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Hussain-Yusuf H, Stenos J, Vincent G, Shima A, Abell S, Preece ND, Tadepalli M, Hii SF, Bowie N, Mitram K, Graves S. Screening for Rickettsia, Coxiella and Borrelia Species in Ticks from Queensland, Australia. Pathogens 2020; 9:E1016. [PMID: 33276564 PMCID: PMC7761571 DOI: 10.3390/pathogens9121016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 11/25/2022] Open
Abstract
Tick bites in Australia are linked to the transmission of a variety of infectious diseases in humans, livestock and wildlife. Despite this recognition, little is currently known about the variety of potential pathogens that are carried and transmitted by Australian ticks. In this study, we attempted to expand knowledge of Australian tick-borne bacterial pathogens by analyzing various tick species from the state of Queensland for potential human pathogens belonging to the Rickettsia, Coxiella and Borrelia genera. A total of 203 ticks, comprising of four genera and nine different tick species, were screened by specific qPCR assays. An overall Rickettsia qPCR positivity of 6.4% (13/203) was detected with rickettsial DNA found in four tick species (Ixodes holocyclus, I. tasmani, Amblyommatriguttatum, and Haemaphysalis longicornis). Amplification and analysis of several rickettsial genes from rickettsial qPCR positive samples identified sequences closely related to but genetically distinct from several previously described cultured and uncultured rickettsial species in the Rickettsia spotted fever subgroup. No ticks were positive for either Coxiella or Borrelia DNA. This work suggests that a further diversity of rickettsiae remain to be described in Australian ticks with the full importance of these bacteria to human and animal health yet to be elucidated.
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Affiliation(s)
- Hazizul Hussain-Yusuf
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
| | - John Stenos
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
| | - Gemma Vincent
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
| | - Amy Shima
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Townsville 4611, Queensland, Australia; (A.S.); (N.D.P.)
| | - Sandra Abell
- Centre for Tropical Biodiversity and Climate Change, James Cook University, Townsville 4611, Queensland, Australia; (S.A.); (N.B.); (K.M.)
| | - Noel D. Preece
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Townsville 4611, Queensland, Australia; (A.S.); (N.D.P.)
- Research Institute for Environment and Livelihoods, Charles Darwin University, Darwin 0815, Northern Territory, Australia
| | - Mythili Tadepalli
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
| | - Sze Fui Hii
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
| | - Naomi Bowie
- Centre for Tropical Biodiversity and Climate Change, James Cook University, Townsville 4611, Queensland, Australia; (S.A.); (N.B.); (K.M.)
| | - Kate Mitram
- Centre for Tropical Biodiversity and Climate Change, James Cook University, Townsville 4611, Queensland, Australia; (S.A.); (N.B.); (K.M.)
| | - Stephen Graves
- Australian Rickettsial Reference Laboratory, Geelong University Hospital, Geelong 3216, Victoria, Australia; (H.H.-Y.); (G.V.); (M.T.); (S.F.H.); (S.G.)
- Department of Microbiology and Infectious Diseases, Nepean Hospital, NSW Health Pathology, Penrith 2747, New South Wales, Australia
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Dehhaghi M, Kazemi Shariat Panahi H, Holmes EC, Hudson BJ, Schloeffel R, Guillemin GJ. Human Tick-Borne Diseases in Australia. Front Cell Infect Microbiol 2019; 9:3. [PMID: 30746341 PMCID: PMC6360175 DOI: 10.3389/fcimb.2019.00003] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/07/2019] [Indexed: 12/26/2022] Open
Abstract
There are 17 human-biting ticks known in Australia. The bites of Ixodes holocyclus, Ornithodoros capensis, and Ornithodoros gurneyi can cause paralysis, inflammation, and severe local and systemic reactions in humans, respectively. Six ticks, including Amblyomma triguttatum, Bothriocroton hydrosauri, Haemaphysalis novaeguineae, Ixodes cornuatus, Ixodes holocyclus, and Ixodes tasmani may transmit Coxiella burnetii, Rickettsia australis, Rickettsia honei, or Rickettsia honei subsp. marmionii. These bacterial pathogens cause Q fever, Queensland tick typhus (QTT), Flinders Island spotted fever (FISF), and Australian spotted fever (ASF). It is also believed that babesiosis can be transmitted by ticks to humans in Australia. In addition, Argas robertsi, Haemaphysalis bancrofti, Haemaphysalis longicornis, Ixodes hirsti, Rhipicephalus australis, and Rhipicephalus sanguineus ticks may play active roles in transmission of other pathogens that already exist or could potentially be introduced into Australia. These pathogens include Anaplasma spp., Bartonella spp., Burkholderia spp., Francisella spp., Dera Ghazi Khan virus (DGKV), tick-borne encephalitis virus (TBEV), Lake Clarendon virus (LCV), Saumarez Reef virus (SREV), Upolu virus (UPOV), or Vinegar Hill virus (VINHV). It is important to regularly update clinicians' knowledge about tick-borne infections because these bacteria and arboviruses are pathogens of humans that may cause fatal illness. An increase in the incidence of tick-borne infections of human may be observed in the future due to changes in demography, climate change, and increase in travel and shipments and even migratory patterns of birds or other animals. Moreover, the geographical conditions of Australia are favorable for many exotic ticks, which may become endemic to Australia given an opportunity. There are some human pathogens, such as Rickettsia conorii and Rickettsia rickettsii that are not currently present in Australia, but can be transmitted by some human-biting ticks found in Australia, such as Rhipicephalus sanguineus, if they enter and establish in this country. Despite these threats, our knowledge of Australian ticks and tick-borne diseases is in its infancy.
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Affiliation(s)
- Mona Dehhaghi
- Neuroinflammation Group, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Microbial Biotechnology, School of Biology and Centre of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran, Iran
| | - Hamed Kazemi Shariat Panahi
- Neuroinflammation Group, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Microbial Biotechnology, School of Biology and Centre of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran, Iran
| | - Edward C Holmes
- Charles Perkins Centre, School of Life and Environmental Sciences and Sydney Medical School, Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, NSW, Australia
| | - Bernard J Hudson
- Department of Microbiology and Infectious Disease, Royal North Shore Hospital, Sydney, NSW, Australia
| | | | - Gilles J Guillemin
- Neuroinflammation Group, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
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Irwin P, Egan S, Greay T, Oskam C. Bacterial tick-associated infections in Australia: current studies and future directions. MICROBIOLOGY AUSTRALIA 2018. [DOI: 10.1071/ma18063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
It may seem perplexing that there is any uncertainty in Australia about the existence of zoonotic tick-associated infections1–3. Outside this country, particularly in the northern hemisphere, tick-borne diseases such as human granulocytic anaplasmosis, babesiosis, Boutonneuse fever, ehrlichiosis, Lyme borreliosis, and tick-borne encephalitis, have well documented aetiologies, epidemiology, diagnostic methods, and treatments. Why is Australia different and what research is being conducted to address this issue? This article briefly addresses these questions and explains how high-throughput metagenomic analysis has started to shed light on bacterial microbiomes in Australian ticks, providing new data on the presence and distribution of potentially zoonotic microbial taxa.
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Moon KL, Chown SL, Loh SM, Oskam CL, Fraser CI. Australian penguin ticks screened for novel Borrelia species. Ticks Tick Borne Dis 2017; 9:410-414. [PMID: 29275874 DOI: 10.1016/j.ttbdis.2017.12.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/07/2017] [Accepted: 12/08/2017] [Indexed: 10/18/2022]
Abstract
Lyme borreliosis (or Lyme Disease) is an emerging threat to human health in the Northern Hemisphere caused by tick-borne bacteria from the Borrelia burgdorferi sensu lato (Bbsl) complex. Seabirds are important reservoir hosts of some members of the Bbsl complex in the Northern Hemisphere, and some evidence suggests this may be true of penguins in the Southern Hemisphere. While the Bbsl complex has not been detected in Australia, a novel Borrelia species ('Candidatus Borrelia tachyglossi') was recently sequenced from native ticks (Ixodes holocyclus and Bothriocroton concolor) parasitising echidnas (Tachyglossus aculeatus), suggesting unidentified borreliae may be circulating amongst native wildlife and their ticks. In the present study, we investigated whether ticks parasitising little penguins (Eudyptula novaehollandiae) harbour native or introduced Borrelia bacteria. We chose this penguin species because it is heavily exploited by ticks during the breeding season, lives in close proximity to other potential reservoir hosts (including native wildlife and migratory seabirds), and is known to be infected with other tick-borne pathogens (Babesia). We screened over 230 penguin ticks (Ixodes spp.) from colonies in south-eastern Australia, and found no evidence of Borrelia DNA. The apparent absence or rarity of the bacterium in south-eastern Australia has important implications for identifying potential tick-borne pathogens in an understudied region.
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Affiliation(s)
- Katherine L Moon
- Fenner School of Environment and Society, Australian National University, Acton, ACT 2601, Australia; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia.
| | - Steven L Chown
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Siew-May Loh
- Vector & Waterborne Pathogens Research Group, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Charlotte L Oskam
- Vector & Waterborne Pathogens Research Group, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Ceridwen I Fraser
- Fenner School of Environment and Society, Australian National University, Acton, ACT 2601, Australia
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Collignon PJ, Lum GD, Robson JM. Does Lyme disease exist in Australia? Med J Aust 2017; 205:413-417. [PMID: 27809728 DOI: 10.5694/mja16.00824] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 08/24/2016] [Indexed: 11/17/2022]
Abstract
There is no convincing evidence that classic Lyme disease occurs in Australia, nor is there evidence that the causative agent, Borrelia burgdorferi, is found in Australian animals or ticks. Lyme disease, however, can be acquired overseas but diagnosed in Australia; most people presenting with laboratory-confirmed Lyme disease in Australia were infected in Europe. Despite the lack of evidence that Lyme disease can be acquired in Australia, growing numbers of patients, their supporters, and some politicians demand diagnoses and treatment according to the protocols of the "chronic Lyme disease" school of thought. Antibiotic therapy for chronic "Lyme disease-like illness" can cause harm to both the individual (eg, cannula-related intravenous sepsis) and the broader community (increased antimicrobial resistance rates). Until there is strong evidence from well performed clinical studies that bacteria present in Australia cause a chronic debilitating illness that responds to prolonged antibiotics, treating patients with "Lyme disease-like illness" with prolonged antibiotic therapy is unjustified, and is likely to do much more harm than good.
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Affiliation(s)
| | - Gary D Lum
- ACT Pathology, Canberra Hospital, Canberra, ACT
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Chalada MJ, Stenos J, Bradbury RS. Is there a Lyme-like disease in Australia? Summary of the findings to date. One Health 2016; 2:42-54. [PMID: 28616477 PMCID: PMC5441348 DOI: 10.1016/j.onehlt.2016.03.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 03/19/2016] [Accepted: 03/19/2016] [Indexed: 01/06/2023] Open
Abstract
Lyme Borreliosis is a common tick-borne disease of the northern hemisphere caused by the spirochaetes of the Borrelia burgdorferi sensu lato (B. burgdorferi s. l.) complex. It results in multi-organ disease with arthritic, cardiac, neurological and dermatological manifestations. In the last twenty-five years there have been over 500 reports of an Australian Lyme-like syndrome in the scientific literature. However, the diagnoses of Lyme Borreliosis made in these cases have been primarily by clinical presentation and laboratory results of tentative reliability and the true cause of these illnesses remains unknown. A number of animals have been introduced to Australia that may act as B. burgdorferi s. l. reservoirs in Lyme-endemic countries, and there are some Australian Ixodes spp. and Haemaphysalis spp. ticks whose geographical distribution matches that of the Australian Lyme-like cases. Four published studies have searched for Borrelia in Australian ticks, with contradicting results. The cause of the potential Lyme-like disease in Australia remains to be defined. The evidence to date as to whether these illnesses are caused by a Borrelia species, another tick borne pathogen or are due to a novel or unrelated aetiology is summarised in this review.
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Affiliation(s)
- Melissa Judith Chalada
- School of Medical & Applied Sciences, Central Queensland University, Rockhampton, Queensland, Australia
| | - John Stenos
- Australian Rickettsial Reference Laboratory, Barwon Health, Geelong, Victoria, Australia
| | - Richard Stewart Bradbury
- School of Medical & Applied Sciences, Central Queensland University, Rockhampton, Queensland, Australia
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Loh SM, Gofton AW, Lo N, Gillett A, Ryan UM, Irwin PJ, Oskam CL. Novel Borrelia species detected in echidna ticks, Bothriocroton concolor, in Australia. Parasit Vectors 2016; 9:339. [PMID: 27301754 PMCID: PMC4908759 DOI: 10.1186/s13071-016-1627-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 06/07/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To date, little has been documented about microorganisms harboured within Australian native ticks or their pathogenic potential. Recently, a Borrelia sp. related to the Relapsing Fever (RF) group was identified in a single tick removed from a wild echidna (Tachyglossus aculeatus). The present study investigated the presence of Borrelia in 97 Bothriocroton concolor ticks parasitizing echidnas in Queensland, New South Wales, and Victoria, Australia, using nested PCR with Borrelia-specific primers targeting the 16S rRNA (16S) and flaB genes. RESULTS Borrelia-specific PCR assays confirmed the presence of a novel Borrelia sp. related to the RF and reptile-associated (REP) spirochaetes in 38 (39 %) B. concolor ticks. This novel Borrelia sp. was identified in 41 % of the B. concolor ticks in Queensland and New South Wales, but not in any ticks from Victoria. The resulting flaB sequences (407 bp) were 88 and 86 % similar to the flaB sequences from Borrelia turcica and Borrelia hermsii, respectively. Of the ticks confirmed as Borrelia-positive following the flaB assay, 28 were positive with the 16S assay. Phylogenetic analysis of the 16S sequences (1097 bp) suggests that these sequences belong to a novel Borrelia sp., which forms a unique monophyletic clade that is similar to, but distinct from, RF Borrelia spp. and REP-associated Borrelia spp. CONCLUSIONS We conclude that the novel Borrelia sp. identified in this study does not belong to the Borrelia burgdorferi (sensu lato) complex, and that the phylogenetic analysis of the partial 16S gene sequences suggests it forms a unique monophyletic cluster in the genus Borrelia, potentially forming a fourth major group in this genus associated with monotremes in Australia. However, a thorough molecular characterisation will be required to confirm the phylogenetic position of this unique Borrelia sp. The zoonotic potential and pathogenic consequences of this novel Borrelia sp. are unknown at the current time.
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Affiliation(s)
- Siew-May Loh
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Alexander W Gofton
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Nathan Lo
- School of Biological Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Amber Gillett
- Australia Zoo Wildlife Hospital, Beerwah, Queensland, Australia
| | - Una M Ryan
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Peter J Irwin
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Charlotte L Oskam
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
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Gofton AW, Doggett S, Ratchford A, Oskam CL, Paparini A, Ryan U, Irwin P. Bacterial Profiling Reveals Novel "Ca. Neoehrlichia", Ehrlichia, and Anaplasma Species in Australian Human-Biting Ticks. PLoS One 2015; 10:e0145449. [PMID: 26709826 PMCID: PMC4692421 DOI: 10.1371/journal.pone.0145449] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 12/03/2015] [Indexed: 12/19/2022] Open
Abstract
In Australia, a conclusive aetiology of Lyme disease-like illness in human patients remains elusive, despite growing numbers of people presenting with symptoms attributed to tick bites. In the present study, we surveyed the microbial communities harboured by human-biting ticks from across Australia to identify bacteria that may contribute to this syndrome. Universal PCR primers were used to amplify the V1-2 hyper-variable region of bacterial 16S rRNA genes in DNA samples from individual Ixodes holocyclus (n = 279), Amblyomma triguttatum (n = 167), Haemaphysalis bancrofti (n = 7), and H. longicornis (n = 7) ticks. The 16S amplicons were sequenced on the Illumina MiSeq platform and analysed in USEARCH, QIIME, and BLAST to assign genus and species-level taxonomies. Nested PCR and Sanger sequencing were used to confirm the NGS data and further analyse novel findings. All 460 ticks were negative for Borrelia spp. by both NGS and nested PCR analysis. Two novel "Candidatus Neoehrlichia" spp. were identified in 12.9% of I. holocyclus ticks. A novel Anaplasma sp. was identified in 1.8% of A. triguttatum ticks, and a novel Ehrlichia sp. was identified in both A. triguttatum (1.2%) ticks and a single I. holocyclus (0.6%) tick. Further phylogenetic analysis of novel "Ca. Neoehrlichia", Anaplasma and Ehrlichia based on 1,265 bp 16S rRNA gene sequences suggests that these are new species. Determining whether these newly discovered organisms cause disease in humans and animals, like closely related bacteria do abroad, is of public health importance and requires further investigation.
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Affiliation(s)
- Alexander W. Gofton
- Vector and Water-borne Pathogen Research Group, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Stephen Doggett
- Department of Medical Entomology, Pathology West and Institute for Clinical Pathology and Medical Research, Westmead Hospital, Westmead, New South Wales, Australia
| | - Andrew Ratchford
- Emergency Department, Mona Vale Hospital, New South Wales, Australia
| | - Charlotte L. Oskam
- Vector and Water-borne Pathogen Research Group, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Andrea Paparini
- Vector and Water-borne Pathogen Research Group, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Una Ryan
- Vector and Water-borne Pathogen Research Group, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Peter Irwin
- Vector and Water-borne Pathogen Research Group, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
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Gofton AW, Oskam CL, Lo N, Beninati T, Wei H, McCarl V, Murray DC, Paparini A, Greay TL, Holmes AJ, Bunce M, Ryan U, Irwin P. Inhibition of the endosymbiont "Candidatus Midichloria mitochondrii" during 16S rRNA gene profiling reveals potential pathogens in Ixodes ticks from Australia. Parasit Vectors 2015; 8:345. [PMID: 26108374 PMCID: PMC4493822 DOI: 10.1186/s13071-015-0958-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 06/17/2015] [Indexed: 02/01/2023] Open
Abstract
Background The Australian paralysis tick (Ixodes holocyclus) is of significant medical and veterinary importance as a cause of dermatological and neurological disease, yet there is currently limited information about the bacterial communities harboured by these ticks and the risk of infectious disease transmission to humans and domestic animals. Ongoing controversy about the presence of Borrelia burgdorferi sensu lato (the aetiological agent of Lyme disease) in Australia increases the need to accurately identify and characterise bacteria harboured by I. holocyclus ticks. Methods Universal PCR primers were used to amplify the V1-2 hyper-variable region of bacterial 16S rRNA genes present in DNA samples from I. holocyclus and I. ricinus ticks, collected in Australia and Germany respectively. The 16S amplicons were purified, sequenced on the Ion Torrent platform, and analysed in USEARCH, QIIME, and BLAST to assign genus and species-level taxonomy. Initial analysis of I. holocyclus and I. ricinus identified that > 95 % of the 16S sequences recovered belonged to the tick intracellular endosymbiont “Candidatus Midichloria mitochondrii” (CMM). A CMM-specific blocking primer was designed that decreased CMM sequences by approximately 96 % in both tick species and significantly increased the total detectable bacterial diversity, allowing identification of medically important bacterial pathogens that were previously masked by CMM. Results Borrelia burgdorferi sensu lato was identified in German I. ricinus, but not in Australian I. holocyclus ticks. However, bacteria of medical significance were detected in I. holocyclus ticks, including a Borrelia relapsing fever group sp., Bartonella henselae, novel “Candidatus Neoehrlichia” spp., Clostridium histolyticum, Rickettsia spp., and Leptospira inadai. Conclusions Abundant bacterial endosymbionts, such as CMM, limit the effectiveness of next-generation 16S bacterial community profiling in arthropods by masking less abundant bacteria, including pathogens. Specific blocking primers that inhibit endosymbiont 16S amplification during PCR are an effective way of reducing this limitation. Here, this strategy provided the first evidence of a relapsing fever Borrelia sp. and of novel “Candidatus Neoehrlichia” spp. in Australia. Our results raise new questions about tick-borne pathogens in I. holocyclus ticks. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-0958-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexander W Gofton
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Charlotte L Oskam
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Nathan Lo
- School of Biological Sciences, The University of Sydney, Sydney, New South Wales, Australia.
| | - Tiziana Beninati
- Faculty of Veterinary Science, The University of Sydney, Sydney, New South Wales, Australia.
| | - Heng Wei
- School of Biological Sciences, The University of Sydney, Sydney, New South Wales, Australia.
| | - Victoria McCarl
- School of Biological Sciences, The University of Sydney, Sydney, New South Wales, Australia.
| | - Dáithí C Murray
- Trace and Environmental DNA Laboratory, Department of Environment and Agriculture, Curtin University, Perth, Western Australia, Australia.
| | - Andrea Paparini
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Telleasha L Greay
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Andrew J Holmes
- School of Molecular Biosciences and Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia.
| | - Michael Bunce
- Trace and Environmental DNA Laboratory, Department of Environment and Agriculture, Curtin University, Perth, Western Australia, Australia.
| | - Una Ryan
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Peter Irwin
- Vector and Water-Borne Pathogen Research Laboratory, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
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Russell RC, Doggett SL, Munro R, Ellis J, Avery D, Hunt C, Dickeson D. Lyme disease: a search for a causative agent in ticks in south-eastern Australia. Epidemiol Infect 1994; 112:375-84. [PMID: 8150011 PMCID: PMC2271457 DOI: 10.1017/s0950268800057782] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Attempts were made to identify the causative organism of Lyme disease in Australia from possible tick vectors. Ticks were collected in coastal areas of New South Wales, Australia, from localities associated with putative human infections. The ticks were dissected; a portion of the gut contents was examined for spirochaetes by microscopy, the remaining portion inoculated into culture media. The detection of spirochaetes in culture was performed using microscopy, and immunochemical and molecular (PCR) techniques. Additionally, whole ticks were tested with PCR for spirochaetes. From 1990 to 1992, approximately 12,000 ticks were processed for spirochaetes. No evidence of Borrelia burgdorferi or any other spirochaete was recovered from or detected in likely tick vectors. Some spirochaete-like objects detected in the cultures were shown to be artifacts, probably aggregates of bacterial flagellae. There is no definitive evidence for the existence in Australia of B. burgdorferi the causative agent of true Lyme disease, or for any other tick-borne spirochaete that may be responsible for a local syndrome being reported as Lyme disease.
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Affiliation(s)
- R C Russell
- Department of Medical Entomology, University of Sydney and Westmead Hospital, ICPMR, Westmead Hospital, NSW, Australia
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