia
| | - Ben D. Moore
- Hawkesbury Institute for the Environment; Western Sydney University; Locked Bag 1797 Penrith 2751 NSW Australia
| | - David Phalen
- Faculty of Veterinary Science; University of Sydney; Sydney NSW 2006 Australia
| | - Jonathan R. Rhodes
- ARC Centre of Excellence for Environmental Decisions; The University of Queensland; Brisbane Qld 4072 Australia
| | - Charles Todd
- Department of Environment, Land, Water & Planning; Arthur Rylah Institute for Environmental Research; Heidelberg Vic. 3084 Australia
| | - Desley Whisson
- School of Life and Environmental Sciences; Faculty of Science Engineering & Built Environment; Deakin University; Burwood Vic. 3125 Australia
| | - Clive A. McAlpine
- Landscape Ecology and Conservation Group; School of Geography, Planning, and Environmental Management; The University of Queensland; Brisbane Qld 4072 Australia
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De Puysseleyr L, De Puysseleyr K, Braeckman L, Morré SA, Cox E, Vanrompay D. Assessment of Chlamydia suis Infection in Pig Farmers. Transbound Emerg Dis 2015; 64:826-833. [PMID: 26576707 DOI: 10.1111/tbed.12446] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Indexed: 11/27/2022]
Abstract
Chlamydia suis infections are endemic in domestic pigs in Europe and can lead to conjunctivitis, pneumonia, enteritis and reproductive failure. Currently, the knowledge on the zoonotic potential of C. suis is limited. Moreover, the last decades, porcine tetracycline resistant C. suis strains have been isolated, which interfere with treatment of chlamydial infections. In this study, the presence of C. suis was examined on nine Belgian pig farms, using Chlamydia culture and a C. suis specific real-time PCR in both pigs and farmers. In addition to diagnosis for C. suis, the farmers' samples were examined using a Chlamydia trachomatis PCR. Additionally, the Chlamydia isolates were tested for the presence of the tet(C) resistance gene. C. DNA was demonstrated in pigs on all farms, and eight of nine farmers were positive in at least one anatomical site. None of the farmers tested positive for C. trachomatis. Chlamydia suis isolates were obtained from pigs of eight farms. Nine porcine C. suis isolates possessing a tet(C) gene were retrieved, originating from three farms. Moreover, C. suis isolates were identified in three human samples, including one pharyngeal and two rectal samples. These findings suggest further research on the zoonotic transfer of C. suis from pigs to humans is needed.
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Affiliation(s)
- L De Puysseleyr
- Lab of Immunology and Animal Biotechnology, Department of Animal Production, Faculty of Bioscience Engineering, University of Ghent, Ghent, Belgium
| | - K De Puysseleyr
- Lab of Immunology and Animal Biotechnology, Department of Animal Production, Faculty of Bioscience Engineering, University of Ghent, Ghent, Belgium
| | - L Braeckman
- Department of Public Health, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - S A Morré
- Department of Medical Microbiology & Infection Control, Laboratory of Immunogenetics, VU University Medical Center, Amsterdam, The Netherlands.,Institute for Public Health Genomics (IPHG), Department of Genetics and Cell Biology, GROW (School for Oncology & Developmental Biology), Faculty of Health, Medicine & Life Sciences, University of Maastricht, Maastricht, The Netherlands
| | - E Cox
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, University of Ghent, Ghent, Belgium
| | - D Vanrompay
- Lab of Immunology and Animal Biotechnology, Department of Animal Production, Faculty of Bioscience Engineering, University of Ghent, Ghent, Belgium
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Morris KM, Mathew M, Waugh C, Ujvari B, Timms P, Polkinghorne A, Belov K. Identification, characterisation and expression analysis of natural killer receptor genes in Chlamydia pecorum infected koalas (Phascolarctos cinereus). BMC Genomics 2015; 16:796. [PMID: 26471184 PMCID: PMC4608214 DOI: 10.1186/s12864-015-2035-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 10/08/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Koalas (Phascolarctos cinereus), an iconic Australian marsupial, are being heavily impacted by the spread of Chlamydia pecorum, an obligate intracellular bacterial pathogen. Koalas vary in their response to this pathogen, with some showing no symptoms, while others suffer severe symptoms leading to infertility, blindness or death. Little is known about the pathology of this disease and the immune response against it in this host. Studies have demonstrated that natural killer (NK) cells, key components of the innate immune system, are involved in the immune response to chlamydial infections in humans. These cells can directly lyse cells infected by intracellular pathogens and their ability to recognise these infected cells is mediated through NK receptors on their surface. These are encoded in two regions of the genome, the leukocyte receptor complex (LRC) and the natural killer complex (NKC). These two families evolve rapidly and different repertoires of genes, which have evolved by gene duplication, are seen in different species. METHODS In this study we aimed to characterise genes belonging to the NK receptor clusters in the koala by searching available koala transcriptomes using a combination of search methods. We developed a qPCR assay to quantify relative expression of four genes, two encoded within the NK receptor cluster (CLEC1B, CLEC4E) and two known to play a role in NK response to Chalmydia in humans (NCR3, PRF1). RESULTS We found that the NK receptor repertoire of the koala closely resembles that of the Tasmanian devil, with minimal genes in the NKC, but with lineage specific expansions in the LRC. Additional genes important for NK cell activity, NCR3 and PRF1, were also identified and characterised. In a preliminary study to investigate whether these genes are involved in the koala immune response to infection by its chlamydial pathogen, C. pecorum, we investigated the expression of four genes in koalas with active chlamydia infection, those with past infection and those without infection using qPCR. This analysis revealed that one of these four, CLEC4E, may be upregulated in response to chlamydia infection. CONCLUSION We have characterised genes of the NKC and LRC in koalas and have discovered evidence that one of these genes may be upregulated in koalas with chlamydia, suggesting that these receptors may play a role in the immune response of koalas to chlamydia infection.
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Affiliation(s)
- Katrina M Morris
- Faculty of Veterinary Science, University of Sydney, Camperdown, NSW, Australia.
| | - Marina Mathew
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Brisbane, QLD, Australia.
| | - Courtney Waugh
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Brisbane, QLD, Australia. .,Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia.
| | - Beata Ujvari
- Faculty of Veterinary Science, University of Sydney, Camperdown, NSW, Australia. .,Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Geelong, VIC, Australia.
| | - Peter Timms
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Brisbane, QLD, Australia. .,Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia.
| | - Adam Polkinghorne
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Brisbane, QLD, Australia. .,Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia.
| | - Katherine Belov
- Faculty of Veterinary Science, University of Sydney, Camperdown, NSW, Australia.
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THE PARADOX OF EUTHANIZING KOALAS (PHASCOLARCTOS CINEREUS) TO SAVE POPULATIONS FROM ELIMINATION. J Wildl Dis 2015; 51:833-42. [PMID: 26280878 DOI: 10.7589/2014-12-278] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Koala (Phascolarctos cinereus) populations in the wild are in sharp decline in Australia due to deforestation, road accidents, dog attacks, and disease from infection with sexually transmitted Chlamydia spp. Severely diseased koalas that are captured are euthanized for humane reasons because antibiotics are not effective. Paradoxically, we propose that euthanizing more koalas could help to increase koala population numbers. We investigated the potential impact of systematically euthanizing diseased koalas. Using data from a well-studied koala population, and an individual-based computer simulation model, we predict that such a program would result in a larger population of koalas after 7 yr than would exist without the program. If terminally diseased and sterile koalas are euthanized and other infected captured koalas are given antibiotics, chlamydial infection could be eliminated and population growth observed after 4 yr. The practical implementation of such a program would be facilitated with further development of tools to diagnose infection and internal disease in the field.
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Abstract
Toll-like receptors (TLRs) play a crucial role in the early defence against invading pathogens, yet our understanding of TLRs in marsupial immunity is limited. Here, we describe the characterisation of nine TLRs from a koala immune tissue transcriptome and one TLR from a draft sequence of the koala genome and the subsequent development of an assay to study genetic diversity in these genes. We surveyed genetic diversity in 20 koalas from New South Wales, Australia and showed that one gene, TLR10 is monomorphic, while the other nine TLR genes have between two and 12 alleles. 40 SNPs (16 non-synonymous) were identified across the ten TLR genes. These markers provide a springboard to future studies on innate immunity in the koala, a species under threat from two major infectious diseases.
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Comparison of subcutaneous versus intranasal immunization of male koalas (Phascolarctos cinereus) for induction of mucosal and systemic immunity against Chlamydia pecorum. Vaccine 2015; 33:855-60. [PMID: 25562793 DOI: 10.1016/j.vaccine.2014.12.052] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/20/2014] [Accepted: 12/19/2014] [Indexed: 01/04/2023]
Abstract
Chlamydia pecorum infections are debilitating in the koala, contributing significantly to morbidity and mortality, with current antibiotic treatments having minimal success and adversely affecting gut microflora. This, combined with the sometimes-asymptomatic nature of the infection, suggests that an efficacious anti-chlamydial vaccine is required to control chlamydial infections in the koala. To date vaccination studies have focused primarily on female koalas, however, given the physiological differences between male and female reproductive tracts, we tested the efficacy of a vaccine in 12 captive male koalas. We evaluated the potential of both subcutaneous and intranasal vaccine delivery to elicit mucosal immunity in male koalas. Our results showed that both intranasal and subcutaneous delivery of a vaccine consisting of C. pecorum major outer membrane protein (MOMP) and the adjuvant immunostimulating complex (ISC) induced significant immune responses in male koalas. Subcutaneous immunization elicited stronger cell-mediated responses in peripheral blood lymphocytes (PBL), and greater plasma antibody levels whereas the intranasal immunization elicited stronger humoral responses in urogenital tract (UGT) secretions. This is the first time a Chlamydia vaccine has been tested in the male koala and the first assessment of a mucosal vaccination route in this species. Our results suggest that vaccination of male koalas can elicit mucosal immunity and could contribute to the long-term survivability of wild populations of the koala.
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Mathew M, Waugh C, Beagley KW, Timms P, Polkinghorne A. Interleukin 17A is an immune marker for chlamydial disease severity and pathogenesis in the koala (Phascolarctos cinereus). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 46:423-429. [PMID: 24915607 DOI: 10.1016/j.dci.2014.05.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 05/22/2014] [Accepted: 05/22/2014] [Indexed: 06/03/2023]
Abstract
The koala (Phascolarctos cinereus) is an iconic Australian marsupial species that is facing many threats to its survival. Chlamydia pecorum infections are a significant contributor to this ongoing decline. A major limiting factor in our ability to manage and control chlamydial disease in koalas is a limited understanding of the koala's cell-mediated immune response to infections by this bacterial pathogen. To identify immunological markers associated with chlamydial infection and disease in koalas, we used koala-specific Quantitative Real Time PCR (qrtPCR) assays to profile the cytokine responses of Peripheral Blood Mononuclear Cells (PBMCs) collected from 41 koalas with different stages of chlamydial disease. Target cytokines included the principal Th1 (Interferon gamma; IFNγ), Th2 (Interleukin 10; IL10), and pro-inflammatory cytokines (Tumor Necrosis Factor alpha; TNFα). A novel koala-specific IL17A qrtPCR assay was also developed as part of this study to quantitate the gene expression of this Th17 cytokine in koalas. A statistically significant higher IL17A gene expression was observed in animals with current chlamydial disease compared to animals with asymptomatic chlamydial infection. A modest up-regulation of pro-inflammatory cytokines, such as TNFα and IFNγ, was also observed in these animals with signs of current chlamydial disease. IL10 gene expression was not evident in the majority of animals from both groups. Future longitudinal studies are now required to confirm the role played by cytokines in pathology and/or protection against C. pecorum infection in the koala.
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Affiliation(s)
- Marina Mathew
- Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia
| | - Courtney Waugh
- Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs 4558, QLD, Australia
| | - Kenneth W Beagley
- Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia
| | - Peter Timms
- Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs 4558, QLD, Australia
| | - Adam Polkinghorne
- Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs 4558, QLD, Australia.
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Khan SA, Waugh C, Rawlinson G, Brumm J, Nilsson K, Gerdts V, Potter A, Polkinghorne A, Beagley K, Timms P. Vaccination of koalas (Phascolarctos cinereus) with a recombinant chlamydial major outer membrane protein adjuvanted with poly I:C, a host defense peptide and polyphosphazine, elicits strong and long lasting cellular and humoral immune responses. Vaccine 2014; 32:5781-6. [PMID: 25196393 DOI: 10.1016/j.vaccine.2014.08.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/26/2014] [Accepted: 08/15/2014] [Indexed: 01/08/2023]
Abstract
Chlamydial infections are wide spread in koalas across their range and a solution to this debilitating disease has been sought for over a decade. Antibiotics are the currently accepted therapeutic measure, but are not an effective treatment due to the asymptomatic nature of some infections and a low efficacy rate. Thus, a vaccine would be an ideal way to address this infectious disease threat in the wild. Previous vaccine trials have used a three-dose regimen; however this is very difficult to apply in the field as it would require multiple capture events, which are stressful and invasive processes for the koala. In addition, it requires skilled koala handlers and a significant monetary investment. To overcome these challenges, in this study we utilized a polyphosphazine based poly I:C and a host defense peptide adjuvant combined with recombinant chlamydial major outer membrane protein (rMOMP) antigen to induce long lasting (54 weeks) cellular and humoral immunity in female koalas with a novel single immunizing dose. Immunized koalas produced a strong IgG response in plasma, as well as at mucosal sites. Moreover, they showed high levels of C. pecorum specific neutralizing antibodies in the plasma as well as vaginal and conjunctival secretions. Lastly, Chlamydia-specific lymphocyte proliferation responses were produced against both whole chlamydial elementary bodies and rMOMP protein, over the 12-month period. The results of this study suggest that a single dose rMOMP vaccine incorporating a poly I:C, host defense peptide and polyphosphazine adjuvant is able to stimulate both arms of the immune system in koalas, thereby providing an alternative to antibiotic treatment and/or a three-dose vaccine regime.
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Affiliation(s)
- Shahneaz Ali Khan
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, QLD 4059, Australia.
| | - Courtney Waugh
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, QLD 4059, Australia; Faculty of Science, Health, Education & Engineering, University of the Sunshine Coast, Locked Bag 4, Maroochydore DC, QLD 4558, Australia.
| | - Galit Rawlinson
- Lone Pine Koala Sanctuary, Fig Tree Pocket, QLD 4519, Australia.
| | - Jacqui Brumm
- Lone Pine Koala Sanctuary, Fig Tree Pocket, QLD 4519, Australia.
| | - Karen Nilsson
- Lone Pine Koala Sanctuary, Fig Tree Pocket, QLD 4519, Australia.
| | - Volker Gerdts
- Vaccine and Infectious Disease Organizations, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada.
| | - Andrew Potter
- Vaccine and Infectious Disease Organizations, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada.
| | - Adam Polkinghorne
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, QLD 4059, Australia; Faculty of Science, Health, Education & Engineering, University of the Sunshine Coast, Locked Bag 4, Maroochydore DC, QLD 4558, Australia.
| | - Kenneth Beagley
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, QLD 4059, Australia.
| | - Peter Timms
- Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, QLD 4059, Australia; Faculty of Science, Health, Education & Engineering, University of the Sunshine Coast, Locked Bag 4, Maroochydore DC, QLD 4558, Australia.
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Evaluation of the relationship between Chlamydia pecorum sequence types and disease using a species-specific multi-locus sequence typing scheme (MLST). Vet Microbiol 2014; 174:214-22. [PMID: 25223647 DOI: 10.1016/j.vetmic.2014.08.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/28/2014] [Accepted: 08/14/2014] [Indexed: 11/22/2022]
Abstract
Chlamydia pecorum is globally associated with several ovine diseases including keratoconjunctivitis and polyarthritis. The exact relationship between the variety of C. pecorum strains reported and the diseases described in sheep remains unclear, challenging efforts to accurately diagnose and manage infected flocks. In the present study, we applied C. pecorum multi-locus sequence typing (MLST) to C. pecorum positive samples collected from sympatric flocks of Australian sheep presenting with conjunctivitis, conjunctivitis with polyarthritis, or polyarthritis only and with no clinical disease (NCD) in order to elucidate the exact relationships between the infecting strains and the range of diseases. Using Bayesian phylogenetic and cluster analyses on 62 C. pecorum positive ocular, vaginal and rectal swab samples from sheep presenting with a range of diseases and in a comparison to C. pecorum sequence types (STs) from other hosts, one ST (ST 23) was recognised as a globally distributed strain associated with ovine and bovine diseases such as polyarthritis and encephalomyelitis. A second ST (ST 69) presently only described in Australian animals, was detected in association with ovine as well as koala chlamydial infections. The majority of vaginal and rectal C. pecorum STs from animals with NCD and/or anatomical sites with no clinical signs of disease in diseased animals, clustered together in a separate group, by both analyses. Furthermore, 8/13 detected STs were novel. This study provides a platform for strain selection for further research into the pathogenic potential of C. pecorum in animals and highlights targets for potential strain-specific diagnostic test development.
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Bachmann NL, Fraser TA, Bertelli C, Jelocnik M, Gillett A, Funnell O, Flanagan C, Myers GSA, Timms P, Polkinghorne A. Comparative genomics of koala, cattle and sheep strains of Chlamydia pecorum. BMC Genomics 2014; 15:667. [PMID: 25106440 PMCID: PMC4137089 DOI: 10.1186/1471-2164-15-667] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 07/31/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Chlamydia pecorum is an important pathogen of domesticated livestock including sheep, cattle and pigs. This pathogen is also a key factor in the decline of the koala in Australia. We sequenced the genomes of three koala C. pecorum strains, isolated from the urogenital tracts and conjunctiva of diseased koalas. The genome of the C. pecorum VR629 (IPA) strain, isolated from a sheep with polyarthritis, was also sequenced. RESULTS Comparisons of the draft C. pecorum genomes against the complete genomes of livestock C. pecorum isolates revealed that these strains have a conserved gene content and order, sharing a nucleotide sequence similarity > 98%. Single nucleotide polymorphisms (SNPs) appear to be key factors in understanding the adaptive process. Two regions of the chromosome were found to be accumulating a large number of SNPs within the koala strains. These regions include the Chlamydia plasticity zone, which contains two cytotoxin genes (toxA and toxB), and a 77 kbp region that codes for putative type III effector proteins. In one koala strain (MC/MarsBar), the toxB gene was truncated by a premature stop codon but is full-length in IPTaLE and DBDeUG. Another five pseudogenes were also identified, two unique to the urogenital strains C. pecorum MC/MarsBar and C. pecorum DBDeUG, respectively, while three were unique to the koala C. pecorum conjunctival isolate IPTaLE. An examination of the distribution of these pseudogenes in C. pecorum strains from a variety of koala populations, alongside a number of sheep and cattle C. pecorum positive samples from Australian livestock, confirmed the presence of four predicted pseudogenes in koala C. pecorum clinical samples. Consistent with our genomics analyses, none of these pseudogenes were observed in the livestock C. pecorum samples examined. Interestingly, three SNPs resulting in pseudogenes identified in the IPTaLE isolate were not found in any other C. pecorum strain analysed, raising questions over the origin of these point mutations. CONCLUSIONS The genomic data revealed that variation between C. pecorum strains were mainly due to the accumulation of SNPs, some of which cause gene inactivation. The identification of these genetic differences will provide the basis for further studies to understand the biology and evolution of this important animal pathogen.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Adam Polkinghorne
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs 4558, Queensland, Australia.
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Host adaptation of Chlamydia pecorum towards low virulence evident in co-evolution of the ompA, incA, and ORF663 Loci. PLoS One 2014; 9:e103615. [PMID: 25084532 PMCID: PMC4118914 DOI: 10.1371/journal.pone.0103615] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 07/03/2014] [Indexed: 11/19/2022] Open
Abstract
Chlamydia (C.) pecorum, an obligate intracellular bacterium, may cause severe diseases in ruminants, swine and koalas, although asymptomatic infections are the norm. Recently, we identified genetic polymorphisms in the ompA, incA and ORF663 genes that potentially differentiate between high-virulence C. pecorum isolates from diseased animals and low-virulence isolates from asymptomatic animals. Here, we expand these findings by including additional ruminant, swine, and koala strains. Coding tandem repeats (CTRs) at the incA locus encoded a variable number of repeats of APA or AGA amino acid motifs. Addition of any non-APA/AGA repeat motif, such as APEVPA, APAVPA, APE, or APAPE, associated with low virulence (P<10−4), as did a high number of amino acids in all incA CTRs (P = 0.0028). In ORF663, high numbers of 15-mer CTRs correlated with low virulence (P = 0.0001). Correction for ompA phylogram position in ORF663 and incA abolished the correlation between genetic changes and virulence, demonstrating co-evolution of ompA, incA, and ORF663 towards low virulence. Pairwise divergence of ompA, incA, and ORF663 among isolates from healthy animals was significantly higher than among strains isolated from diseased animals (P≤10−5), confirming the longer evolutionary path traversed by low-virulence strains. All three markers combined identified 43 unique strains and 4 pairs of identical strains among all 57 isolates tested, demonstrating the suitability of these markers for epidemiological investigations.
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Molecular and pathological insights into Chlamydia pecorum-associated sporadic bovine encephalomyelitis (SBE) in Western Australia. BMC Vet Res 2014; 10:121. [PMID: 24884687 PMCID: PMC4064815 DOI: 10.1186/1746-6148-10-121] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 05/20/2014] [Indexed: 11/29/2022] Open
Abstract
Background Despite its global recognition as a ruminant pathogen, cases of Chlamydia pecorum infection in Australian livestock are poorly documented. In this report, a C. pecorum specific Multi Locus Sequence Analysis scheme was used to characterise the C. pecorum strains implicated in two cases of sporadic bovine encephalomyelitis confirmed by necropsy, histopathology and immunohistochemistry. This report provides the first molecular evidence for the presence of mixed infections of C. pecorum strains in Australian cattle. Case presentation Affected animals were two markedly depressed, dehydrated and blind calves, 12 and 16 weeks old. The calves were euthanized and necropsied. In one calf, a severe fibrinous polyserositis was noted with excess joint fluid in all joints whereas in the other, no significant lesions were seen. No gross abnormalities were noted in the brain of either calf. Histopathological lesions seen in both calves included: multifocal, severe, subacute meningoencephalitis with vasculitis, fibrinocellular thrombosis and malacia; diffuse, mild, acute interstitial pneumonia; and diffuse, subacute epicarditis, severe in the calf with gross serositis. Immunohistochemical labelling of chlamydial antigen in brain, spleen and lung from the two affected calves and brain from two archived cases, localised the antigen to the cytoplasm of endothelium, mesothelium and macrophages. C. pecorum specific qPCR, showed dissemination of the pathogen to multiple organs. Phylogenetic comparisons with other C. pecorum bovine strains from Australia, Europe and the USA revealed the presence of two genetically distinct sequence types (ST). The predominant ST detected in the brain, heart, lung and liver of both calves was identical to the C. pecorum ST previously described in cases of SBE. A second ST detected in an ileal tissue sample from one of the calves, clustered with previously typed faecal bovine isolates. Conclusion This report provides the first data to suggest that identical C. pecorum STs may be associated with SBE in geographically separated countries and that these may be distinct from those found in the gastrointestinal tract. This report provides a platform for further investigations into SBE and for understanding the genetic relationships that exist between C. pecorum strains detected in association with other infectious diseases in livestock.
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Liddle V, Naranjo C, Bernays M. Anterior chamber collapse syndrome in a koala. Aust Vet J 2014; 92:179-82. [PMID: 24766050 DOI: 10.1111/avj.12166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2013] [Indexed: 12/01/2022]
Abstract
BACKGROUND Anterior chamber collapse syndrome has been recognised in various species and is associated with early-life ocular disease or trauma. It is important to differentiate this acquired condition from a congenital malformation. CASE REPORT An adult female koala (Phascolarctos cinereus) was referred for assessment of buphthalmos and severe keratitis of the right eye. The degree of keratitis obstructed examination of intraocular structures. Enucleation of the affected eye was performed and the histopathological diagnosis was anterior chamber collapse syndrome and secondary glaucoma. This case contributes to the limited information available in the literature on anterior chamber collapse syndrome, a disease unique in having secondary glaucoma with minimal or no inflammation. The case also expands the literature available on ocular disease in koalas. More specifically, this is the only reported case of glaucoma, of any aetiology, in the koala.
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Affiliation(s)
- Vl Liddle
- Animal Eye Services, Underwood, Queensland, Australia
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Liddle VL. Electroretinography in the normal koala (Phascolarctos cinereus). Vet Ophthalmol 2013; 18 Suppl 1:74-80. [DOI: 10.1111/vop.12133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Vicki L. Liddle
- Animal Eye Services; Shop 14 ‘Springwood Centre’ Cnr Logan & Lexington Rds Underwood Qld 4119 Australia
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Kollipara A, Polkinghorne A, Wan C, Kanyoka P, Hanger J, Loader J, Callaghan J, Bell A, Ellis W, Fitzgibbon S, Melzer A, Beagley K, Timms P. Genetic diversity of Chlamydia pecorum strains in wild koala locations across Australia and the implications for a recombinant C. pecorum major outer membrane protein based vaccine. Vet Microbiol 2013; 167:513-22. [DOI: 10.1016/j.vetmic.2013.08.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/08/2013] [Accepted: 08/12/2013] [Indexed: 11/29/2022]
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