1
|
Abdelrahim NA, Fadl-Elmula IM, Hartskeerl RA, Ahmed A, Goris M. Are Pathogenic Leptospira a Possible Cause of Aseptic Meningitis in Suspected Children in Sudan? Res Rep Trop Med 2021; 12:267-274. [PMID: 35002355 PMCID: PMC8725262 DOI: 10.2147/rrtm.s339058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/07/2021] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Clinical presentations of leptospirosis are diverse, with meningitis easily confused with other microbial causes. We aimed to investigate the involvement of pathogenic leptospira in the cerebrospinal fluid (CSF) of meningitis-suspected children in Sudan. METHODS A total of 153 CSF specimens were collected over 5 months from patients attending a reference pediatric hospital in Omdurman, Sudan. All patients had provisionally been diagnosed with meningitis on admission. Demographic, clinical, and conventional laboratory findings were obtained. DNA was extracted using a QIAamp mini kit, and the secY gene investigated using real-time PCR. RESULTS Nine of 153 (6%) CSF specimens were positive for pathogenic leptospiral DNA. All these patients were male (seven infants and two toddlers aged ˂4 years). Typical conventional laboratory findings for aseptic meningitis (ie, CSF turbidity/pleocytosis, normal or reduced CSF glucose, normal or elevated proteins) were seen in five (56%). All patients presented with fever and seizures, 56% vomiting and stiff neck, and 29% bulging fontanel. Most (67%) patients presented in summer (March to May). Polymicrobial infections were identified in three patients (33%). CONCLUSION We conclude that pathogenic leptospira are probably a common cause of meningitis in children in Sudan; therefore, we recommend including leptospirosis in the differential diagnosis of CNS infections and other undifferentiated febrile illnesses in this country.
Collapse
Affiliation(s)
- Nada Abdelghani Abdelrahim
- Department of Medical Microbiology, Faculty of Medical Laboratory Sciences, Nile University, Khartoum, Sudan
| | - Imad Mohammed Fadl-Elmula
- Department of Pathology & Clinical Genetics, Al-Neelain University and Assafa Academy, Khartoum, Sudan
| | - Rudy A Hartskeerl
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Medical Microbiology, Academic Medical Center, Amsterdam, Netherlands
| | - Ahmed Ahmed
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Medical Microbiology, Academic Medical Center, Amsterdam, Netherlands
| | - Marga Goris
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Medical Microbiology, Academic Medical Center, Amsterdam, Netherlands
| |
Collapse
|
2
|
Ferreira AS, Ahmed A, Rocha T, Vieira ML, Paiva-Cardoso MDN, Mesquita JR, van der Linden H, Goris M, Thompson G, Hartskeerl RA, Inácio J. Genetic diversity of pathogenic leptospires from wild, domestic and captive host species in Portugal. Transbound Emerg Dis 2019; 67:852-864. [PMID: 31677243 DOI: 10.1111/tbed.13409] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/17/2019] [Accepted: 10/21/2019] [Indexed: 12/22/2022]
Abstract
Leptospirosis is a neglected zoonotic disease of worldwide distribution with a significant veterinary and public health impact. It is caused by pathogenic bacteria of the genus Leptospira. The availability of effective tools to accurately identify and type leptospires is of utmost importance for the diagnosis of the disease and for assessing its epidemiology. Several multi-locus sequence typing (MLST) approaches were described for the typing of worldwide isolates of Leptospira but an extensive agreement towards the adoption of a unique consensus scheme for this agent is still lacking. Most genotyped strains originate from Asian and South American countries, with a minority originating from Europe (being most countries represented only by one or a few isolates). The knowledge of the diversity of circulating leptospires is the key to understanding the disease transmission and its zoonotic implications. In this study, we revisited the taxonomy of several isolates of pathogenic Leptospira obtained from domestic, wild and captive animals in Portugal, between 1990 and 2012. A selection of these isolates was genotyped using two previously published MLST schemes. A total of seven distinct sequence types (STs) were detected among the Portuguese isolates with two STs representing L. borgpetersenii (ST149 and ST152), two STs representing L. kirschneri (ST117 and ST100) and three STs representing L. interrogans (ST17, ST24 and ST140). Global widespread (and maybe more virulent) Leptospira genotypes seem to circulate in Portugal, particularly the L. interrogans ST17 isolates which are associated with several outbreaks of leptospirosis among humans and animals in different regions of the world. This study contributes to the enrichment of the global MLST databases with a new set of allele and sequence type information also providing novel data on circulating Leptospira serovars in Portugal.
Collapse
Affiliation(s)
- Ana S Ferreira
- Laboratory of Microbiology, Department of Biological Sciences, Faculty of Pharmacy, University of Oporto, Porto, Portugal
| | - Ahmed Ahmed
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Academic Medical Center, Department of Medical Microbiology, University of Amsterdam, Amsterdam, The Netherlands
| | - Teresa Rocha
- Instituto Nacional de Investigação Agrária e Veterinária, Unidade Estratégica de Produção e Saúde Animal, Oeiras, Portugal
| | - Maria L Vieira
- Unidade de Microbiologia Médica, Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisboa, Portugal
| | - Maria das Neves Paiva-Cardoso
- Department of Veterinary Sciences, Centre for the Research and Technology of Agro-Environment and Biological Sciences (CITAB)/Animal and Veterinary Research Centre (CECAV), Universidade de Trás-os-Montes e Alto Douro (UTAD), Vila Real, Portugal
| | - João R Mesquita
- Epidemiology Research Unit (EPIUnit), Instituto de Saúde Pública da Universidade do Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar, University of Porto, Porto, Portugal
| | - Hans van der Linden
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Academic Medical Center, Department of Medical Microbiology, University of Amsterdam, Amsterdam, The Netherlands
| | - Marga Goris
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Academic Medical Center, Department of Medical Microbiology, University of Amsterdam, Amsterdam, The Netherlands
| | - Gertrude Thompson
- Epidemiology Research Unit (EPIUnit), Instituto de Saúde Pública da Universidade do Porto, Porto, Portugal.,Research Center in Biodiversity and Genetic Resources, University of Porto, Vila do Conde, Portugal
| | - Rudy A Hartskeerl
- OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Academic Medical Center, Department of Medical Microbiology, University of Amsterdam, Amsterdam, The Netherlands
| | - João Inácio
- Unidade de Microbiologia Médica, Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisboa, Portugal.,School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
| |
Collapse
|
3
|
Yang B, de Vries SG, Ahmed A, Visser BJ, Nagel IM, Spijker R, Grobusch MP, Hartskeerl RA, Goris MGA, Leeflang MMG. Nucleic acid and antigen detection tests for leptospirosis. Cochrane Database Syst Rev 2019; 8:CD011871. [PMID: 31425612 PMCID: PMC6699653 DOI: 10.1002/14651858.cd011871.pub2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Early diagnosis of leptospirosis may contribute to the effectiveness of antimicrobial therapy and early outbreak recognition. Nucleic acid and antigen detection tests have the potential for early diagnosis of leptospirosis. With this systematic review, we assessed the sensitivity and specificity of nucleic acid and antigen detection tests. OBJECTIVES To determine the diagnostic test accuracy of nucleic acid and antigen detection tests for the diagnosis of human symptomatic leptospirosis. SEARCH METHODS We searched electronic databases including MEDLINE, Embase, the Cochrane Library, and regional databases from inception to 6 July 2018. We did not apply restrictions to language or time of publication. SELECTION CRITERIA We included diagnostic cross-sectional studies and case-control studies of tests that made use of nucleic acid and antigen detection methods in people suspected of systemic leptospirosis. As reference standards, we considered the microscopic agglutination test alone (which detects antibodies against leptospirosis) or in a composite reference standard with culturing or other serological tests. Studies were excluded when the controls were healthy individuals or when there were insufficient data to calculate sensitivity and specificity. DATA COLLECTION AND ANALYSIS At least two review authors independently extracted data from each study. We used the revised Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2) to assess risk of bias. We calculated study-specific values for sensitivity and specificity with 95% confidence intervals (CI) and pooled the results in a meta-analysis when appropriate. We used the bivariate model for index tests with one positivity threshold, and we used the hierarchical summary receiver operating characteristic model for index tests with multiple positivity thresholds. As possible sources of heterogeneity, we explored: timing of index test, disease prevalence, blood sample type, primers or target genes, and the real-time polymerase chain reaction (PCR) visualisation method. These were added as covariates to the meta-regression models. MAIN RESULTS We included 41 studies evaluating nine index tests (conventional PCR (in short: PCR), real-time PCR, nested PCR, PCR performed twice, loop-mediated isothermal amplification, enzyme-linked immunosorbent assay (ELISA), dot-ELISA, immunochromatography-based lateral flow assay, and dipstick assay) with 5981 participants (1834 with and 4147 without leptospirosis). Methodological quality criteria were often not reported, and the risk of bias of the reference standard was generally considered high. The applicability of findings was limited by the frequent use of frozen samples. We conducted meta-analyses for the PCR and the real-time PCR on blood products.The pooled sensitivity of the PCR was 70% (95% CI 37% to 90%) and the pooled specificity was 95% (95% CI 75% to 99%). When studies with a high risk of bias in the reference standard domain were excluded, the pooled sensitivity was 87% (95% CI 44% to 98%) and the pooled specificity was 97% (95% CI 60% to 100%). For the real-time PCR, we estimated a summary receiver operating characteristic curve. To illustrate, a point on the curve with 85% specificity had a sensitivity of 49% (95% CI 30% to 68%). Likewise, at 90% specificity, sensitivity was 40% (95% CI 24% to 59%) and at 95% specificity, sensitivity was 29% (95% CI 15% to 49%). The median specificity of real-time PCR on blood products was 92%. We did not formally compare the diagnostic test accuracy of PCR and real-time PCR, as direct comparison studies were lacking. Three of 15 studies analysing PCR on blood products reported the timing of sample collection in the studies included in the meta-analyses (range 1 to 7 days postonset of symptoms), and nine out of 16 studies analysing real-time PCR on blood products (range 1 to 19 days postonset of symptoms). In PCR studies, specificity was lower in settings with high leptospirosis prevalence. Other investigations of heterogeneity did not identify statistically significant associations. Two studies suggested that PCR and real-time PCR may be more sensitive on blood samples collected early in the disease stage. Results of other index tests were described narratively. AUTHORS' CONCLUSIONS The validity of review findings are limited and should be interpreted with caution. There is a substantial between-study variability in the accuracy of PCR and real-time PCR, as well as a substantial variability in the prevalence of leptospirosis. Consequently, the position of PCR and real-time PCR in the clinical pathway depends on regional considerations such as disease prevalence, factors that are likely to influence accuracy, and downstream consequences of test results. There is insufficient evidence to conclude which of the nucleic acid and antigen detection tests is the most accurate. There is preliminary evidence that PCR and real-time PCR are more sensitive on blood samples collected early in the disease stage, but this needs to be confirmed in future studies.
Collapse
Affiliation(s)
- Bada Yang
- Amsterdam University Medical Centers, University of AmsterdamDepartment of Clinical Epidemiology, Biostatistics and BioinformaticsMeibergdreef 9AmsterdamNoord‐HollandNetherlands1105 AZ
| | - Sophia G de Vries
- Amsterdam University Medical Centers, location AMC, University of AmsterdamCenter of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal MedicineMeibergdreef 9AmsterdamNoord‐HollandNetherlands1105 AZ
| | - Ahmed Ahmed
- Academic Medical Centre (AMC), University of AmsterdamMedical Microbiology, OIE and National Collaborating Centre for Reference and Research on LeptospirosisMeibergdreef 39AmsterdamNetherlands1105 AZ
| | - Benjamin J Visser
- Amsterdam University Medical Centers, location AMC, University of AmsterdamCenter of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal MedicineMeibergdreef 9AmsterdamNoord‐HollandNetherlands1105 AZ
| | - Ingeborg M Nagel
- Amsterdam UMC, University of AmsterdamMedical LibraryMeibergdreef 9AmsterdamNetherlands1105 AZ
| | - René Spijker
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht UniversityCochrane NetherlandsRoom Str. 6.127P.O. Box 85500UtrechtNetherlands3508 GA
- Amsterdam UMC, University of Amsterdam, Amsterdam Public HealthMedical LibraryMeibergdreef 9AmsterdamNetherlands
| | - Martin P Grobusch
- Amsterdam University Medical Centers, location AMC, University of AmsterdamCenter of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal MedicineMeibergdreef 9AmsterdamNoord‐HollandNetherlands1105 AZ
| | - Rudy A Hartskeerl
- OIE and National Collaborating Centre for Reference and Research on LeptospirosisMeibergdreef 39AmsterdamNetherlands1105 AZ
| | - Marga GA Goris
- Academic Medical Centre (AMC), University of AmsterdamMedical Microbiology, OIE and National Collaborating Centre for Reference and Research on LeptospirosisMeibergdreef 39AmsterdamNetherlands1105 AZ
| | - Mariska MG Leeflang
- Amsterdam University Medical Centers, University of AmsterdamDepartment of Clinical Epidemiology, Biostatistics and BioinformaticsMeibergdreef 9AmsterdamNoord‐HollandNetherlands1105 AZ
| | | |
Collapse
|
4
|
Santos LA, Adhikarla H, Yan X, Wang Z, Fouts DE, Vinetz JM, Alcantara LCJ, Hartskeerl RA, Goris MGA, Picardeau M, Reis MG, Townsend JP, Zhao H, Ko AI, Wunder EA. Genomic Comparison Among Global Isolates of L. interrogans Serovars Copenhageni and Icterohaemorrhagiae Identified Natural Genetic Variation Caused by an Indel. Front Cell Infect Microbiol 2018; 8:193. [PMID: 29971217 PMCID: PMC6018220 DOI: 10.3389/fcimb.2018.00193] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/22/2018] [Indexed: 12/30/2022] Open
Abstract
Leptospirosis is a worldwide zoonosis, responsible for more than 1 million cases and 60,000 deaths every year. Among the 13 pathogenic species of the genus Leptospira, serovars belonging to L. interrogans serogroup Icterohaemorrhagiae are considered to be the most virulent strains, and responsible for majority of the reported severe cases. Serovars Copenhageni and Icterohaemorrhagiae are major representatives of this serogroup and despite their public health relevance, little is known regarding the genetic differences between these two serovars. In this study, we analyzed the genome sequences of 67 isolates belonging to L. interrogans serovars Copenhageni and Icterohaemorrhagiae to investigate the influence of spatial and temporal variations on DNA sequence diversity. Out of the 1072 SNPs identified, 276 were in non-coding regions and 796 in coding regions. Indel analyses identified 258 indels, out of which 191 were found in coding regions and 67 in non-coding regions. Our phylogenetic analyses based on SNP dataset revealed that both serovars are closely related but showed distinct spatial clustering. However, likelihood ratio test of the indel data statistically confirmed the presence of a frameshift mutation within a homopolymeric tract of lic12008 gene (related to LPS biosynthesis) in all the L. interrogans serovar Icterohaemorrhagiae strains but not in the Copenhageni strains. Therefore, this internal indel identified can genetically distinguish L. interrogans serovar Copenhageni from serovar Icterohaemorrhagiae with high discriminatory power. To our knowledge, this is the first study to identify global sequence variations (SNPs and Indels) in L. interrogans serovars Copenhageni and Icterohaemorrhagiae.
Collapse
Affiliation(s)
- Luciane A Santos
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Haritha Adhikarla
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States
| | - Xiting Yan
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Zheng Wang
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | | | - Joseph M Vinetz
- Division of Infectious Diseases, Department of Medicine, University of California San Diego School of Medicine, La Jolla, CA, United States
| | | | - Rudy A Hartskeerl
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | - Marga G A Goris
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | | | | | - Jeffrey P Townsend
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Hongyu Zhao
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Albert I Ko
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Elsio A Wunder
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| |
Collapse
|
5
|
Allan KJ, Halliday JEB, Moseley M, Carter RW, Ahmed A, Goris MGA, Hartskeerl RA, Keyyu J, Kibona T, Maro VP, Maze MJ, Mmbaga BT, Tarimo R, Crump JA, Cleaveland S. Assessment of animal hosts of pathogenic Leptospira in northern Tanzania. PLoS Negl Trop Dis 2018; 12:e0006444. [PMID: 29879104 PMCID: PMC5991636 DOI: 10.1371/journal.pntd.0006444] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 04/11/2018] [Indexed: 12/29/2022] Open
Abstract
Leptospirosis is a zoonotic bacterial disease that affects more than one million people worldwide each year. Human infection is acquired through direct or indirect contact with the urine of an infected animal. A wide range of animals including rodents and livestock may shed Leptospira bacteria and act as a source of infection for people. In the Kilimanjaro Region of northern Tanzania, leptospirosis is an important cause of acute febrile illness, yet relatively little is known about animal hosts of Leptospira infection in this area. The roles of rodents and ruminant livestock in the epidemiology of leptospirosis were evaluated through two linked studies. A cross-sectional study of peri-domestic rodents performed in two districts with a high reported incidence of human leptospirosis found no evidence of Leptospira infection among rodent species trapped in and around randomly selected households. In contrast, pathogenic Leptospira infection was detected in 7.08% cattle (n = 452 [5.1-9.8%]), 1.20% goats (n = 167 [0.3-4.3%]) and 1.12% sheep (n = 89 [0.1-60.0%]) sampled in local slaughterhouses. Four Leptospira genotypes were detected in livestock. Two distinct clades of L. borgpetersenii were identified in cattle as well as a clade of novel secY sequences that showed only 95% identity to known Leptospira sequences. Identical L. kirschneri sequences were obtained from qPCR-positive kidney samples from cattle, sheep and goats. These results indicate that ruminant livestock are important hosts of Leptospira in northern Tanzania. Infected livestock may act as a source of Leptospira infection for people. Additional work is needed to understand the role of livestock in the maintenance and transmission of Leptospira infection in this region and to examine linkages between human and livestock infections.
Collapse
Affiliation(s)
- Kathryn J. Allan
- The Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Jo E. B. Halliday
- The Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Mark Moseley
- Institute of Biological and Environmental Science, University of Aberdeen, Aberdeen, United Kingdom
| | - Ryan W. Carter
- The Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Ahmed Ahmed
- WHO/FAO/OIE Collaborating Leptospirosis Reference Laboratory, Royal Tropical Institute, Amsterdam, The Netherlands
| | - Marga G. A. Goris
- WHO/FAO/OIE Collaborating Leptospirosis Reference Laboratory, Royal Tropical Institute, Amsterdam, The Netherlands
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE Collaborating Leptospirosis Reference Laboratory, Royal Tropical Institute, Amsterdam, The Netherlands
| | - Julius Keyyu
- Tanzania Wildlife Research Institute, Arusha, Tanzania
| | - Tito Kibona
- Nelson Mandela African Institution for Science and Technology, Arusha, Tanzania
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Venance P. Maro
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Michael J. Maze
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Blandina T. Mmbaga
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Rigobert Tarimo
- Nelson Mandela African Institution for Science and Technology, Arusha, Tanzania
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - John A. Crump
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
- Centre for International Health, University of Otago, Dunedin, New Zealand
- Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
| | - Sarah Cleaveland
- The Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- Nelson Mandela African Institution for Science and Technology, Arusha, Tanzania
| |
Collapse
|
6
|
Rood EJJ, Goris MGA, Pijnacker R, Bakker MI, Hartskeerl RA. Environmental risk of leptospirosis infections in the Netherlands: Spatial modelling of environmental risk factors of leptospirosis in the Netherlands. PLoS One 2017; 12:e0186987. [PMID: 29065186 PMCID: PMC5655435 DOI: 10.1371/journal.pone.0186987] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/11/2017] [Indexed: 12/29/2022] Open
Abstract
Leptospirosis is a globally emerging zoonotic disease, associated with various climatic, biotic and abiotic factors. Mapping and quantifying geographical variations in the occurrence of leptospirosis and the surrounding environment offer innovative methods to study disease transmission and to identify associations between the disease and the environment. This study aims to investigate geographic variations in leptospirosis incidence in the Netherlands and to identify associations with environmental factors driving the emergence of the disease. Individual case data derived over the period 1995–2012 in the Netherlands were geocoded and aggregated by municipality. Environmental covariate data were extracted for each municipality and stored in a spatial database. Spatial clusters were identified using kernel density estimations and quantified using local autocorrelation statistics. Associations between the incidence of leptospirosis and the local environment were determined using Simultaneous Autoregressive Models (SAR) explicitly modelling spatial dependence of the model residuals. Leptospirosis incidence rates were found to be spatially clustered, showing a marked spatial pattern. Fitting a spatial autoregressive model significantly improved model fit and revealed significant association between leptospirosis and the coverage of arable land, built up area, grassland and sabulous clay soils. The incidence of leptospirosis in the Netherlands could effectively be modelled using a combination of soil and land-use variables accounting for spatial dependence of incidence rates per municipality. The resulting spatially explicit risk predictions provide an important source of information which will benefit clinical awareness on potential leptospirosis infections in endemic areas.
Collapse
Affiliation(s)
- Ente J. J. Rood
- KIT Royal Tropical Institute, Health dept., Amsterdam, The Netherlands
- * E-mail:
| | - Marga G. A. Goris
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Amsterdam, The Netherlands
| | - Roan Pijnacker
- KIT Royal Tropical Institute, Health dept., Amsterdam, The Netherlands
| | - Mirjam I. Bakker
- KIT Royal Tropical Institute, Health dept., Amsterdam, The Netherlands
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Amsterdam, The Netherlands
| |
Collapse
|
7
|
Denipitiya DTH, Chandrasekharan NV, Abeyewickreme W, Hartskeerl RA, Hapugoda MD. Identification of cattle, buffaloes and rodents as reservoir animals of Leptospira in the District of Gampaha, Sri Lanka. BMC Res Notes 2017; 10:134. [PMID: 28330498 PMCID: PMC5363019 DOI: 10.1186/s13104-017-2457-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Accepted: 03/17/2017] [Indexed: 11/17/2022] Open
Abstract
Background Leptospirosis is an important emerging infectious disease in Sri Lanka. Rats are the most important reservoir of Leptospira but domestic and wild mammals may also act as important maintenance or accidental hosts. In Sri Lanka, knowledge of reservoir animals of leptospires is poor. The objective of this study was to identify potential reservoir animals of Leptospira in the District of Gampaha, Sri Lanka. Findings Blood and kidney samples were collected from 38 rodents and mid-stream urine samples were randomly collected from 45 cattle and five buffaloes in the District of Gampaha. Kidney and urine samples were tested by real-time polymerase chain reaction (PCR) and serum samples were tested by the microscopic agglutination test (MAT). Of the 38 rodent kidney samples, 11% (4/38) were positive by real-time PCR. The prevalence of leptospiral carriage was 11% (3/26) and 8% (1/12) in female and male rodents, respectively. Three rodent serum samples were positive by MAT. Of the 50 cattle/buffalo urine samples tested, 10% (5/50) were positive by real-time PCR. The prevalence of leptospiral carriage was 9% (4/45) and 20% (1/5) in cattle and buffaloes, respectively. Conclusion Results of PCR and MAT showed that Leptospira were present in a significant proportion of the rodents and farm animals tested in this study and suggest that these (semi-) domestic animals form an infection reservoir for Leptospira. Therefore, there is a potential zoonotic risk to public health, most notably to farmers in this area.
Collapse
Affiliation(s)
- D T H Denipitiya
- Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, P.O. Box 06, Ragama, Sri Lanka.,Department of Chemistry, Faculty of Science, University of Colombo, Colombo 03, Sri Lanka
| | - N V Chandrasekharan
- Department of Chemistry, Faculty of Science, University of Colombo, Colombo 03, Sri Lanka
| | - W Abeyewickreme
- Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, P.O. Box 06, Ragama, Sri Lanka
| | - R A Hartskeerl
- WHO/FAO/OIE Collaborating Centre on Leptospirosis, KIT Biomedical Research, Meibergdreef 39, Amsterdam, Netherlands
| | - M D Hapugoda
- Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, P.O. Box 06, Ragama, Sri Lanka.
| |
Collapse
|
8
|
Pijnacker R, Goris MGA, Te Wierik MJM, Broens EM, van der Giessen JWB, de Rosa M, Wagenaar JA, Hartskeerl RA, Notermans DW, Maassen K, Schimmer B. Marked increase in leptospirosis infections in humans and dogs in the Netherlands, 2014. ACTA ACUST UNITED AC 2017; 21:30211. [PMID: 27168584 DOI: 10.2807/1560-7917.es.2016.21.17.30211] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 11/10/2015] [Indexed: 01/13/2023]
Abstract
In the Netherlands, 97 human leptospirosis cases were notified in 2014. This represents a 4.6-fold increase in autochthonous cases (n = 60) compared with the annual average between 2010 and 2013. Most cases had symptom onset between June and November. This marked increase in humans coincided with an increase of leptospirosis in dogs. In 2014, 13 dogs with leptospirosis were reported, compared with two to six dogs annually from 2010 to 2013. The majority of the autochthonous cases (n = 20) were linked to recreational exposure, e.g. swimming or fishing, followed by occupational exposure (n = 15). About sixty per cent (n = 37) of the autochthonous cases were most likely attributable to surface water contact, and 13 cases to direct contact with animals, mainly rats. A possible explanation for this increase is the preceding mild winter of 2013-2014 followed by the warmest year in three centuries, possibly enabling rodents and Leptospira spp. to survive better. A slight increase in imported leptospirosis was also observed in Dutch tourists (n = 33) most of whom acquired their infection in Thailand (n = 18). More awareness and early recognition of this mainly rodent-borne zoonosis by medical and veterinary specialists is warranted.
Collapse
Affiliation(s)
- Roan Pijnacker
- Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Benacer D, Thong KL, Min NC, Bin Verasahib K, Galloway RL, Hartskeerl RA, Souris M, Mohd Zain SN. Epidemiology of human leptospirosis in Malaysia, 2004-2012. Acta Trop 2016; 157:162-8. [PMID: 26844370 DOI: 10.1016/j.actatropica.2016.01.031] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/28/2016] [Accepted: 01/29/2016] [Indexed: 01/05/2023]
Abstract
Leptospirosis is an emerging disease, especially in countries with a tropical climate such as Malaysia. A dramatic increase in the number of cases has been reported over the last decade; however, information on the epidemiological trends of this disease is lacking. The objective of this study is to provide an epidemiological description of human leptospirosis cases over a 9-year period (2004-2012) and disease relationship with meteorological, geographical, and demographical information. A retrospective study was undertaken to describe the patterns of human leptospirosis cases and their association with intrinsic (sex, age, and ethnicity) and extrinsic (location, rainfall, and temperature) factors. Data was grouped according to age, sex, ethnicity, seasonality and geographical distribution, and analyzed using statistical tools to understand the influence of all the different factors on disease incidence. A total of 12,325 cases of leptospirosis were reported between 2004 and 2012 with an upward trend in disease incidence, with the highest in 2012. Three hundred thirty-eight deaths were reported with an overall case fatality rate of 2.74%, with higher incidence in males (9696; 78.7%) compared with female patients (2629; 21.3%), and overall male to female ratio of 3.69:1. Patients aged cohorts between 30-39 years old (16.22 per 100,000 population) had the highest disease incidence while the lowest incidence occurred between <1 to 9 years old (3.44 per 100,000 population). The average incidence was highest amongst Malays (10.97 per 100,000 population), followed by Indians (7.95 per 100,000 population). Stratification according to geographical distribution showed that the state of Malacca had the highest average disease incidence (11.12 per 100,000 population) followed by Pahang (10.08 per 100,000 population). The states of Terengganu, Kelantan, and Perak recorded similar rates of incidence (≈8.00 per 100,000 population), while Johor with the least number of reported cases (1.80 per 100,000 population). Positive relationships were recorded between the number of reported cases with the number of raining days per month and monthly average temperature (p-value<0.05). However, no significant association was noted between rainfall volume and number of reported Leptospirosis cases. This collaborative efforts between medical, academic and governmental institutions has enabled the construction of this comprehensive database that is essential to understand the disease trends in Malaysia and add insights into the prevention and control of this disease.
Collapse
Affiliation(s)
- Douadi Benacer
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia
| | - Kwai Lin Thong
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia
| | - Ng Choung Min
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, Malaysia
| | | | - Renee L Galloway
- Bacterial Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | - Marc Souris
- Institut de Recherche pour le Développement, UR 178 Marseille, France
| | | |
Collapse
|
10
|
Benacer D, Mohd Zain SN, Ahmed AA, Mohd Khalid MKN, Hartskeerl RA, Thong KL. Predominance of the ST143 and ST50 Leptospira clones in the urban rat populations of Peninsular Malaysia. J Med Microbiol 2016; 65:574-577. [PMID: 27058766 DOI: 10.1099/jmm.0.000262] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Douadi Benacer
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia
| | | | - Ahmed A Ahmed
- Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | | | | | - Kwai Lin Thong
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia
| |
Collapse
|
11
|
Abstract
The history and epidemiology of human leptospirosis in Malaysia from 1925 to 2012 are described. Previous studies have demonstrated that leptospirosis is an endemic disease in Malaysia occurring in both urban and rural locations. The number of cases has risen dramatically since the Ministry of Health Malaysia highlighted leptospirosis as a notifiable disease in 2010, with reported cases increasing from 248 cases in 2004 to 3604 in 2012. The incidence of infection among the population suggests that occupation, sex, age, ethnic background, water recreational activities, and sporting events are risk factors. A robust surveillance system is now in place to monitor temporal and spatial changes in the incidence and prevalence of infection and to identify risk areas and disease behavior. Despite extensive studies over the past decade, there is a still a need to describe local serovars in host carriers and the human population, with the view to develop an effective vaccine against leptospirosis.
Collapse
Affiliation(s)
| | | | | | | | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Amsterdam, Netherlands
| | | | | |
Collapse
|
12
|
Moreno LZ, Miraglia F, Lilenbaum W, Neto JSF, Freitas JC, Morais ZM, Hartskeerl RA, da Costa BLP, Vasconcellos SA, Moreno AM. Profiling of Leptospira interrogans, L. santarosai, L. meyeri and L. borgpetersenii by SE-AFLP, PFGE and susceptibility testing--a continuous attempt at species and serovar differentiation. Emerg Microbes Infect 2016; 5:e17. [PMID: 26956446 PMCID: PMC4820670 DOI: 10.1038/emi.2016.16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/25/2015] [Accepted: 11/23/2015] [Indexed: 11/08/2022]
Abstract
Leptospirosis is a widespread systemic zoonosis, considered as reemerging in certain developing countries. Although the cross agglutinin absorption test is still considered the standard method for Leptospira identification, it presents several disadvantages. The aim of this study was to characterize Leptospira spp. isolated from various hosts by genotyping and broth microdilution susceptibility testing in an attempt to differentiate Leptospira species, serogroups and serovars. Forty-seven isolates were studied. They were previously serotyped, and species confirmation was performed by 16S rRNA sequencing. Single-enzyme amplified fragment length polymorphism (SE-AFLP) and pulsed-field gel electrophoresis (PFGE) analysis enabled the distinction of L. interrogans from L. santarosai, L. meyeri and L. borgpetersenii in two main clusters. Among L. interrogans, it was possible to differentiate into two new clusters the serogroup Icterohaemorrhagiae from the serogroups Canicola and Pomona. L. santarosai isolates presented higher genetic variation than the other species in both techniques. Interestingly, the minimum inhibitory concentration (MIC) cluster analysis also provided Leptospira serogroup differentiation. Further studies are necessary regarding serovar Bananal isolates, as they presented the highest MIC values for most of the antimicrobials tested. All studied techniques successfully distinguished Leptospira species and serogroups. Despite being library-dependent methods, these approaches are less labor intensive and more economically viable, particularly SE-AFLP, and can be implemented in most reference laboratories worldwide to enable faster Leptospira typing.
Collapse
Affiliation(s)
- Luisa Z Moreno
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| | - Fabiana Miraglia
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
- Veterinary Bacteriology Laboratory, Department of Microbiology and Parasitology, Fluminense Federal University, Hernani Mello, 101 Niterói/RJ 24210 130, Brazil
| | - Walter Lilenbaum
- Veterinary Bacteriology Laboratory, Department of Microbiology and Parasitology, Fluminense Federal University, Hernani Mello, 101 Niterói/RJ 24210 130, Brazil
| | - José SF Neto
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| | - Julio C Freitas
- Laboratory of Animal Leptospirosis, Londrina State University, Rod Celso Garcia Cid, Londrina/PR 86057 970, Brazil
| | - Zenaide M Morais
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| | - Rudy A Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Royal Tropical Institute, Amsterdam 391105, Netherlands
| | - Barbara LP da Costa
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| | - Silvio A Vasconcellos
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| | - Andrea M Moreno
- Laboratory of Molecular Epidemiology and Antimicrobial Resistance/Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP 05508 270, Brazil
| |
Collapse
|
13
|
Mgode GF, Machang’u RS, Mhamphi GG, Katakweba A, Mulungu LS, Durnez L, Leirs H, Hartskeerl RA, Belmain SR. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts. PLoS Negl Trop Dis 2015; 9:e0004251. [PMID: 26624890 PMCID: PMC4666418 DOI: 10.1371/journal.pntd.0004251] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 10/29/2015] [Indexed: 12/27/2022] Open
Abstract
The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries.
Collapse
Affiliation(s)
- Georgies F. Mgode
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Robert S. Machang’u
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Ginethon G. Mhamphi
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Abdul Katakweba
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Loth S. Mulungu
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Lies Durnez
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Herwig Leirs
- Evolutionary Ecology Group, University of Antwerp, Antwerpen, Belgium
| | - Rudy A. Hartskeerl
- Royal Tropical Institute (KIT), KIT Biomedical Research, WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Amsterdam, The Netherlands
| | - Steven R. Belmain
- Natural Resources Institute, University of Greenwich, United Kingdom
| |
Collapse
|
14
|
Goeijenbier M, Gasem MH, Meijers JC, Hartskeerl RA, Ahmed A, Goris MG, Isbandrio B, Schuller SS, Osterhaus AD, Martina BE, van Gorp EC, Nally JE, Wagenaar JF. Markers of endothelial cell activation and immune activation are increased in patients with severe leptospirosis and associated with disease severity. J Infect 2015; 71:437-46. [DOI: 10.1016/j.jinf.2015.05.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/28/2015] [Accepted: 05/18/2015] [Indexed: 01/06/2023]
|
15
|
Yang B, de Vries SG, Visser BJ, Nagel IM, GA Goris M, Leeflang MMG, Grobusch MP, Hartskeerl RA. Molecular and antigen detection tests for leptospirosis. Hippokratia 2015. [DOI: 10.1002/14651858.cd011871] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Bada Yang
- Academic Medical Center; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine; Meibergdreef 9 Amsterdam Noord-Holland Netherlands 1105 AZ
| | - Sophia G de Vries
- Academic Medical Center; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine; Meibergdreef 9 Amsterdam Noord-Holland Netherlands 1105 AZ
| | - Benjamin J Visser
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center; Meibergdreef 9 Amsterdam Noord-Holland Netherlands 1105 AZ
| | | | - Marga GA Goris
- Royal Tropical Institute (KIT); KIT Biomedical Research; Meibergdreef 39 Amsterdam 1105 AZ Netherlands Noord Holland
| | - Mariska MG Leeflang
- Academic Medical Center, University of Amsterdam; Department of Clinical Epidemiology, Biostatistics and Bioinformatics; P.O. Box 22700 Amsterdam Netherlands 1100 DE
| | - Martin P Grobusch
- Academic Medical Center; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine; Meibergdreef 9 Amsterdam Noord-Holland Netherlands 1105 AZ
| | - Rudy A Hartskeerl
- Royal Tropical Institute (KIT); KIT Biomedical Research; Meibergdreef 39 Amsterdam 1105 AZ Netherlands Noord Holland
| |
Collapse
|
16
|
Abstract
The general goal of reference centres is to support the community, from diagnostic laboratories to research institutions, in the execution of their work by providing reference strains and reagents and giving instructions and recommendations to individual colleagues and national and international organisations on a wide variety of issues. There are different levels of reference centres, from local to international, with an increasing package of tasks and responsibilities. Local reference centres might limit activities to diagnostic confirmation by applying standard testing, while international reference centres cover a wider range of activities from design, validation and harmonisation of diagnostic and reference technologies to international monitoring associated with recommendations on the global burden and distribution of leptospirosis and its prevention and control to national and international health decision makers. This chapter focusses on four major pillars constituting reference tasks in addition to the obvious provision of reference substances, i.e. Research and training, Diagnosis, Identification of Leptospira and Surveillance. Due to financial and organisational constraints, reference centres are restricted in their capacity for basic research and consequently focus on applied research into various aspects of leptospirosis. They offer training, either individually or groupwise, that might vary from standard technologies to novel sophisticated methodologies, depending on the need and requests of the trainee. Most reference centres are involved in the confirmation of preliminary diagnosis obtained at peripheral levels, such as local hospitals and health centres, while other major activities involve the design and validation of diagnostics, their international harmonisation and quality assurance. Identification of causative Leptospira strains (or serovars) is key to the identification of infection sources and is critical for surveillance. Hence, reference centres also focus on the development, application and provision of methods that are required for unambiguous characterisation of new and recognised Leptospira strains and the maintenance of the integrity of strain collections. In line with their central role, reference centres are frequently associated with local, national and/or international surveillance activities linked to an advisory role and the production of guidelines. Such surveillance activities usually comprise collation of morbidity and mortality data, signalling of outbreaks and the investigation of infection sources and risks.
Collapse
Affiliation(s)
- Rudy A Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, Royal Tropical Institute, KIT Biomedical Research, Meibergdreef 39, 1105 AZ, Amsterdam, The Netherlands,
| | | |
Collapse
|
17
|
Abstract
Leptospirosis is a major zoonosis with worldwide distribution. Conventional serological typing is arduous and time consuming. Genotyping is increasingly applied for the typing and identification of leptospires and contributes to genetic and virulence divergence and molecular epidemiological characteristics such as host versus leptospires population interactions and dynamics. Presently, multilocus sequence typing (MLST) is the most robust approach. In this chapter, we describe the practical steps of two major multilocus sequence typing methods for leptospires. The first method (denoted as the 6 L scheme) is based on genotyping by phylogeny using concatenated sequences derived from six loci, including genes that encode outer membrane proteins and rrs and can be used for typing pathogenic species and strains of intermediate species. The second method (referred to as the 7 L scheme) uses seven loci on housekeeping genes and allows the analysis of seven major Leptospira pathogenic species. The 7 L scheme is web based and includes the option to analyze sequence types (STs).
Collapse
Affiliation(s)
- Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | | | | |
Collapse
|
18
|
Ferreira AS, Costa P, Rocha T, Amaro A, Vieira ML, Ahmed A, Thompson G, Hartskeerl RA, Inácio J. Direct detection and differentiation of pathogenic Leptospira species using a multi-gene targeted real time PCR approach. PLoS One 2014; 9:e112312. [PMID: 25398140 PMCID: PMC4232388 DOI: 10.1371/journal.pone.0112312] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/03/2014] [Indexed: 11/18/2022] Open
Abstract
Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpeteresenii and L. noguchii, which constitute the veterinary most relevant pathogenic species of Leptospira. The method uses sets of species-specific probes, and respective flanking primers, designed from ompL1 and secY gene sequences. To monitor the presence of inhibitors, a duplex amplification assay targeting both the mammal β-actin and the leptospiral lipL32 genes was implemented. The analytical sensitivity of all primer and probe sets was estimated to be <10 genome equivalents (GE) in the reaction mixture. Application of the amplification reactions on genomic DNA from a variety of pathogenic and non-pathogenic Leptospira strains and other non-related bacteria revealed a 100% analytical specificity. Additionally, pathogenic leptospires were successfully detected in five out of 29 tissue samples from animals (Mus spp., Rattus spp., Dolichotis patagonum and Sus domesticus). Two samples were infected with L. borgpetersenii, two with L. interrogans and one with L. kirschneri. The possibility to detect and identify these pathogenic agents to the species level in domestic and wildlife animals reinforces the diagnostic information and will enhance our understanding of the epidemiology of leptopirosis.
Collapse
Affiliation(s)
- Ana Sofia Ferreira
- Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV, I.P.), Unidade Estratégica de Investigação e Serviços em Produção e Saúde Animal, Lisboa, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
- * E-mail: (ASF); (JI)
| | - Pedro Costa
- Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV, I.P.), Unidade Estratégica de Investigação e Serviços em Produção e Saúde Animal, Lisboa, Portugal
- Unidade de Microbiologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Teresa Rocha
- Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV, I.P.), Unidade Estratégica de Investigação e Serviços em Produção e Saúde Animal, Lisboa, Portugal
| | - Ana Amaro
- Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV, I.P.), Unidade Estratégica de Investigação e Serviços em Produção e Saúde Animal, Lisboa, Portugal
| | - Maria Luísa Vieira
- Unidade de Microbiologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, KIT Biomedical Research, Amsterdam, The Netherlands
| | - Gertrude Thompson
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
- Research Center in Biodiversity and Genetic Resources (CIBIO-ICETA), Universidade do Porto, Porto, Portugal
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, KIT Biomedical Research, Amsterdam, The Netherlands
| | - João Inácio
- Instituto Nacional de Investigação Agrária e Veterinária, I.P. (INIAV, I.P.), Unidade Estratégica de Investigação e Serviços em Produção e Saúde Animal, Lisboa, Portugal
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom
- * E-mail: (ASF); (JI)
| |
Collapse
|
19
|
de Vries SG, Visser BJ, Nagel IM, Goris MGA, Hartskeerl RA, Grobusch MP. Leptospirosis in Sub-Saharan Africa: a systematic review. Int J Infect Dis 2014; 28:47-64. [PMID: 25197035 DOI: 10.1016/j.ijid.2014.06.013] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/13/2014] [Accepted: 06/14/2014] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Leptospirosis is an emerging zoonotic infection worldwide, possibly due to climate change and demographic shifts. It is regarded as endemic in Sub-Saharan Africa; however, for most countries scarce epidemiological data, if any, exist. The primary objectives were to describe the prevalence of leptospirosis in countries in Sub-Saharan Africa, and to develop options for prevention and control in the future. METHODS A systematic review was conducted to determine the prevalence of leptospirosis in Sub-Saharan Africa; the PRISMA guidelines were followed. Medline/PubMed, Embase, The Cochrane Library, Web of Science, BIOSIS Previews, the African Index Medicus, AJOL, and Google Scholar were searched. RESULTS Information about the prevalence and incidence of leptospirosis in humans is available, but remains scarce for many countries. Data are unavailable or outdated for many countries, particularly those in Central Africa. Most data are available from animals, probably due to the economic losses caused by leptospirosis in livestock. In humans, leptospirosis is an important cause of febrile illness in Sub-Saharan Africa. It concerns numerous serogroups, harboured by many different animal carriers. DISCUSSION A wide variety of data was identified. Prevalence rates vary throughout the continent and more research, especially in humans, is needed to reliably gauge the extent of the problem. Preventive measures need to be reconsidered to control outbreaks in the future.
Collapse
Affiliation(s)
- Sophia G de Vries
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1100 DE, room F4-220, Amsterdam, Netherlands
| | - Benjamin J Visser
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1100 DE, room F4-220, Amsterdam, Netherlands
| | - Ingeborg M Nagel
- Medical Library, Academic Medical Centre, University of Amsterdam, Netherlands
| | - Marga G A Goris
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Amsterdam, Netherlands
| | - Rudy A Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Amsterdam, Netherlands
| | - Martin P Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1100 DE, room F4-220, Amsterdam, Netherlands.
| |
Collapse
|
20
|
Goeijenbier M, Hartskeerl RA, Reimerink J, Verner-Carlsson J, Wagenaar JF, Goris MG, Martina BE, Lundkvist Å, Koopmans M, Osterhaus AD, van Gorp EC, Reusken CB. The hanta hunting study: underdiagnosis of Puumala hantavirus infections in symptomatic non-travelling leptospirosis-suspected patients in the Netherlands, in 2010 and April to November 2011. Euro Surveill 2014; 19. [DOI: 10.2807/1560-7917.es2014.19.32.20878] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leptospirosis and haemorrhagic fever with renal syndrome (HFRS) are hard to distinguish clinically since these two important rodent-borne zoonoses share hallmark symptoms such as renal failure and haemorrhage. Leptospirosis is caused by infection with a spirochete while HFRS is the result of an infection with certain hantaviruses. Both diseases are relatively rare in the Netherlands. Increased incidence of HFRS has been observed since 2007 in countries that border the Netherlands. Since a similar rise in incidence has not been registered in the Netherlands, we hypothesise that due to overlapping clinical manifestations, hantavirus infections may be confused with leptospirosis, leading to underdiagnosis. Therefore, we tested a cohort of non-travelling Dutch patients with symptoms compatible with leptospirosis, but with a negative diagnosis, during 2010 and from April to November 2011. Sera were screened with pan-hantavirus IgG and IgM enzyme-linked immunosorbent assays (ELISAs). Sera with IgM reactivity were tested by immunofluorescence assay (IFA). ELISA (IgM positive) and IFA results were confirmed using focus reduction neutralisation tests (FRNTs). We found hantavirus-specific IgG and/or IgM antibodies in 4.3% (11/255) of samples taken in 2010 and in 4.1% (6/146) of the samples during the 2011 period. After FRNT confirmation, seven patients were classed as having acute Puumala virus infections. A review of hantavirus diagnostic requests revealed that at least three of the seven confirmed acute cases as well as seven probable acute cases of hantavirus infection were missed in the Netherlands during the study period.
Collapse
Affiliation(s)
- M Goeijenbier
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
| | - R A Hartskeerl
- Royal Tropical Institute (KIT), KIT Biomedical Research, Amsterdam, the Netherlands
| | - J Reimerink
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | | | - J F Wagenaar
- Royal Tropical Institute (KIT), KIT Biomedical Research, Amsterdam, the Netherlands
| | - M G Goris
- Royal Tropical Institute (KIT), KIT Biomedical Research, Amsterdam, the Netherlands
| | - B E Martina
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
| | - Å Lundkvist
- Public Health Agency of Sweden, Solna, Sweden
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - M Koopmans
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
| | - A D Osterhaus
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
| | - E C van Gorp
- These authors share senior authorship
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
| | - C B Reusken
- Erasmus MC, Department of Virology, Rotterdam, the Netherlands
- These authors share senior authorship
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| |
Collapse
|
21
|
Ahmed A, van der Linden H, Hartskeerl RA. Development of a recombinase polymerase amplification assay for the detection of pathogenic Leptospira. Int J Environ Res Public Health 2014; 11:4953-64. [PMID: 24814943 PMCID: PMC4053868 DOI: 10.3390/ijerph110504953] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/08/2014] [Accepted: 04/30/2014] [Indexed: 02/07/2023]
Abstract
Detection of leptospires based on DNA amplification techniques is essential for the early diagnosis of leptospirosis when anti-Leptospira antibodies are below the detection limit of most serological tests. In middle and low income countries where leptospirosis is endemic, routine implementation of real-time PCR is financially and technically challenging due to the requirement of expensive thermocycler equipment. In this study we report the development and evaluation of a novel isothermal recombinase polymerase amplification assay (RPA) for detection of pathogenic Leptospira based on TwistAmp chemistry. RPA enabled the detection of less than two genome copies per reaction. Retrospective evaluation revealed a high diagnostic accuracy (sensitivity and specificity of 94.7% and 97.7%, respectively) compared to culturing as the reference standard. RPA presents a powerful tool for the early diagnosis of leptospirosis in humans and in animals. Furthermore, it enables the detection of the causative agent in reservoirs and environment, and as such is a valuable adjunct to current tools for surveillance and early outbreak warning.
Collapse
Affiliation(s)
- Ahmed Ahmed
- KIT Biomedical Research, WHO/FAO/OIE and National Leptospirosis Reference Centre, Royal Tropical Institute, Meibergdreef 39, Amsterdam 1105, The Netherlands.
| | - Hans van der Linden
- KIT Biomedical Research, WHO/FAO/OIE and National Leptospirosis Reference Centre, Royal Tropical Institute, Meibergdreef 39, Amsterdam 1105, The Netherlands.
| | - Rudy A Hartskeerl
- KIT Biomedical Research, WHO/FAO/OIE and National Leptospirosis Reference Centre, Royal Tropical Institute, Meibergdreef 39, Amsterdam 1105, The Netherlands.
| |
Collapse
|
22
|
Affiliation(s)
- Marga G.A. Goris
- Royal Tropical Institute (KIT), KIT Biomedical Research, WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis Amsterdam The Netherlands
| | - Rudy A. Hartskeerl
- Royal Tropical Institute (KIT), KIT Biomedical Research, WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis Amsterdam The Netherlands
| |
Collapse
|
23
|
Halliday JEB, Knobel DL, Allan KJ, de C. Bronsvoort BM, Handel I, Agwanda B, Cutler SJ, Olack B, Ahmed A, Hartskeerl RA, Njenga MK, Cleaveland S, Breiman RF. Urban leptospirosis in Africa: a cross-sectional survey of Leptospira infection in rodents in the Kibera urban settlement, Nairobi, Kenya. Am J Trop Med Hyg 2013; 89:1095-1102. [PMID: 24080637 PMCID: PMC3854886 DOI: 10.4269/ajtmh.13-0415] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Leptospirosis is a widespread but under-reported cause of morbidity and mortality. Global re-emergence of leptospirosis has been associated with the growth of informal urban settlements in which rodents are thought to be important reservoir hosts. Understanding the multi-host epidemiology of leptospirosis is essential to control and prevent disease. A cross-sectional survey of rodents in the Kibera settlement in Nairobi, Kenya was conducted in September–October 2008 to demonstrate the presence of pathogenic leptospires. A real-time quantitative polymerase chain reaction showed that 41 (18.3%) of 224 rodents carried pathogenic leptospires in their kidneys, and sequence data identified Leptospira interrogans and L. kirschneri in this population. Rodents of the genus Mus (37 of 185) were significantly more likely to be positive than those of the genus Rattus (4 of 39; odds ratio = 15.03). Questionnaire data showed frequent contact between humans and rodents in Kibera. This study emphasizes the need to quantify the public health impacts of this neglected disease at this and other urban sites in Africa.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Sarah Cleaveland
- *Address correspondence to Sarah Cleaveland, Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G11 8QQ, United Kingdom. E-mail:
| | | |
Collapse
|
24
|
Valverde MDLA, Goris MGA, González V, Anchia ME, Díaz P, Ahmed A, Hartskeerl RA. New serovars of Leptospira isolated from patients in Costa Rica: implications for public health. J Med Microbiol 2013; 62:1263-1271. [PMID: 23788592 DOI: 10.1099/jmm.0.058545-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Leptospira strains JICH 05 and INCIENSA 04 were isolated from hospitalized leptospirosis patients in the province of Puntarenas, Costa Rica. The isolates produced agglutination titres notably against members of serogroups Pyrogenes and Tarassovi, respectively, but appeared serologically unique in the cross agglutinin absorption test (CAAT). Therefore, JICH 05 and INCIENSA 04 were considered to represent two new serovars, designated Corredores and Costa Rica of the serogroups Pyrogenes and Tarassovi, respectively. Multilocus sequence genotyping revealed that both strain INCIENSA 04 and strain JICH 05 belong to Leptospira santarosai. These two new serovars are in addition to various other recently identified highly virulent serovars, including the new L. santarosai, serovar Arenal. Considering the fact that isolation and typing of leptospires from patients has only recently been introduced in Costa Rica, these findings suggest that various known and unknown virulent serovars of Leptospira are circulating in this country and probably beyond, thus posing a severe threat to public and probably veterinary health in the region.
Collapse
Affiliation(s)
- Ma de Los A Valverde
- Costa Rican Institute for Research in Nutrition and Health (INCIENSA), National Reference Centre for Leptospirosis, Tres Rios, Costa Rica
| | - M G A Goris
- KIT Biomedical Research, WHO/FAO/OIE Leptospirosis Reference Centre, Amsterdam, The Netherlands
| | - V González
- Area Rectora Salud Corredores (Ministerio de Salud), Corredores, Costa Rica
| | - M E Anchia
- Ciudad Neilly Hospital (Caja Costarricense de Seguro Social), Corredores, Costa Rica
| | - P Díaz
- Ciudad Neilly Hospital (Caja Costarricense de Seguro Social), Corredores, Costa Rica
| | - A Ahmed
- KIT Biomedical Research, WHO/FAO/OIE Leptospirosis Reference Centre, Amsterdam, The Netherlands
| | - R A Hartskeerl
- KIT Biomedical Research, WHO/FAO/OIE Leptospirosis Reference Centre, Amsterdam, The Netherlands
| |
Collapse
|
25
|
Abstract
To increase knowledge of leptospirosis in the Netherlands and identify changing trends of this disease over time, we analyzed historical passive surveillance reports for an 84-year period (1925-2008). We found that 2,553 mainly severe leptospirosis cases were diagnosed (average annual incidence rate 0.25 cases/100,000 population). The overall case-fatality rate for patients with reported leptospirosis was 6.5% but decreased over the period, probably because of improved treatment. Ninety percent of reported leptospirosis cases were in male patients. Most autochthonous leptospirosis infections were associated with recreational exposures, but 15.5% of the cases were attributed to accidents that resulted in injury and to concomitant water contact. Since the end of the 1950s, the proportion of imported infections gradually increased, reaching 53.1% of the total during 2005-2008. Most (80.1%) imported infections were associated with sporting and adventurous vacation activities.
Collapse
Affiliation(s)
- Marga G A Goris
- Royal Tropical Institute of Biomedical Research, Meibergdreef 39, 1105 AZ Amsterdam, the Netherlands.
| | | | | | | | | |
Collapse
|
26
|
Boonsilp S, Thaipadungpanit J, Amornchai P, Wuthiekanun V, Bailey MS, Holden MTG, Zhang C, Jiang X, Koizumi N, Taylor K, Galloway R, Hoffmaster AR, Craig S, Smythe LD, Hartskeerl RA, Day NP, Chantratita N, Feil EJ, Aanensen DM, Spratt BG, Peacock SJ. A single multilocus sequence typing (MLST) scheme for seven pathogenic Leptospira species. PLoS Negl Trop Dis 2013; 7:e1954. [PMID: 23359622 PMCID: PMC3554523 DOI: 10.1371/journal.pntd.0001954] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/26/2012] [Indexed: 01/20/2023] Open
Abstract
Background The available Leptospira multilocus sequence typing (MLST) scheme supported by a MLST website is limited to L. interrogans and L. kirschneri. Our aim was to broaden the utility of this scheme to incorporate a total of seven pathogenic species. Methodology and Findings We modified the existing scheme by replacing one of the seven MLST loci (fadD was changed to caiB), as the former gene did not appear to be present in some pathogenic species. Comparison of the original and modified schemes using data for L. interrogans and L. kirschneri demonstrated that the discriminatory power of the two schemes was not significantly different. The modified scheme was used to further characterize 325 isolates (L. alexanderi [n = 5], L. borgpetersenii [n = 34], L. interrogans [n = 222], L. kirschneri [n = 29], L. noguchii [n = 9], L. santarosai [n = 10], and L. weilii [n = 16]). Phylogenetic analysis using concatenated sequences of the 7 loci demonstrated that each species corresponded to a discrete clade, and that no strains were misclassified at the species level. Comparison between genotype and serovar was possible for 254 isolates. Of the 31 sequence types (STs) represented by at least two isolates, 18 STs included isolates assigned to two or three different serovars. Conversely, 14 serovars were identified that contained between 2 to 10 different STs. New observations were made on the global phylogeography of Leptospira spp., and the utility of MLST in making associations between human disease and specific maintenance hosts was demonstrated. Conclusion The new MLST scheme, supported by an updated MLST website, allows the characterization and species assignment of isolates of the seven major pathogenic species associated with leptospirosis. Leptospirosis is a common zoonotic disease worldwide. Genotyping of the causative organisms provides important insights into disease transmission and informs preventive strategies and vaccine development. Multilocus sequence typing (MLST) is the most widespread genotyping methodology for bacterial pathogens, but the Leptospira scheme supported by a public MLST database is currently only applicable to L. interrogans and L. kirschneri. The purpose of this study was to extend the scheme to a total of seven pathogenic Leptospira species. This was achieved through the development of a modified scheme in which one of the seven MLST loci was replaced, together with newly designed primers for the remaining 6 loci. Comparison of the original and modified scheme demonstrated that they were very similar, hence sequence type (ST) assignments were largely carried over to the modified scheme. Phylogenetic trees reconstructed from concatenated sequences of the seven loci of the modified scheme demonstrated perfect classification of isolates into seven pathogenic species, which resided in clearly distinct phylogenetic clusters. Congruence was low between STs and serovars. The MLST scheme was used to gain new insights into the population genetic structure of Leptospira species associated with clinical disease and maintenance hosts in Asia.
Collapse
Affiliation(s)
- Siriphan Boonsilp
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Janjira Thaipadungpanit
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- * E-mail:
| | - Premjit Amornchai
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Vanaporn Wuthiekanun
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Mark S. Bailey
- Department of Infection and Tropical Medicine, Birmingham Heartlands Hospital, West Midlands, United Kingdom
| | | | - Cuicai Zhang
- Department of Leptospirosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Xiugao Jiang
- Department of Leptospirosis, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Nobuo Koizumi
- Department of Bacteriology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kyle Taylor
- Laboratory of Wildlife Biology and Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Renee Galloway
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Diseases Control and Prevention, Atlanta, Georgia, United States of America
| | - Alex R. Hoffmaster
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Diseases Control and Prevention, Atlanta, Georgia, United States of America
| | - Scott Craig
- WHO/FAO/OIE Collaborating Center for Reference and Research on Leptospirosis, Queensland Health Forensic and Scientific Services, Health Services Support Agency, Queensland Health, Brisbane, Queensland, Australia
| | - Lee D. Smythe
- WHO/FAO/OIE Collaborating Center for Reference and Research on Leptospirosis, Queensland Health Forensic and Scientific Services, Health Services Support Agency, Queensland Health, Brisbane, Queensland, Australia
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Royal Tropical Institute, Amsterdam, The Netherlands
| | - Nicholas P. Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Center for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Churchill Hospital, Oxford, United Kingdom
| | - Narisara Chantratita
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Edward J. Feil
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - David M. Aanensen
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Brian G. Spratt
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Sharon J. Peacock
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
| |
Collapse
|
27
|
Smythe L, Adler B, Hartskeerl RA, Galloway RL, Turenne CY, Levett PN, The International Committee On Systematics Of Prokaryotes Subcommittee On The Taxonomy Of. Classification of Leptospira genomospecies 1, 3, 4 and 5 as Leptospira alstonii sp. nov., Leptospira vanthielii sp. nov., Leptospira terpstrae sp. nov. and Leptospira yanagawae sp. nov., respectively. Int J Syst Evol Microbiol 2012; 63:1859-1862. [PMID: 22984140 DOI: 10.1099/ijs.0.047324-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The genus Leptospira currently comprises 16 named species. In addition, four unnamed hybridization groups were designated Leptospira genomospecies 1, 3, 4 and 5. These groups represent valid species-level taxa, but were not assigned names in the original description by Brenner et al. [Int J Syst Bacteriol 49, 839-858 (1999)]. To rectify this situation, it is proposed that Leptospira genomospecies 1, genomospecies 3, genomospecies 4 and genomospecies 5 should be classified as Leptospira alstonii sp. nov., Leptospira vanthielii sp. nov., Leptospira terpstrae sp. nov. and Leptospira yanagawae sp. nov., respectively, with strains L. alstonii 79601(T) ( = ATCC BAA-2439(T)), L. vanthielii WaZ Holland(T) ( = ATCC 700522(T)), L. terpstrae LT 11-33(T) ( = ATCC 700639(T)) and L. yanagawae Sao Paulo(T) ( = ATCC 700523(T)) as the type strains. The type strains are also available from the culture collections of the WHO Collaborating Centres in Amsterdam, The Netherlands, and Brisbane, Australia.
Collapse
Affiliation(s)
- L Smythe
- WHO/FAO/OIE Collaborating Centre for Reference & Research on Leptospirosis, Western Pacific Region, Health Support Services Agency, Queensland Health, Brisbane, Australia
| | - B Adler
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Victoria, Australia
| | - R A Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Royal Tropical Institute, Amsterdam, The Netherlands
| | - R L Galloway
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - C Y Turenne
- Saskatchewan Disease Control Laboratory, Regina, Saskatchewan, Canada
| | - P N Levett
- Saskatchewan Disease Control Laboratory, Regina, Saskatchewan, Canada
| | | |
Collapse
|
28
|
Costa F, Martinez-Silveira MS, Hagan JE, Hartskeerl RA, Dos Reis MG, Ko AI. Surveillance for leptospirosis in the Americas, 1996-2005: a review of data from ministries of health. Rev Panam Salud Publica 2012; 32:169-77. [PMID: 23183556 PMCID: PMC3970205 DOI: 10.1590/s1020-49892012000900001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Accepted: 05/26/2012] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE To characterize current leptospirosis reporting practices in the Americas. METHODS Information was collected from the official websites of national ministries of health from the Americas region and two international organizations; personal communications; and three international morbidity databases. For all sources other than the morbidity databases, the review was limited to official reports citing clinically suspected and laboratory confirmed leptospirosis cases or deaths during the period 1996-2005. RESULTS A total of 73 out of 1 644 reports met the selection criteria and were included in the analysis. Published leptospirosis data were available from half of the countries/sovereign territories (24 out of 48), and 18 of them had mandatory notification policies for leptospirosis. The sum of the median number of leptospirosis cases notified annually by the 24 countries/territories was 4 713.5, but just three countries (Brazil, Costa Rica, and Cuba) accounted for 83.1% (3 9cas20 es) of the notifications. Eight (16.7%) countries reported deaths due to leptospirosis. The sum of the median number of deaths reported annually for the eight countries was 380, but 349 (91.8%) were reported by Brazil. CONCLUSIONS Notification practices in the Americas for leptospirosis are limited. Therefore, the numbers of cases and deaths reported are not representative for the region. The lack of leptospirosis data for many countries/territories may reflect weaknesses in certain aspects of national surveillance systems, including mandatory reporting policies, clinical laboratory infrastructure for performing case confirmation, and capacity to collect reported cases. Improved surveillance of leptospirosis cases and deaths in the Americas is needed to allow monitoring of regional epidemiological patterns and to estimate the burden of this important disease.
Collapse
Affiliation(s)
- Federico Costa
- Laboratório de Patologia e Biologia Molecular, Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Ministério da Saúde, Salvador, Brazil.
| | | | | | | | | | | |
Collapse
|
29
|
Helmerhorst HJF, van Tol EN, Tuinman PR, de Vries PJ, Hartskeerl RA, Grobusch MP, Hovius JW. Severe pulmonary manifestation of leptospirosis. Neth J Med 2012; 70:215-221. [PMID: 22744922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Based on increasing incidence and the occurrence of worldwide outbreaks, leptospirosis is recognised as an emerging zoonosis. Severe manifestations are associated with high morbidity and mortality rates and may therefore pose an important risk to public health, especially in certain high prevalence areas. A considerable number of infections progress to a severe form, which can present as the well-known triad of jaundice, impaired renal function and haemorrhage, known as Weil's disease. The severe pulmonary form of leptospirosis (SPFL) is a less known entity and is characterised by intra-alveolar haemorrhage and can lead to acute respiratory failure and death when adequate treatment fails. Prognostic factors correlating with severity and survival of leptospirosis include indicators of renal failure, pulmonary involvement and electrolyte imbalances. We report an imported case of SPFL in a returning traveller, and review the literature discussing epidemiology, clinical manifestations, prognostic factors and treatment of this resurgent disease.
Collapse
Affiliation(s)
- H J F Helmerhorst
- Department of Internal Medicine, Academic Medical Center, University of Amsterdam, the Netherlands
| | | | | | | | | | | | | |
Collapse
|
30
|
Ahmed A, L. B. M. Klaasen H, van der Veen M, van der Linden H, G. A. Goris M, A. Hartskeerl R. Evaluation of Real-Time PCR and Culturing for the Detection of Leptospires in Canine Samples. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/aim.2012.22021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
31
|
Ahmed A, Thaipadungpanit J, Boonsilp S, Wuthiekanun V, Nalam K, Spratt BG, Aanensen DM, Smythe LD, Ahmed N, Feil EJ, Hartskeerl RA, Peacock SJ. Comparison of two multilocus sequence based genotyping schemes for Leptospira species. PLoS Negl Trop Dis 2011; 5:e1374. [PMID: 22087342 PMCID: PMC3210738 DOI: 10.1371/journal.pntd.0001374] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 09/13/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Several sequence based genotyping schemes have been developed for Leptospira spp. The objective of this study was to genotype a collection of clinical and reference isolates using the two most commonly used schemes and compare and contrast the results. METHODS AND FINDINGS A total of 48 isolates consisting of L. interrogans (n = 40) and L. kirschneri (n = 8) were typed by the 7 locus MLST scheme described by Thaipadungpanit et al., and the 6 locus genotyping scheme described by Ahmed et al., (termed 7L and 6L, respectively). Two L. interrogans isolates were not typed using 6L because of a deletion of three nucleotides in lipL32. The remaining 46 isolates were resolved into 21 sequence types (STs) by 7L, and 30 genotypes by 6L. Overall nucleotide diversity (based on concatenated sequence) was 3.6% and 2.3% for 7L and 6L, respectively. The D value (discriminatory ability) of 7L and 6L were comparable, i.e. 92.0 (95% CI 87.5-96.5) vs. 93.5 (95% CI 88.6-98.4). The dN/dS ratios calculated for each locus indicated that none were under positive selection. Neighbor joining trees were reconstructed based on the concatenated sequences for each scheme. Both trees showed two distinct groups corresponding to L. interrogans and L. kirschneri, and both identified two clones containing 10 and 7 clinical isolates, respectively. There were six instances in which 6L split single STs as defined by 7L into closely related clusters. We noted two discrepancies between the trees in which the genetic relatedness between two pairs of strains were more closely related by 7L than by 6L. CONCLUSIONS This genetic analysis indicates that the two schemes are comparable. We discuss their practical advantages and disadvantages.
Collapse
Affiliation(s)
- Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Hartskeerl RA, Collares-Pereira M, Ellis WA. Emergence, control and re-emerging leptospirosis: dynamics of infection in the changing world. Clin Microbiol Infect 2011; 17:494-501. [PMID: 21414083 DOI: 10.1111/j.1469-0691.2011.03474.x] [Citation(s) in RCA: 249] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Globally, leptospirosis poses an increasing public health problem, as evidenced by markedly increasing incidence rates and multiple outbreaks in all continents. Yet, the disease is severely neglected and hence, its global burden is largely unknown. The estimated incidence of about half a million severe human cases annually is probably an underestimation while the burden for animal health is unknown. It is anticipated that current international initiatives will assess the global burden of leptospirosis, while mathematical modelling of transmission dynamics will allow the identification and testing of appropriate intervention and outbreak response measures within the coming years.
Collapse
Affiliation(s)
- R A Hartskeerl
- WHO/FAO/OIE and National Leptospirosis Reference Centre, KIT Biomedical Research, Amsterdam, the Netherlands
| | | | | |
Collapse
|
33
|
Bezerra da Silva J, Carvalho E, Hartskeerl RA, Ho PL. Erratum to: Evaluation of the Use of Selective PCR Amplification of LPS Biosynthesis Genes for Molecular Typing of Leptospira at the Serovar Level. Curr Microbiol 2011. [DOI: 10.1007/s00284-010-9772-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
34
|
Cerqueira GM, McBride AJA, Hartskeerl RA, Ahmed N, Dellagostin OA, Eslabão MR, Nascimento ALTO. Bioinformatics describes novel Loci for high resolution discrimination of leptospira isolates. PLoS One 2010; 5:e15335. [PMID: 21124728 PMCID: PMC2955542 DOI: 10.1371/journal.pone.0015335] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 08/09/2010] [Indexed: 11/19/2022] Open
Abstract
Background Leptospirosis is one of the most widespread zoonoses in the world and with over 260 pathogenic serovars there is an urgent need for a molecular system of classification. The development of multilocus sequence typing (MLST) schemes for Leptospira spp. is addressing this issue. The aim of this study was to identify loci with potential to enhance Leptospira strain discrimination by sequencing-based methods. Methodology and Principal Findings We used bioinformatics to evaluate pre-existing loci with the potential to increase the discrimination of outbreak strains. Previously deposited sequence data were evaluated by phylogenetic analyses using either single or concatenated sequences. We identified and evaluated the applicability of the ligB, secY, rpoB and lipL41 loci, individually and in combination, to discriminate between 38 pathogenic Leptospira strains and to cluster them according to the species they belonged to. Pairwise identity among the loci ranged from 82.0–92.0%, while interspecies identity was 97.7–98.5%. Using the ligB-secY-rpoB-lipL41 superlocus it was possible to discriminate 34/38 strains, which belong to six pathogenic Leptospira species. In addition, the sequences were concatenated with the superloci from 16 sequence types from a previous MLST scheme employed to study the association of a leptospiral clone with an outbreak of human leptospirosis in Thailand. Their use enhanced the discriminative power of the existing scheme. The lipL41 and rpoB loci raised the resolution from 81.0–100%, but the enhanced scheme still remains limited to the L. interrogans and L. kirschneri species. Conclusions As the first aim of our study, the ligB-secY-rpoB-lipL41 superlocus demonstrated a satisfactory level of discrimination among the strains evaluated. Second, the inclusion of the rpoB and lipL41 loci to a MLST scheme provided high resolution for discrimination of strains within L. interrogans and L. kirschneri and might be useful in future epidemiological studies.
Collapse
|
35
|
Murray GL, Srikram A, Henry R, Hartskeerl RA, Sermswan RW, Adler B. Mutations affecting Leptospira interrogans lipopolysaccharide attenuate virulence. Mol Microbiol 2010; 78:701-9. [PMID: 20807198 DOI: 10.1111/j.1365-2958.2010.07360.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Leptospira interrogans is the causative agent of leptospirosis. Lipopolysaccharide (LPS) is the major outer membrane component of L. interrogans. It is the dominant antigen recognized during infection and the basis for serological classification. The structure of LPS and its role in pathogenesis are unknown. We describe two defined mutants of L. interrogans serovar Manilae with transposon insertions in the LPS locus. Mutant M895 was disrupted in gene la1641 encoding a protein with no known homologues. M1352 was disrupted in a gene unique to serovar Manilae also encoding a protein of unknown function. M895 produced truncated LPS while M1352 showed little or no change in LPS molecular mass. Both mutants showed altered agglutination titres against rabbit antiserum and against a panel of LPS-specific monoclonal antibodies. The mutants were severely attenuated in virulence via the intraperitoneal route of infection, and were cleared from the host animal by 3 days after infection. M895 was also highly attenuated via the mucosal infection route. Resistance to complement in human serum was unaltered for both mutants. While complementation of mutants was not possible, the attenuation of two independently derived LPS mutants demonstrates for the first time that LPS plays an essential role leptospiral virulence.
Collapse
Affiliation(s)
- Gerald L Murray
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | | | | | | | | | | |
Collapse
|
36
|
Nalam K, Ahmed A, Devi SM, Francalacci P, Baig M, Sechi LA, Hartskeerl RA, Ahmed N. Genetic affinities within a large global collection of pathogenic Leptospira: implications for strain identification and molecular epidemiology. PLoS One 2010; 5:e12637. [PMID: 20805987 PMCID: PMC2929200 DOI: 10.1371/journal.pone.0012637] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 08/15/2010] [Indexed: 02/06/2023] Open
Abstract
Leptospirosis is an important zoonosis with widespread human health implications. The non-availability of accurate identification methods for the individualization of different Leptospira for outbreak investigations poses bountiful problems in the disease control arena. We harnessed fluorescent amplified fragment length polymorphism analysis (FAFLP) for Leptospira and investigated its utility in establishing genetic relationships among 271 isolates in the context of species level assignments of our global collection of isolates and strains obtained from a diverse array of hosts. In addition, this method was compared to an in-house multilocus sequence typing (MLST) method based on polymorphisms in three housekeeping genes, the rrs locus and two envelope proteins. Phylogenetic relationships were deduced based on bifurcating Neighbor-joining trees as well as median joining network analyses integrating both the FAFLP data and MLST based haplotypes. The phylogenetic relationships were also reproduced through Bayesian analysis of the multilocus sequence polymorphisms. We found FAFLP to be an important method for outbreak investigation and for clustering of isolates based on their geographical descent rather than by genome species types. The FAFLP method was, however, not able to convey much taxonomical utility sufficient to replace the highly tedious serotyping procedures in vogue. MLST, on the other hand, was found to be highly robust and efficient in identifying ancestral relationships and segregating the outbreak associated strains or otherwise according to their genome species status and, therefore, could unambiguously be applied for investigating phylogenetics of Leptospira in the context of taxonomy as well as gene flow. For instance, MLST was more efficient, as compared to FAFLP method, in clustering strains from the Andaman island of India, with their counterparts from mainland India and Sri Lanka, implying that such strains share genetic relationships and that leptospiral strains might be frequently circulating between the islands and the mainland.
Collapse
Affiliation(s)
- Kishore Nalam
- Pathogen Biology Laboratory, Department of Biotechnology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | | | - Paolo Francalacci
- Department of Zoology and Evolutionary Genetics, University of Sassari, Sassari, Italy
| | - Mumtaz Baig
- Government Vidarbha Institute of Science and Humanities, Amravati, Maharashtra, India
| | - Leonardo A. Sechi
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | - Niyaz Ahmed
- Pathogen Biology Laboratory, Department of Biotechnology, School of Life Sciences, University of Hyderabad, Hyderabad, India
- * E-mail:
| |
Collapse
|
37
|
Houwers DJ, Goris MGA, Abdoel T, Kas JA, Knobbe SS, van Dongen AM, Westerduin FE, Klein WR, Hartskeerl RA. Agglutinating antibodies against pathogenic Leptospira in healthy dogs and horses indicate common exposure and regular occurrence of subclinical infections. Vet Microbiol 2010; 148:449-51. [PMID: 20863632 DOI: 10.1016/j.vetmic.2010.08.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 08/16/2010] [Indexed: 11/26/2022]
|
38
|
Abstract
Leptospirosis, a disease that is often under- or misdiagnosed, significantly impacts human health in many parts of the world and generally affects the most vulnerable communities. Obtaining reliable and comparable information about the occurrence of leptospirosis in populations, and detecting changing trends, are critical for setting policy and public health priorities. Traditional sources of information about the descriptive epidemiology, the disability attributed to leptospirosis infection, and associated risk factors are generally incomplete, fragmented and of uncertain reliability and comparability. Therefore, the global burden of disease concept and methodological framework will be used by the World Health Organization's (WHO) initiative to estimate the global burden of human leptospirosis. The aim of the initiative is to quantify and compare the health of populations by a summary measure of both mortality and disability, the disability-adjusted life year (DALY). WHO has established the Leptospirosis Burden Epidemiology Reference Group (LERG) to coordinate the assessment. The burden estimates provided by the LERG will guide public health policy on leptospirosis disease control and prevention, with the aim of reducing the impact on human health.
Collapse
Affiliation(s)
- Bernadette Abela-Ridder
- Department of Food Safety and Zoonoses, Health Security and Environment, World Health Organization, Geneva, Switzerland.
| | | | | |
Collapse
|
39
|
Ahmed A, Anthony RM, Hartskeerl RA. A simple and rapid molecular method for Leptospira species identification. Infect Genet Evol 2010; 10:955-62. [PMID: 20547247 DOI: 10.1016/j.meegid.2010.06.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 05/28/2010] [Accepted: 06/02/2010] [Indexed: 11/30/2022]
Abstract
Serological and DNA-based classification systems only have little correlation. Currently serological and molecular methods for characterizing Leptospira are complex and costly restricting their world-wide distribution and use. Ligation mediated amplification combined with microarray analysis avoids many of these drawbacks. We demonstrated that this approach used in the Check-Points (CP) assay can successfully applied for the generic detection of Leptospira and can discriminate between saprophytic, intermediate and pathogenic species. In addition, the CP assay could unambiguously detect strains of seven pathogenic species and revealed discrepancies in previous speciation and culture collections. The method provides a valuable tool adding to the molecular study of leptospires and their local and global distribution.
Collapse
Affiliation(s)
- Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Meibergdreef 39, 1105 AZ Amsterdam, The Netherlands
| | | | | |
Collapse
|
40
|
Cerqueira GM, McBride AJA, Queiroz A, Pinto LS, Silva EF, Hartskeerl RA, Reis MG, Ko AI, Dellagostin OA. Monitoring Leptospira strain collections: the need for quality control. Am J Trop Med Hyg 2010; 82:83-7. [PMID: 20065000 PMCID: PMC2803514 DOI: 10.4269/ajtmh.2010.09-0558] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 10/26/2009] [Indexed: 11/07/2022] Open
Abstract
The purpose of this study was to perform a 16S sequence-based quality control of two Leptospira strain collections. 16S rRNA gene sequencing was used to verify two Leptospira reference collections provided by the World Health Organization and maintained at a reference laboratory for leptospirosis in Brazil. Among the 89 serovars evaluated, four conflicting strains were identified in one of the collections. Although 16S rRNA gene sequencing cannot identify Leptospira beyond the species level, it is suitable for the identification of contamination and quality control of leptospiral reference collections. This study highlights the importance of the availability of high-quality 16S rRNA sequences in public databases. In addition, it emphasizes the need for periodical verifications and quality control of Leptospira reference collections.
Collapse
|
41
|
Wagenaar JFP, Goris MGA, Partiningrum DL, Isbandrio B, Hartskeerl RA, Brandjes DPM, Meijers JCM, Gasem MH, van Gorp ECM. Coagulation disorders in patients with severe leptospirosis are associated with severe bleeding and mortality. Trop Med Int Health 2009; 15:152-9. [PMID: 20002620 DOI: 10.1111/j.1365-3156.2009.02434.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To determine the involvement of coagulation in bleeding and poor outcome in patients with severe leptospirosis. METHODS In a prospective study, parameters of the coagulation system were measured on admission and during follow-up in 52 consecutive patients with severe leptospirosis. RESULTS All patients showed coagulation disorders, such as prolonged prothrombin time (PT) and activated partial thromboplastin time, marked procoagulant activity [thrombin-antithrombin (TAT) complexes, prothrombin fragment 1+2, D-dimer], reduced levels of anticoagulant markers (protein C, antithrombin) and increased (anti-) fibrinolytic activity [plasmin-antiplasmin (PAP) complexes, plasminogen activator inhibitor-1]. These disorders were more pronounced in patients who died eventually. PT prolongation was associated with mortality (OR 1.4, 95% CI: 1.0-1.8, P = 0.04). Bleeding occurred in 31 subjects (60%). Of these, 24 had mild bleeding and seven had severe haemorrhages. Thrombocytopenia (platelets </=100 x 10(9)/l) was significantly associated with clinical bleeding (OR 4.6, 95% CI: 1.3-16). A subanalysis of patients with and without severe bleeding revealed a more pronounced imbalance of the coagulation system in patients with severe bleeding, as reflected by a significant association with PT (OR 1.4, 95% CI: 1.0-1.8, P = 0.05) and the TAT/PAP ratio (OR 1.3, 95% CI: 1.0-1.6, P = 0.05), which is an indicator of the balance between coagulation and fibrinolysis. Overt disseminated intravascular coagulation (DIC) was found in 10 (22%) of the 46 patients for whom the score could be calculated. There was no significant association between DIC scores, bleeding diathesis or poor outcome. CONCLUSION The coagulation system was strongly activated in patients with leptospirosis. This was more pronounced in the deceased and in patients with severe bleeding than in than the survivors and in those without severe bleeding.
Collapse
Affiliation(s)
- J F P Wagenaar
- Department of Internal Medicine, Slotervaart Hospital, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Ahmed A, Engelberts MFM, Boer KR, Ahmed N, Hartskeerl RA. Development and validation of a real-time PCR for detection of pathogenic leptospira species in clinical materials. PLoS One 2009; 4:e7093. [PMID: 19763264 PMCID: PMC2740861 DOI: 10.1371/journal.pone.0007093] [Citation(s) in RCA: 171] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Accepted: 08/11/2009] [Indexed: 11/25/2022] Open
Abstract
Available serological diagnostics do not allow the confirmation of clinically suspected leptospirosis at the early acute phase of illness. Several conventional and real-time PCRs for the early diagnosis of leptospirosis have been described but these have been incompletely evaluated. We developed a SYBR Green-based real-time PCR targeting secY and validated it according to international guidelines. To determine the analytical specificity, DNA from 56 Leptospira strains belonging to pathogenic, non-pathogenic and intermediate Leptospira spp. as well as 46 other micro-organisms was included in this study. All the pathogenic Leptospira gave a positive reaction. We found no cross-reaction with saprophytic Leptospira and other micro-organisms, implying a high analytical specificity. The analytical sensitivity of the PCR was one copy per reaction from cultured homologous strain M 20 and 1.2 and 1.5 copy for heterologous strains 1342 K and Sarmin, respectively. In spiked serum & blood and kidney tissue the sensitivity was 10 and 20 copies for M 20, 15 and 30 copies for 1342 K and 30 and 50 copies for Sarmin. To determine the diagnostic sensitivity (DSe) and specificity (DSp), clinical blood samples from 26 laboratory-confirmed and 107 negative patients suspected of leptospirosis were enrolled as a prospective consecutive cohort. Based on culture as the gold standard, we found a DSe and DSp of 100% and 93%, respectively. All eight PCR positive samples that had a negative culture seroconverted later on, implying a higher actual DSp. When using culture and serology as the gold standard, the DSe was lower (89%) while the DSp was higher (100%). DSe was 100% in samples collected within the first – for treatment important - 4 days after onset of the illness. Reproducibility and repeatability of the assay, determined by blind testing kidney samples from 20 confirmed positive and 20 negative rodents both appeared 100%. In conclusion we have described for the first time the development of a robust SYBR Green real-time PCR for the detection of pathogenic Leptospira combined with a detailed assessment of its clinical accuracy, thus providing a method for the early diagnosis of leptospirosis with a well-defined satisfactory performance.
Collapse
Affiliation(s)
- Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis and Section of Epidemiology, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | - Mirjam F. M. Engelberts
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis and Section of Epidemiology, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | - Kimberly R. Boer
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis and Section of Epidemiology, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | - Niyaz Ahmed
- Pathogen Biology Laboratory, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis and Section of Epidemiology, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
- * E-mail:
| |
Collapse
|
43
|
Gasem MH, Wagenaar JFP, Goris MGA, Adi MS, Isbandrio BB, Hartskeerl RA, Rolain JM, Raoult D, van Gorp ECM. Murine typhus and leptospirosis as causes of acute undifferentiated fever, Indonesia. Emerg Infect Dis 2009; 15:975-7. [PMID: 19523308 PMCID: PMC2727336 DOI: 10.3201/eid1506.081405] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
To investigate rickettsioses and leptospirosis among urban residents of Semarang, Indonesia, we tested the blood of 137 patients with fever. Evidence of Rickettsia typhi, the agent of murine typhus, was found in 9 patients. Another 9 patients showed inconclusive serologic results. Thirteen patients received a diagnosis of leptospirosis. No dual infections were detected.
Collapse
|
44
|
Wagenaar JFP, Gasem MH, Goris MGA, Leeflang M, Hartskeerl RA, van der Poll T, van 't Veer C, van Gorp ECM. Soluble ST2 levels are associated with bleeding in patients with severe Leptospirosis. PLoS Negl Trop Dis 2009; 3:e453. [PMID: 19488407 PMCID: PMC2684584 DOI: 10.1371/journal.pntd.0000453] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Accepted: 05/06/2009] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Severe leptospirosis features bleeding and multi-organ failure, leading to shock and death. Currently it is assumed that both exaggerated inflammation and immune suppression contribute to mortality in sepsis. Indeed, several proinflammatory cytokines are reported to be induced during leptospirosis. Toll-like receptors, which play an important role in the initiation of an innate immune response, are inhibited by negative regulators including the membrane-bound ST2 (mST2) receptor. Soluble ST2 (sST2) has been implicated to inhibit signaling through mST2. The aim of this study was to determine the extent of sST2 and (pro-) inflammatory cytokine release in patients with severe leptospirosis. METHODOLOGY AND PRINCIPAL FINDINGS In an observational study, 68 consecutive cases of severe leptospirosis were included. Soluble ST2 and cytokines (TNF-alpha, IL-1beta, IL-6, IL-8, and IL-10) were repeatedly measured. To determine whether blood cells are a source of sST2 during infection, we undertook an in vitro experiment: human whole blood and peripheral blood mononuclear cells (PBMC) were stimulated with viable pathogenic Leptospira. All patients showed elevated sST2, IL-6, IL-8, and IL-10 levels on admission. Admission sST2 levels correlated with IL-6, IL-8, and IL-10. Thirty-four patients (50%) showed clinical bleeding. Soluble ST2 levels were significantly associated with bleeding overall (OR 2.0; 95%CI: 1.2-3.6) and severe bleeding (OR 5.1; 95%CI: 1.1-23.8). This association was unique, since none of the cytokines showed this correlation. Moreover, sST2 was associated with mortality (OR 2.4; 95%CI: 1.0-5.8). When either whole blood or isolated PBMCs were stimulated with Leptospira in vitro, no sST2 production could be detected. CONCLUSIONS Patients with severe leptospirosis demonstrated elevated plasma sST2 levels. Soluble ST2 levels were associated with bleeding and mortality. In vitro experiments showed that (white) blood cells are probably not the source. In this regard, sST2 could be an indicative marker for tissue damage in patients suffering from severe leptospirosis.
Collapse
Affiliation(s)
- Jiri F P Wagenaar
- Department of Internal Medicine, Slotervaart Hospital, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Wagenaar JF, Goris MG, Gasem MH, Isbandrio B, Moalli F, Mantovani A, Boer KR, Hartskeerl RA, Garlanda C, van Gorp EC. Long pentraxin PTX3 is associated with mortality and disease severity in severe Leptospirosis. J Infect 2009; 58:425-32. [DOI: 10.1016/j.jinf.2009.04.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 03/26/2009] [Accepted: 04/06/2009] [Indexed: 10/20/2022]
|
46
|
Houwers DJ, Wagenaar JA, Hartskeerl RA, Hautvast JLA, Stinis HPJ, Ruijs WLM, Lenaers SJMM. [Leptospirosis (Weil disease) in a dog: a risk for people?]. Tijdschr Diergeneeskd 2009; 134:392-394. [PMID: 19480146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- D J Houwers
- Departement Infectieziekten en Immunologie, Faculteit Diergeneeskunde, Universiteit Utrecht
| | | | | | | | | | | | | |
Collapse
|
47
|
Faria MTD, Calderwood MS, Athanazio DA, McBride AJ, Hartskeerl RA, Pereira MM, Ko AI, Reis MG. Carriage of Leptospira interrogans among domestic rats from an urban setting highly endemic for leptospirosis in Brazil. Acta Trop 2008; 108:1-5. [PMID: 18721789 DOI: 10.1016/j.actatropica.2008.07.005] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Revised: 06/17/2008] [Accepted: 07/21/2008] [Indexed: 10/21/2022]
Abstract
A survey was conducted to identify reservoirs for urban leptospirosis in the city of Salvador, Brazil. Sampling protocols were performed in the vicinity of households of severe leptospirosis cases identified during active hospital-based surveillance. Among a total of 142 captured Rattus norvegicus (Norwegian brown rat), 80.3% had a positive culture isolate from urine or kidney specimens and 68.1% had a positive serum sample by microscopic agglutination test (MAT) titre of > or = 1:100. Monoclonal antibody-based typing of isolates identified that the agent carried by rats was Leptospira interrogans serovar Copenhageni, which was the same serovar isolated from patients during hospital-based surveillance. Leptospira spp. were not isolated from 8 captured Didelphis marsupialis (Opossum), while 5/7 had a positive MAT titre against a saprophytic serogroup. R. rattus were not captured during the survey. The study findings indicate that the brown rat is a major rodent reservoir for leptospirosis in this urban setting. Furthermore, the high carriage rates of L. interrogans serovar Copenhageni in captured rats suggest that there is a significant degree of environmental contamination with this agent in the household environment of high risk areas, which in turn is a cause of transmission during urban epidemics.
Collapse
|
48
|
Victoria B, Ahmed A, Zuerner RL, Ahmed N, Bulach DM, Quinteiro J, Hartskeerl RA. Conservation of the S10-spc-alpha locus within otherwise highly plastic genomes provides phylogenetic insight into the genus Leptospira. PLoS One 2008; 3:e2752. [PMID: 18648538 PMCID: PMC2481283 DOI: 10.1371/journal.pone.0002752] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Accepted: 06/24/2008] [Indexed: 11/21/2022] Open
Abstract
S10-spc-α is a 17.5 kb cluster of 32 genes encoding ribosomal proteins. This locus has an unusual composition and organization in Leptospira interrogans. We demonstrate the highly conserved nature of this region among diverse Leptospira and show its utility as a phylogenetically informative region. Comparative analyses were performed by PCR using primer sets covering the whole locus. Correctly sized fragments were obtained by PCR from all L. interrogans strains tested for each primer set indicating that this locus is well conserved in this species. Few differences were detected in amplification profiles between different pathogenic species, indicating that the S10-spc-α locus is conserved among pathogenic Leptospira. In contrast, PCR analysis of this locus using DNA from saprophytic Leptospira species and species with an intermediate pathogenic capacity generated varied results. Sequence alignment of the S10-spc-α locus from two pathogenic species, L. interrogans and L. borgpetersenii, with the corresponding locus from the saprophyte L. biflexa serovar Patoc showed that genetic organization of this locus is well conserved within Leptospira. Multilocus sequence typing (MLST) of four conserved regions resulted in the construction of well-defined phylogenetic trees that help resolve questions about the interrelationships of pathogenic Leptospira. Based on the results of secY sequence analysis, we found that reliable species identification of pathogenic Leptospira is possible by comparative analysis of a 245 bp region commonly used as a target for diagnostic PCR for leptospirosis. Comparative analysis of Leptospira strains revealed that strain H6 previously classified as L. inadai actually belongs to the pathogenic species L. interrogans and that L. meyeri strain ICF phylogenetically co-localized with the pathogenic clusters. These findings demonstrate that the S10-spc-α locus is highly conserved throughout the genus and may be more useful in comparing evolution of the genus than loci studied previously.
Collapse
Affiliation(s)
- Berta Victoria
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Santiago de Compostela, Galicia, Spain
| | - Ahmed Ahmed
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
| | - Richard L. Zuerner
- Bacterial Diseases of Livestock Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, Iowa, United States of America
| | - Niyaz Ahmed
- Pathogen Evolution Laboratory, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India
| | - Dieter M. Bulach
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Javier Quinteiro
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Santiago de Compostela, Galicia, Spain
| | - Rudy A. Hartskeerl
- WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
- * E-mail:
| |
Collapse
|
49
|
Priya CG, Hoogendijk KT, Berg M, Rathinam SR, Ahmed A, Muthukkaruppan VR, Hartskeerl RA. Field rats form a major infection source of leptospirosis in and around Madurai, India. J Postgrad Med 2008; 53:236-40. [PMID: 18097111 DOI: 10.4103/0022-3859.37511] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
AIMS To determine the seroprevalence of leptospires and to isolate Leptospira spp. from field rats and bandicoots in and around Madurai. MATERIALS AND METHODS Thirteen rats and five bandicoots were trapped alive from fields in and around Madurai. Blood samples were tested for anti-leptospiral antibodies by microscopic agglutination test while the urine and kidney samples were used for isolation of leptospires. The isolated leptospires were tested for pathogenic status (13 degrees C test and PCR) followed by serological and genetic characterization. RESULTS Serology revealed the presence of anti-leptospiral antibodies in 58% (7/12) of field rats and leptospires were isolated from two urine and six kidney samples. The bandicoots were negative in both serology and culture. Analysis of the isolates from field rats revealed that all the isolates were pathogenic except for one, which was further confirmed by serological and genetic characterization. Six of the seven pathogenic isolates were identified as L. interrogans serogroup Autumnalis serovar Akiyami A and one as L. borgpetersenii serogroup Javanica serovar Veldrat Batavia 46. CONCLUSIONS Serology and isolation reveals that field rats are major natural carriers and shedders of leptospires in and around Madurai.
Collapse
Affiliation(s)
- C G Priya
- Department of Immunology, Aravind Medical Research Foundation, No.1, Anna Nagar, Madurai - 625 020, Tamil Nadu, India
| | | | | | | | | | | | | |
Collapse
|
50
|
Thai KTD, Nga TTT, Phuong HL, Giao PT, Hung LQ, Binh TQ, Van Nam N, Hartskeerl RA, de Vries PJ. Seroepidemiology and serological follow-up of anti-leptospiral IgG in children in Southern Vietnam. Acta Trop 2008; 106:128-31. [PMID: 18395178 DOI: 10.1016/j.actatropica.2008.02.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 02/18/2008] [Accepted: 02/25/2008] [Indexed: 11/19/2022]
Abstract
A follow-up study was conducted with 23 months interval to investigate the seroepidemiology and persistence of Leptospira IgG antibodies among healthy children in Binh Thuan province, Southern Vietnam. Sera from 262 children (7-13 years of age) were collected and analysed with a commercially available enzyme-linked immunosorbent assay (ELISA) for Leptospira IgG. Seroconversion was observed in 10.4% (22 of 211, 95% CI: 5.6-26.7) of the children, of whom 18 (8.5%) had probably and four (1.9%) had certainly been exposed to Leptospira. Based on the reduction of sero-negatives of 1.9% among children who have been certainly exposed, the annual seroconversion rate, a measure of the incidence rate of Leptospira infections, corresponds to 0.99% (95% CI: 0.39-2.52). In 61% (31 of 51, 95% CI: 47.1-73.0) of the children with past-infection, Leptospira IgG antibodies remain detectable after 2 years. Data from this study indicate that IgG antibody responses against Leptospira may persist at least for 2 years in children without manifestations of leptospirosis. Results of study uncover the true incidence of leptospirosis infection, the dynamics of waxing and waning antibody concentrations and points at a larger burden of clinically non-significant Leptospira infections in Southern Vietnam. This also indicates background reactivity for serological testing and thus serological result of a single serum sample must be carefully interpreted.
Collapse
Affiliation(s)
- Khoa T D Thai
- Division of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Center, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | |
Collapse
|