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Cardoso TL, de Freitas SB, Seixas Neto ACP, Balassiano IT, Hartwig DD. Advancing serologic diagnosis: assessing the efficacy of rErpY-like protein in human leptospirosis detection. Braz J Microbiol 2024:10.1007/s42770-024-01364-4. [PMID: 38805148 DOI: 10.1007/s42770-024-01364-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/29/2024] [Indexed: 05/29/2024] Open
Abstract
Leptospirosis is a globally distributed infectious disease caused by pathogenic spirochetes of the Leptospira genus, often overlooked. It is estimated that the disease affects approximately one million people annually, resulting in more than 58,900 deaths. The gold standard for serodiagnosis of leptospirosis is the Microscopic Agglutination Test (MAT). However, the limitations of this technique necessitate the exploration of alternative diagnostic methods. In this study, we evaluated the ErpY-like recombinant protein (rErpY-like) in the development of a serologic diagnostic assay for human leptospirosis. Eighty-six human sera samples, characterized by MAT, underwent evaluation through indirect IgM-ELISA and IgG-ELISA. The sensitivity and specificity values obtained from IgM-ELISA were 60% and 76%, respectively, while those from IgG-ELISA were 96.4% and 100%, respectively. The use of the rErpY-like protein in both IgM-ELISA and IgG-ELISA proves to be a sensitive and specific method for antibody detection. This could potentially serve as a valuable alternative tool in the diagnosis of human leptospirosis.
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Affiliation(s)
- Thayná Laner Cardoso
- Laboratory of Bacteriology and Bioassays, Department of Microbiology and Parasitology, Institute of Biology, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Stella Buchhorn de Freitas
- Laboratory of Bacteriology and Bioassays, Department of Microbiology and Parasitology, Institute of Biology, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Amilton Clair Pinto Seixas Neto
- Laboratory of Bacteriology and Bioassays, Department of Microbiology and Parasitology, Institute of Biology, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Ilana Teruszkin Balassiano
- Bacterial Zoonoses Laboratory, Leptospirosis National Reference Center/Leptospira Collection, WHO/PAHO Collaborating Center for Leptospirosis, Department of Bacteriology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil
| | - Daiane Drawanz Hartwig
- Laboratory of Bacteriology and Bioassays, Department of Microbiology and Parasitology, Institute of Biology, Federal University of Pelotas, Pelotas, RS, Brazil.
- Federal University of Pelotas, University Campus, Pelotas, RS, CEP 96010-900, Brazil.
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Suwannin P, Jangpatarapongsa K, Polpanich D, Alhibshi A, Errachid A, Elaissari A. Enhancing leptospirosis control with nanosensing technology: A critical analysis. Comp Immunol Microbiol Infect Dis 2024; 104:102092. [PMID: 37992537 DOI: 10.1016/j.cimid.2023.102092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 11/24/2023]
Abstract
Leptospirosis is a serious health problem in tropical areas; thus, animals shed leptospires in the environment. Humans are accidental hosts infected through exposure to contaminating bacteria in the environment. One health strategy can be applied to protect and eliminate leptospirosis because this cooperates and coordinates activities between doctors, veterinarians, and ecologists. However, conventional methods still have limitations. Therefore, the main challenges of leptospirosis control are the high sensing of detection methods to screen and control the pathogens. Interestingly, nano sensing combined with a leptospirosis detection approach can increase the sensitivity and eliminate some limitations. This article reviews nanomaterial development for an advanced leptospirosis detection method, e.g., latex beads-based agglutination test, magnetic nanoparticles enrichment, and gold-nanoparticles-based immunochromatographic assay. Thus, nanomaterials can be functionalized with biomolecules or sensing molecules utilized in various mechanisms such as biosensors. Over the last decade, many biosensors have been developed for Leptospira spp. pathogen and others. The evolution of biosensors for leptospirosis detection was designed for high efficiency and might be an alternative tool. In addition, the high-sensing fabrications are useful for leptospires screening in very low levels, for example, soil or water from the environment.
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Affiliation(s)
- Patcharapan Suwannin
- Center for Research Innovation and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand; Univ Lyon, University Claude Bernard Lyon-1, CNRS, ISA-UMR 5280, Villeurbanne 69622, France
| | - Kulachart Jangpatarapongsa
- Center for Research Innovation and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand
| | - Duangporn Polpanich
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani 12120, Thailand
| | - Amani Alhibshi
- Department of Neuroscience Research, Institute of Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Abdelhamid Errachid
- Univ Lyon, University Claude Bernard Lyon-1, CNRS, ISA-UMR 5280, Villeurbanne 69622, France
| | - Abdelhamid Elaissari
- Univ Lyon, University Claude Bernard Lyon-1, CNRS, ISA-UMR 5280, Villeurbanne 69622, France.
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Hailat NQ, Mafrag ZA, Gharaibeh MH, Alzuheir IM. Pathological and molecular study of kidneys in apparently healthy cattle and sheep with special reference to Leptospira species in central and northern Jordan. Vet World 2023; 16:2488-2496. [PMID: 38328369 PMCID: PMC10844780 DOI: 10.14202/vetworld.2023.2488-2496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Accepted: 11/13/2023] [Indexed: 02/09/2024] Open
Abstract
Background and Aim Renal pathological conditions can cause significant economic losses for livestock owners. This study investigated and described the gross pathology and histopathology of lesions found in the kidneys of sheep and cattle, with particular attention to the presence of Leptospira spp. Materials and Methods Three hundred and sixty kidneys from apparently healthy sheep and cattle (208 and 152, respectively) were collected from slaughterhouses in Jordan for gross and histopathological examinations, multiplex polymerase chain reaction (PCR) analysis, and gene sequencing of Leptospira spp. Results Histopathological analysis of the samples revealed the following conditions: interstitial nephritis (4.44%), glomerulonephritis (4.16%), acute tubular necrosis (17.22%), and renal congestion (4.72%). In addition, in 26.9% of the samples, hyaline material was observed in the interstitium of the cortex and medulla. The PCR results revealed that 83 (23.1%) of the 360 samples were positive for Leptospira spp. 16S rRNA, 42/152 (28%) of cattle, and 41/208 (20%) of sheep. Four samples (two sheep and two cattle) were sequenced and deposited in GenBank with accession numbers from OL701310 to OL701313. Basic Local Alignment Search Tool search and nucleotide similarities between OL701311 and OL701313 resulted in the highest similarities with different Leptospira borgpetersenii strains, whereas OL701310 showed the highest nucleotide similarity (99.2%) with the Leptospira interrogans strain. Similarly, phylogenetic analysis revealed that OL701311 to OL701313 clustered together with different serovars of L. borgpetersenii, whereas OL701310 clustered with the L. interrogans clade. Conclusion This is the first study to reveal a close association between pathogenic Leptospira spp. and kidney disorders in Jordanian cattle and sheep. These findings may help expand the current understanding of the causes and mechanisms of renal disease in cattle and sheep and contribute to developing more effective prevention and treatment programs.
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Affiliation(s)
- Nabil Q. Hailat
- Department of Veterinary Pathology and Public Health Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030 Irbid, 22110 Jordan
| | - Zaid A. Mafrag
- Department of Veterinary Pathology and Public Health Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030 Irbid, 22110 Jordan
| | - Mohammad H. Gharaibeh
- Department of Basic Veterinary Medical Science, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030 Irbid, 22110 Jordan
| | - Ibrahim M. Alzuheir
- Department of Veterinary Medicine, Faculty of Agriculture and Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
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Bradley EA, Lockaby G. Leptospirosis and the Environment: A Review and Future Directions. Pathogens 2023; 12:1167. [PMID: 37764975 PMCID: PMC10538202 DOI: 10.3390/pathogens12091167] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 08/31/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Leptospirosis is a zoonotic disease of global importance with significant morbidity and mortality. However, the disease is frequently overlooked and underdiagnosed, leading to uncertainty of the true scale and severity of the disease. A neglected tropical disease, leptospirosis disproportionately impacts disadvantaged socioeconomic communities most vulnerable to outbreaks of zoonotic disease, due to contact with infectious animals and contaminated soils and waters. With growing evidence that Leptospira survives, persists, and reproduces in the environment, this paper reviews the current understanding of the pathogen in the environment and highlights the unknowns that are most important for future study. Through a systematic Boolean review of the literature, our study finds that detailed field-based study of Leptospira prevalence, survival, and transmission in natural waters and soils is lacking from the current literature. This review identified a strong need for assessment of physical characteristics and biogeochemical processes that support long-term viability of Leptospira in the environment followed by epidemiological assessment of the transmission and movement of the same strains of Leptospira in the present wildlife and livestock as the first steps in improving our understanding of the environmental stage of the leptospirosis transmission cycle.
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Affiliation(s)
- Elizabeth A. Bradley
- College of Forestry, Wildlife, and Environment, Auburn University, Auburn, AL 36849, USA
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Parra Barrera EL, Bello Piruccini S, Rodríguez K, Duarte C, Torres M, Undurraga EA. Demographic and clinical risk factors associated with severity of lab-confirmed human leptospirosis in Colombia, 2015-2020. PLoS Negl Trop Dis 2023; 17:e0011454. [PMID: 37406001 DOI: 10.1371/journal.pntd.0011454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 06/09/2023] [Indexed: 07/07/2023] Open
Abstract
BACKGROUND Leptospirosis is a common zoonoses and is a major global public health threat. Most cases are mild, typically presenting as a non-specific acute febrile illness. However, leptospirosis can have life-threatening manifestations, including pulmonary hemorrhage syndrome, and acute kidney injury. In Colombia, notification and lab-confirmation of suspected human cases are mandatory. However, little is known about the demographic and clinical factors associated with severe leptospirosis, which could help to reduce clinical complications and mortality. Our aim was to identify risk factors associated with severe leptospirosis, intensive care unit (ICU) admission, and mortality in lab-confirmed cases in Colombia, 2015-2020. METHODS AND FINDINGS We analyzed 201 lab-confirmed human leptospirosis cases by microagglutination test. We used a logistic regression to identify the demographic and clinical risk factors associated with severe leptospirosis, admission to ICU, and death. Most leptospirosis confirmed cases occurred in men (85.6%); the mean age was 36.7 years. We classified severe cases (43.3%) by clinical manifestations as renal (29.9%) and liver (27.4%) failure, multiple-organ failure (24.4%), septic shock (24.4%), Weil syndrome (18.4%), pulmonary hemorrhage (18.4%), and meningitis (2.5%), admitted to the ICU (30.3%), and fatal (8.5%). Clinical conditions associated with severe leptospirosis were dyspnea (OR: 5.54; 95% CI: 1.46 to 20.98), tachycardia (OR:9.69; 95% CI: 15.96 to 58.8), and rash (OR: 10.25; 95% CI: 25.01 to 42.08). CONCLUSIONS We identified demographic characteristics and clinical symptoms associated with severe leptospirosis in Colombia. We hope these results can support clinicians in providing timely treatment to leptospirosis patients to avoid preventable medical complications or deaths.
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Affiliation(s)
- Eliana L Parra Barrera
- Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile
- Multidisciplinary Initiative for Collaborative Research on Bacterial Pathogens and Resistance (MICROB-R), Santiago, RM Chile
- Grupo de Virología, Instituto Nacional de Salud, Bogotá, Colombia
| | | | - Karina Rodríguez
- Grupo de Microbiología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Carolina Duarte
- Grupo de Microbiología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Marisa Torres
- Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile
| | - Eduardo A Undurraga
- Multidisciplinary Initiative for Collaborative Research on Bacterial Pathogens and Resistance (MICROB-R), Santiago, RM Chile
- Escuela de Gobierno, Pontificia Universidad Católica de Chile, Santiago, RM, Chile
- CIFAR Azrieli Global Scholars program, CIFAR, Toronto, Canada
- Research Center for Integrated Disaster Risk Management (CIGIDEN), Santiago, RM Chile
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Bressan CDS, Teixeira MDLB, Gouvêa MIFDS, de Pina-Costa A, Santos HFP, Calvet GA, Lupi O, Siqueira AM, Valls-de-Souza R, Valim C, Brasil P. Challenges of acute febrile illness diagnosis in a national infectious diseases center in Rio de Janeiro: 16-year experience of syndromic surveillance. PLoS Negl Trop Dis 2023; 17:e0011232. [PMID: 37011087 PMCID: PMC10101631 DOI: 10.1371/journal.pntd.0011232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 04/13/2023] [Accepted: 03/10/2023] [Indexed: 04/05/2023] Open
Abstract
INTRODUCTION Acute febrile illnesses (AFI) are a frequent chief complaint in outpatients. Because the capacity to investigate the causative pathogen of AFIs is limited in low- and middle-income countries, patient management may be suboptimal. Understanding the distribution of causes of AFI can improve patient outcomes. This study aims to describe the most common etiologies diagnosed over a 16-years period in a national reference center for tropical diseases in a large urban center in Rio de Janeiro, Brazil. METHODS From August 2004-December 2019, 3591 patients > 12 years old, with AFI and/or rash were eligible. Complementary exams for etiological investigation were requested using syndromic classification as a decision guide. Results. Among the 3591 patients included, endemic arboviruses such as chikungunya (21%), dengue (15%) and zika (6%) were the most common laboratory-confirmed diagnosis, together with travel-related malaria (11%). Clinical presumptive diagnosis lacked sensitivity for emerging diseases such as zika (31%). Rickettsia disease and leptospirosis were rarely investigated and an infrequent finding when based purely on clinical features. Respiratory symptoms increased the odds for the diagnostic remaining inconclusive. CONCLUSIONS Numerous patients did not have a conclusive etiologic diagnosis. Since syndromic classification used for standardization of etiological investigation and presumptive clinical diagnosis had moderate accuracy, it is necessary to incorporate new diagnostic technologies to improve diagnostic accuracy and surveillance capacity.
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Affiliation(s)
| | - Maria de Lourdes Benamor Teixeira
- Laboratory of Epidemiology Research and Social Determinants of Health, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Anielle de Pina-Costa
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
- Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | | | - Guilherme Amaral Calvet
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Otilia Lupi
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Andre Machado Siqueira
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rogério Valls-de-Souza
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa Valim
- Department of Global Health, Boston University School of Public Health, Boston, Massachusetts, United States of America
| | - Patrícia Brasil
- Acute Febrile Illnesses Service, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil
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Dharmashekar C, Shreevatsa B, Jain AS, Harendra B, Pradeep S, Vishwanath PM, Singh P, V B, KK V, Patil SS, Shati AA, Alfaifi MY, Elbehairi SEI, Amachawadi RG, Kollur SP, Shivamallu C. Evaluating the Antimicrobial and Anti-Hemolytic Activity of Synthesized Pseudopeptide against Leptospiral Species: In Silico and In Vitro Approach. Molecules 2023; 28:molecules28031106. [PMID: 36770771 PMCID: PMC9920664 DOI: 10.3390/molecules28031106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/09/2023] [Accepted: 01/16/2023] [Indexed: 01/24/2023] Open
Abstract
Bacterial infections are one of the leading causes of morbidity, mortality, and healthcare complications in patients. Leptospirosis is found to be the most prevalent, re-emergent, and neglected tropical zoonotic disease worldwide. The adaptation to various environmental conditions has made Leptospira acquire a large genome (~4.6 Mb) and a complex outer membrane, making it unique among bacteria that mimic the symptoms of jaundice and hemorrhage. Sph2 is another important virulence factor that enhances hemolytic sphingomyelinase-capable of moving inside mitochondria-which increases the ROS level and decreases the mitochondrial membrane potential, thereby leading to cell apoptosis. In the present study, 25 suspected bovine serum samples were subjected to the Microscopic Agglutination Test (MAT) across the Mysuru region. Different samples, such as urine, serum, and aborted materials from the confirmed MAT-positive animals, were used for isolation and genomic detection by conventional PCR targeting virulence gene, Lipl32, using specific primers. Further, in vitro and in silico studies were performed on isolated cultures to assess the anti-leptospiral, anti-hemolytic, and sphingomyelinase enzyme inhibition using novel pseudopeptides. The microdilution technique (MDT) and dark field microscope (DFM) assays revealed that at a concentration of 62.5 μg/mL, the pseudopeptide inhibited 100% of the growth of Leptospira spp., suggesting its efficiency in the treatment of leptospirosis. The flow cytometry analyses show the potency of the pseudopeptide against sphingomyelinase enzymes using human umbilical vein endothelial cells (HUVECs). Thus, the present study demonstrated the efficacy of the pseudopeptide in the inhibition of the growth of Leptospira, and therefore, this can be used as an alternative drug for the treatment of leptospirosis.
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Affiliation(s)
- Chandan Dharmashekar
- Department of Biotechnology and Bioinformatics, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Bhargav Shreevatsa
- Department of Biotechnology and Bioinformatics, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Anisha S. Jain
- Department of Microbiology, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Bhavana Harendra
- Department of Microbiology, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Sushma Pradeep
- Department of Biotechnology and Bioinformatics, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Prashanth M. Vishwanath
- Department of Biochemistry, JSS Academy of Higher Education and Research, Mysuru 570 015, India
| | - Pranav Singh
- Department of Medicine, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Udupi 576 104, India
| | - Balamurugan V
- ICAR, National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru 560 064, India
| | - Vinod KK
- ICAR, National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru 560 064, India
| | - Sharanagouda S. Patil
- ICAR, National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru 560 064, India
| | - Ali A. Shati
- Biology Department, Faculty of Science, King Khalid University, Abha 9004, Saudi Arabia
| | - Mohammad Y. Alfaifi
- Biology Department, Faculty of Science, King Khalid University, Abha 9004, Saudi Arabia
| | - Serag Eldin I. Elbehairi
- Biology Department, Faculty of Science, King Khalid University, Abha 9004, Saudi Arabia
- Cell Culture Lab, Egyptian Organization for Biological Products and Vaccines (VACSERA Holding Company), 51 Wezaret El-Zeraa St., Agouza, Giza 12654, Egypt
| | - Raghavendra G. Amachawadi
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
- Correspondence: (R.G.A.); (S.P.K.); (C.S.)
| | - Shiva Prasad Kollur
- School of Physical Sciences, Amrita Vishwa Vidyapeetham, Mysuru Campus, Mysuru 570 026, India
- Correspondence: (R.G.A.); (S.P.K.); (C.S.)
| | - Chandan Shivamallu
- Department of Biotechnology and Bioinformatics, JSS Academy of Higher Education and Research, Mysuru 570 015, India
- Correspondence: (R.G.A.); (S.P.K.); (C.S.)
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Ntabanganyimana E, Giraneza R, Dusabejambo V, Bizimana A, Hamond C, Iyamuremye A, Nshizirungu P, Uzabakiriho R, Munyengabe M, Wunder EA, Page C. Sero-prevalence of anti-Leptospira antibodies and associated risk factors in rural Rwanda: A cross-sectional study. PLoS Negl Trop Dis 2021; 15:e0009708. [PMID: 34874936 PMCID: PMC8683035 DOI: 10.1371/journal.pntd.0009708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 12/17/2021] [Accepted: 08/05/2021] [Indexed: 11/25/2022] Open
Abstract
Background Leptospirosis is a zoonotic disease transmitted through the urine of wild and domestic animals, and is responsible for over 50,000 deaths each year. In East Africa, prevalence varies greatly, from as low as 7% in Kenya to 37% in Somalia. Transmission epidemiology also varies around the world, with research in Nicaragua showing that rodents are the most clinically important, while studies in Egypt and Chile suggest that dogs may play a more important role. There are no published studies of leptospirosis in Rwanda. Methods & findings We performed a cross-sectional survey of asymptomatic adults recruited from five occupational categories. Serum samples were tested using ELISA and Microscopic Agglutination Test (MAT). We found that 40.1% (151/377) of asymptomatic adults had been exposed to Leptospira spp. Almost 36.3% of positive subjects reported contact with rats (137/377) which represent 90.7% among positive leptospira serology compared with 48.2% of negative subjects (182/377) which represent 80.5% among negative leptospira serology (OR 2.37, CI 1.25–4.49) and 1.7 fold on prevalence ratio and 2.37 of odd ratio. Furthermore, being a crop farmer was significantly associated with leptospirosis (OR 2.06, CI 1.29–3.28). We identified 6 asymptomatic subjects (1.6%) who met criteria for acute infection. Conclusions This study demonstrates a high prevalence of leptospiral antibodies infection among asymptomatic adults in rural Rwanda, particularly relative to neighboring countries. Although positive subjects were more likely to report rat contact, we found no independent association between rats and leptospirosis infection. Nonetheless, exposure was high among crop farmers, which is supportive of the hypothesis that rats together with domestic livestock might contribute to the transmission. Further studies are needed to understand infecting Leptospira servers and elucidate the transmission epidemiology in Rwanda and identify means of host transmitters. Leptospirosis is the most widespread zoonosis in the world, and infections are underappreciated in regions of the world where it may be mistaken for malaria and other tropical illnesses. We performed a seroprevalence study of leptospirosis in healthy asymptomatic adults in Rwanda. Among 377 subjects, we found evidence of infection in 40.1% (151 / 377), which is higher than in neighboring countries such as Kenya (7 to 16%), Tanzania (10 to 15.8%) and Uganda (15%). Our data suggest that leptospirosis may be a common cause of febrile illness in Rwanda, but further studies are needed to differentiate active from asymptomatic.
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Affiliation(s)
- Etienne Ntabanganyimana
- College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.,Gihundwe District Hospital, Rusizi, Rwanda
| | - Robert Giraneza
- College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.,Centre Hospitalier Universitaire de Butare, Huye, Rwanda
| | - Vincent Dusabejambo
- College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda
| | | | - Camila Hamond
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
| | | | | | | | - Marc Munyengabe
- College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.,Ruhango Referral Hospital, Ruhango, Rwanda
| | - Elsio A Wunder
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Cameron Page
- College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.,University Hospital of Brooklyn, SUNY Downstate Medical Center, New York City, New York, United States of America
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Gunasegar S, Neela VK. Evaluation of diagnostic accuracy of loop-mediated isothermal amplification method (LAMP) compared with polymerase chain reaction (PCR) for Leptospira spp. in clinical samples: a systematic review and meta-analysis. Diagn Microbiol Infect Dis 2021; 100:115369. [PMID: 33845305 DOI: 10.1016/j.diagmicrobio.2021.115369] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/20/2021] [Accepted: 03/06/2021] [Indexed: 12/29/2022]
Abstract
Loop-mediated isothermal amplification (LAMP) test is widely used in molecular diagnostics as a point-of-care technique alternative to traditional PCR especially in resource-limited countries. LAMP has been recently used to diagnose leptospirosis. Therefore, we undertook a systematic review and meta-analysis to compare the accuracy of LAMP with PCR in the diagnosis of leptospirosis. Sixty-one studies were extracted from three international databases and analyzed throughout using the PRISMA guideline. The pooled sensitivity of LAMP and PCR technique was 0.80 (95% CI: 0.58-0.90) and 0.54 (95% CI: 0.35-0.67) respectively indicating that LAMP is more sensitive than PCR. The Q* value of LAMP and PCR-based technique is 274.61 and 397.95, respectively. Among the analyzed studies, significant heterogeneity was observed where I2 is 90.90% for LAMP-based and 86.18% for PCR-based. Our study suggests that LAMP has better diagnostic accuracy than PCR. However, future work should be carried out to reduce heterogeneity as well as to improve and develop effective intervention strategies.
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Affiliation(s)
- Shan Gunasegar
- Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Vasantha Kumari Neela
- Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
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Flores B, Escobar K, Muzquiz JL, Sheleby-Elías J, Mora B, Roque E, Torres D, Chávez Á, Jirón W. Detection of Pathogenic Leptospires in Water and Soil in Areas Endemic to Leptospirosis in Nicaragua. Trop Med Infect Dis 2020; 5:tropicalmed5030149. [PMID: 32962119 PMCID: PMC7559144 DOI: 10.3390/tropicalmed5030149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022] Open
Abstract
In Nicaragua, there are ideal environmental conditions for leptospirosis. The objective of this investigation was to detect pathogenic and saprophytic leptospires in water and soil samples from leptospirosis-endemic areas in Nicaragua. Seventy-eight water and 42 soil samples were collected from houses and rivers close to confirmed human cases. Leptospira spp was isolated in Ellinghausen–McCullough–Johnson–Harris (EMJH) culture medium with 5-fluororacil and positive samples were analyzed through PCR for the LipL32 gene, specific for pathogenic leptospires (P1 clade). There were 73 positive cultures from 120 samples, however only six of these (5% of all collected samples) were confirmed to be pathogenic, based on the presence of the LipL32 gene (P1 clade). Of these six pathogenic isolates, four were from Leon and two from Chinandega. Four pathogenic isolates were obtained from water and two from soil. This study proved the contamination of water and soil with pathogenic leptospires, which represents a potential risk for public health.
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Affiliation(s)
- Byron Flores
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
- Correspondence: ; Tel.: +505-8527-0294; Fax: +505-2311-5013
| | - Karla Escobar
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
| | - José Luis Muzquiz
- Department of Animal Pathology, Faculty of Veterinary Sciences, Universidad de Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain;
| | - Jessica Sheleby-Elías
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
| | - Brenda Mora
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
| | - Edipcia Roque
- Research Centre on Health, Work and Environment (CISTA), National Autonomous University of Nicaragua, León 21000 (UNAN-León), Nicaragua;
| | - Dayana Torres
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
| | - Álvaro Chávez
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
- Animal Welfare Department, School of Agricultural Sciences, Catholic University of the Dry Tropic (UCATSE), Estelí 31000, Nicaragua
| | - William Jirón
- Centro Veterinario de Diagnóstico e Investigación (CEVEDI), Departamento de Veterinaria y Zootecnia, Escuela de Ciencias Agrarias y Veterinarias, Universidad Nacional Autónoma de Nicaragua-León (UNAN-León), Carretera a La Ceiba 1 Km al Este, León 21000, Nicaragua; (K.E.); (J.S.-E.); (B.M.); (D.T.); (Á.C.); (W.J.)
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11
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Philip N, Affendy NB, Masri SN, Yuhana MY, Than LTL, Sekawi Z, Neela VK. Combined PCR and MAT improves the early diagnosis of the biphasic illness leptospirosis. PLoS One 2020; 15:e0239069. [PMID: 32915919 PMCID: PMC7485768 DOI: 10.1371/journal.pone.0239069] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 08/30/2020] [Indexed: 02/07/2023] Open
Abstract
The diagnosis of leptospirosis remains a challenge due to its non-specific symptoms and the biphasic nature of the illness. A comprehensive diagnosis that includes both molecular (polymerase chain reaction (PCR)) and serology is vital for early detection of leptospirosis and to avoid misdiagnosis. However, not all samples could be subjected to both tests (serology and molecular) due to budget limitation, infrastructure, and technical expertise at least in resource-limited countries. We evaluated the usefulness of testing the clinically suspected leptospirosis cases with both techniques on all samples collected from the patients on the day of admission. Among the 165 patient’s blood/serum samples tested (from three hospitals in Central Malaysia), 43 (26%) showed positivity by microscopic agglutination test (MAT), 63 (38%) by PCR, while 14 (8%) were positive by both MAT and PCR. For PCR, we tested two molecular targets (lipL32 by qPCR and 16S rDNA or rrs by nested PCR) and detected lipL32 in 47 (29%) and rrs gene in 63 (38%) patients. The use of more than one target gene for PCR increased the detection rates. Hence, a highly sensitive multiplex PCR targeting more than one diagnostic marker is recommended for the early detection of Leptospira in suspected patients. When the frequencies for positivity detected either by MAT or PCR combined, leptospirosis was diagnosed in a total of 92 (56%) patients, a higher frequency compared to when samples were only tested by a single method (MAT or PCR). The results from this study suggest the inclusion of both serology and molecular methods for every first sample irrespective of the days post-onset of symptoms (DPO) collected from patients for early diagnosis of leptospirosis.
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Affiliation(s)
- Noraini Philip
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Norliza Bahtiar Affendy
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Siti Norbaya Masri
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Muhamad Yazli Yuhana
- Infectious Diseases Unit, Internal Medicine Department, Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia
| | - Leslie Thian Lung Than
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Zamberi Sekawi
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Vasantha Kumari Neela
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
- * E-mail:
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12
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Lethal Outcome of Leptospirosis in Southern Russia: Characterization of Leptospira Interrogans Isolated from a Deсeased Teenager. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17124238. [PMID: 32545855 PMCID: PMC7344687 DOI: 10.3390/ijerph17124238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/09/2020] [Accepted: 06/12/2020] [Indexed: 02/06/2023]
Abstract
This article describes a lethal case of leptospirosis that occurred in Southern Russia. The Leptospira strain was isolated and characterized using a microscopic agglutination test, MALDI-TOF mass spectrometry, targeted PCR, and high-throughput sequencing. We show that molecular and mass-spectrometry methods can be an alternative to conventional methods of leptospirosis diagnostics and Leptospira study, which require highly qualified staff and can be performed only at specialized laboratories. We also report the first whole genome of L. interrogans isolated in Russia.
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13
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Yih WK, Kulldorff M, Friedman DJ, Leibler JH, Amador JJ, López-Pilarte D, Galloway RL, Ramírez-Rubio O, Riefkohl A, Brooks DR. Investigating Possible Infectious Causes of Chronic Kidney Disease of Unknown Etiology in a Nicaraguan Mining Community. Am J Trop Med Hyg 2020; 101:676-683. [PMID: 31309920 PMCID: PMC6726956 DOI: 10.4269/ajtmh.18-0856] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A chronic kidney disease of unknown etiology (CKDu) has been killing workers in Central America. Occupational heat stress is thought to play an important role. Leptospirosis and hantavirus have been suggested as additional possible risk factors. In a case–control study in a Nicaraguan mining community, a structured survey was administered to adults, and biological measurements and specimens were taken. Serum was analyzed for antibodies to Leptospira and hantavirus. Before statistical analysis, a board-certified nephrologist determined final case and control status based on serum creatinine and other laboratory values. Multivariable analysis was by logistic regression. In sensitivity analyses, cases were restricted to those diagnosed with CKDu in the previous 3 years. Of 320 eligible participants, 112 were classified as presumptive cases, 176 as controls and 32 as indeterminant. The risk of CKDu in those ever having worked in mining or construction was 4.4 times higher than in other participants (odds ratio = 4.44, 95% CI: 1.96–10.0, P = 0.0003). Eighty-three (26%) of the 320 participants were seropositive for at least one tested strain of Leptospira. No evidence of a causal link between leptospirosis or hantavirus and CKDu was found. The sensitivity analyses provide some evidence against the hypotheses that leptospirosis or hantavirus leads to CKDu within a few years. A major limitation was the impossibility of determining the absolute or relative timing of infection and CKDu onset. A prospective cohort design, with repeated collection of specimens over several years, could yield clearer answers about infections as potential etiologic agents in CKDu.
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Affiliation(s)
- W Katherine Yih
- Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts
| | - Martin Kulldorff
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, Massachusetts
| | - David J Friedman
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Jessica H Leibler
- Department of Environmental Health, Boston University School of Public Health, Boston, Massachusetts
| | - Juan José Amador
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts
| | - Damaris López-Pilarte
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts
| | | | - Oriana Ramírez-Rubio
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts
| | - Alejandro Riefkohl
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts
| | - Daniel R Brooks
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts
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Lam JY, Low GKK, Chee HY. Diagnostic accuracy of genetic markers and nucleic acid techniques for the detection of Leptospira in clinical samples: A meta-analysis. PLoS Negl Trop Dis 2020; 14:e0008074. [PMID: 32049960 PMCID: PMC7041858 DOI: 10.1371/journal.pntd.0008074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/25/2020] [Accepted: 01/18/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Leptospirosis is often difficult to diagnose because of its nonspecific symptoms. The drawbacks of direct isolation and serological tests have led to the increased development of nucleic acid-based assays, which are more rapid and accurate. A meta-analysis was performed to evaluate the diagnostic accuracy of genetic markers for the detection of Leptospira in clinical samples. METHODOLOGY AND PRINCIPLE FINDINGS A literature search was performed in Scopus, PubMed, MEDLINE and non-indexed citations (via Ovid) by using suitable keyword combinations. Studies evaluating the performance of nucleic acid assays targeting leptospire genes in human or animal clinical samples against a reference test were included. Of the 1645 articles identified, 42 eligible studies involving 7414 samples were included in the analysis. The diagnostic performance of nucleic acid assays targeting the rrs, lipL32, secY and flaB genes was pooled and analyzed. Among the genetic markers analyzed, the secY gene showed the highest diagnostic accuracy measures, with a pooled sensitivity of 0.56 (95% CI: 0.50-0.63), a specificity of 0.98 (95% CI: 0.97-0.98), a diagnostic odds ratio of 46.16 (95% CI: 6.20-343.49), and an area under the curve of summary receiver operating characteristics curves of 0.94. Nevertheless, a high degree of heterogeneity was observed in this meta-analysis. Therefore, the present findings here should be interpreted with caution. CONCLUSION The diagnostic accuracies of the studies examined for each genetic marker showed a significant heterogeneity. The secY gene exhibited higher diagnostic accuracy measures compared with other genetic markers, such as lipL32, flaB, and rrs, but the difference was not significant. Thus, these genetic markers had no significant difference in diagnostic accuracy for leptospirosis. Further research into these genetic markers is warranted.
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Affiliation(s)
- Jia-Yong Lam
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia
| | - Gary Kim-Kuan Low
- Clinical Research Team, Rapid Response Revival Research Ltd, Riverwood, Sydney, Australia
| | - Hui-Yee Chee
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia
- * E-mail:
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15
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Chiu CH, Chen PC, Wang YC, Lin CL, Lee FY, Wu CC, Chang KH. Risk of Dementia in Patients with Leptospirosis: A Nationwide Cohort Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16173168. [PMID: 31480270 PMCID: PMC6747145 DOI: 10.3390/ijerph16173168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/24/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022]
Abstract
Background: Studies have linked some bacterial infections with an increased likelihood for development of dementia. However, there is a paucity of data on the relationship between dementia and leptospirosis. In view of this, we conducted a retrospective cohort study to determine whether leptospirosis is a risk factor for dementia. Methods: Data were collected from the Taiwan National Health Insurance Research Databases (2000–2010) to investigate the incidence of and risk factors for dementia in patients with leptospirosis. Patients with leptospirosis who did not have a history of dementia were enrolled in the study. For each leptospirosis patient, four controls were randomly selected after frequency matching of age, sex, and index date. Cox proportional hazard regression models were used for the analyses of dementia risk. Results: A greater risk of dementia was observed in the leptospirosis cohort than in the non-leptospirosis cohort both in patients without any comorbidity (adjusted HR (aHR) = 1.23, 95% CI = 1.06–1.43) and with a comorbidity (aHR = 2.06, 95% CI = 1.7–2.5). Compared with the non-leptospirosis cohort without these comorbidities, the leptospirosis cohort with ≥2 comorbidities exhibited a significantly increased risk of dementia (aHR = 6.11, 95% CI = 3.15–11.9), followed by those with any one comorbidity (adjusted HR = 3.62, 95% CI = 1.76–7.46). Conclusions: Patients with leptospirosis were at a 1.89-fold greater risk of subsequent dementia, but potential genetic susceptibility bias in the study group is a major confound.
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Affiliation(s)
- Chun-Hsiang Chiu
- Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center Taipei, Taipei 11490, Taiwan
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan
| | - Po-Chung Chen
- Division of Family Medicine, Department of Community Medicine, Taoyuan Armed Forces General Hospital, Taoyuan 32549, Taiwan
| | - Ying-Chuan Wang
- Department of Family Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan
| | - Cheng-Li Lin
- Management Office for Health Data, China Medical University Hospital, Taichung 40402, Taiwan
- College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Feng-You Lee
- Department of Emergency Medicine, Taichung Tzu Chi Hospital, Taichung 42743, Taiwan
| | - Chia-Chang Wu
- Department of Urology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
| | - Kuang-Hsi Chang
- Department of Medical Research, Tungs' Taichung Metroharbor Hospital, Taichung 43503, Taiwan.
- Institute of Biomedical Sciences, China Medical University, Taichung 40402, Taiwan.
- General Education Center, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli 35664, Taiwan.
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Molecular epidemiology of Leptospira interrogans in Rattus norvegicus in Hanoi, Vietnam. Acta Trop 2019; 194:204-208. [PMID: 30965020 DOI: 10.1016/j.actatropica.2019.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 02/07/2019] [Accepted: 02/09/2019] [Indexed: 11/22/2022]
Abstract
Leptospirosis is a zoonotic disease that is caused by pathogenic spirochaetes of Leptospira spp. and it has become a public health concern in urban localities in the tropics. Rats are important reservoir animals for the transmission of leptospirosis in urban areas. Leptospirosis is considered endemic in Vietnam. However, information on the causative Leptospira genotypes and serotypes in the country is limited. We investigated the carrier status of Leptospira spp. in rats captured in Hanoi by culturing and DNA detection. Isolates were characterized using a serological method and multiple-locus variable-number tandem repeat analysis (MLVA). We captured 144 rats (1 Rattus argentiventer, 135 R. norvegicus, and 8 R. rattus) and obtained 17 L. interrogans, determined by rrs sequencing, from R. norvegicus (12.6%). Sixteen of the isolates were serogroup Bataviae. Five of the 16 isolates exhibited an MLVA type identical to that of the serovar Bataviae reference strain Van Tienen, while there were nine repeats for the other 11 isolates at VNTR31 compared with the reference strain. The remaining isolate grew poorly, and we were unable to determine its serogroup. However, it had an MLVA type matching those of serogroup Pomona strains isolated from R. norvegicus in Japan. Three different flaB sequences were detected in 23 out of 81 R. norvegicus kidney tissue samples (28.4%) using nested PCR followed by DNA sequencing. Two of the sequences were identical with those of serogroups Bataviae and Pomona, and no strain with another sequence was detected in the present study. The present study reveals a high prevalence rate of L. interrogans among R. norvegicus in Hanoi, Vietnam, indicating a potential risk of rat-borne leptospirosis in the area. The present study also demonstrates that a fastidious L. interrogans strain circulates among rats and that molecular detection is crucial in facilitating the accurate determination of reservoir animals.
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Evaluation of a Rapid Kit for Detection of IgM against Leptospira in Human. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2019; 2019:5763595. [PMID: 30881530 PMCID: PMC6383415 DOI: 10.1155/2019/5763595] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 01/09/2019] [Accepted: 01/23/2019] [Indexed: 11/28/2022]
Abstract
Introduction Leptospirosis is an acute febrile illness, known for its protean clinical manifestations and the challenge in differentiating from other infectious diseases. Standardized confirmatory test is antibody dependent and not accessible by the suburban community. This study measures efficiency of an immune-chromatographic assay, Leptocheck WB, in detecting acute leptospirosis. Methods A total of 142 sera were used for kit evaluation. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated by comparing rapid kit results with gold standard laboratory, microscopic agglutination test (MAT). Results We found this rapid kit to have a sensitivity and specificity of 66.6% and 78.9%, respectively, whereas the PPV and NPV of the kit appeared to be 73.3% and 73.2%, respectively. Discussion Test efficiency of this rapid kit is reasonable. It is specific in detecting leptospiral antibody and assures clinician of accurate diagnosis by having higher PPV and NPV. It is prompt and efficient in comparison with conventional methods in assisting differential diagnosis. High sensitivity and specificity leptospirosis rapid test is indeed a crucial measure to assist the diagnosis of acute undifferentiated febrile illnesses.
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18
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de Vries SG, Visser BJ, Stoney RJ, Wagenaar JFP, Bottieau E, Chen LH, Wilder-Smith A, Wilson M, Rapp C, Leder K, Caumes E, Schwartz E, Hynes NA, Goorhuis A, Esposito DH, Hamer DH, Grobusch MP. Leptospirosis among Returned Travelers: A GeoSentinel Site Survey and Multicenter Analysis-1997-2016. Am J Trop Med Hyg 2018; 99:127-135. [PMID: 29761761 PMCID: PMC6085784 DOI: 10.4269/ajtmh.18-0020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 04/04/2018] [Indexed: 12/24/2022] Open
Abstract
Leptospirosis is a potentially fatal emerging zoonosis with worldwide distribution and a broad range of clinical presentations and exposure risks. It typically affects vulnerable populations in (sub)tropical countries but is increasingly reported in travelers as well. Diagnostic methods are cumbersome and require further improvement. Here, we describe leptospirosis among travelers presenting to the GeoSentinel Global Surveillance Network. We performed a descriptive analysis of leptospirosis cases reported in GeoSentinel from January 1997 through December 2016. We included 180 travelers with leptospirosis (mostly male; 74%; mostly tourists; 81%). The most frequent region of infection was Southeast Asia (52%); the most common source countries were Thailand (N = 52), Costa Rica (N = 13), Indonesia, and Laos (N = 11 each). Fifty-nine percent were hospitalized; one fatality was reported. We also distributed a supplemental survey to GeoSentinel sites to assess clinical and diagnostic practices. Of 56 GeoSentinel sites, three-quarters responded to the survey. Leptospirosis was reported to have been most frequently considered in febrile travelers with hepatic and renal abnormalities and a history of freshwater exposure. Serology was the most commonly used diagnostic method, although convalescent samples were reported to have been collected infrequently. Within GeoSentinel, leptospirosis was diagnosed mostly among international tourists and caused serious illness. Clinical suspicion and diagnostic workup among surveyed GeoSentinel clinicians were mainly triggered by a classical presentation and exposure history, possibly resulting in underdiagnosis. Suboptimal usage of available diagnostic methods may have resulted in additional missed, or misdiagnosed, cases.
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Affiliation(s)
- Sophia G. de Vries
- Center for Tropical Medicine and Travel Medicine, Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, The Netherlands
| | - Benjamin J. Visser
- Center for Tropical Medicine and Travel Medicine, Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, The Netherlands
| | - Rhett J. Stoney
- Travelers’ Health Branch, Division of Global Migration and Quarantine, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia
| | - Jiri F. P. Wagenaar
- Department of Medical Microbiology, Leptospirosis Reference Center, Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, The Netherlands
| | - Emmanuel Bottieau
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Lin H. Chen
- Travel Medicine Center, Mount Auburn Hospital, Cambridge, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Annelies Wilder-Smith
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore
- Institute of Public Health, University of Heidelberg, Heidelberg, Germany
| | - Mary Wilson
- School of Medicine Global Health Sciences, University of California, San Francisco, San Francisco, California
| | - Christophe Rapp
- Service des Maladies Infectieuses et Tropicales, Hôpital d'Instruction des Armées Bégin, Paris, France
- CMETE Travel clinic, Paris, France
| | - Karin Leder
- School of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia
- Victorian Infectious Disease Service, Royal Melbourne Hospital at the Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Eric Caumes
- Service des Maladies Infectieuses et Tropicales, Hôpital Pitié-Salpêtrière, Sorbonne Université, Paris, France
| | - Eli Schwartz
- Department of Internal Medicine “C”, The Center of Geographical Medicine, Sheba Medical Center, Tel HaShomer, Ramat Gan, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Noreen A. Hynes
- Division of Infectious Diseases, Geographic Medicine Center, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Abraham Goorhuis
- Center for Tropical Medicine and Travel Medicine, Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, The Netherlands
| | - Douglas H. Esposito
- Travelers’ Health Branch, Division of Global Migration and Quarantine, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia
| | - Davidson H. Hamer
- Department of Global Health, Boston University School of Public Health, Boston, Maryland
| | - Martin P. Grobusch
- Center for Tropical Medicine and Travel Medicine, Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, The Netherlands
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
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Moreira J, Bressan CS, Brasil P, Siqueira AM. Epidemiology of acute febrile illness in Latin America. Clin Microbiol Infect 2018; 24:827-835. [PMID: 29777926 PMCID: PMC7172187 DOI: 10.1016/j.cmi.2018.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/01/2018] [Accepted: 05/03/2018] [Indexed: 12/11/2022]
Abstract
Background The causes of acute febrile illness (AFI) in Latin America are diverse and their complexity increases as the proportion of fever due to malaria decreases, as malaria control measures and new pathogens emerge in the region. In this context, it is important to shed light on the gaps in the epidemiological characteristics and the geographic range for many AFI aetiologies. Objectives To review studies on community-acquired fever aetiology other than malaria in Latin America, and to highlight knowledge gaps and challenges needing further investigation. Sources PubMed from 2012 to April 2018. Content We found 17 eligible studies describing 13 539 patients. The median number of pathogens tested per individual was 3.5 (range 2–17). A causative pathogen could be determined for 6661 (49.2%) individuals. The most frequently reported pathogen during the study periods was dengue virus (DENV) (14 studies), followed by chikungunya virus (nine studies) and Zika virus (seven studies). Among the studies reporting concurrent infections, 296 individuals (2.2%) were found to have co-infections. In-hospital mortality was reported in eight (47%) studies, ranging between 0% and 18%. Implications DENV fever is the febrile illness most frequently reported, reflecting its importance, while chikungunya and zika viruses present increasing trends since their emergence in the region. Studies with systematic and harmonized approaches for detection of multiple pathogens are needed and would probably reveal a higher burden of neglected pathogens such as Rickettsia spp. and arenaviruses. The lack of point-of-care tests and harmonized approach limits the care provided by health professionals and the efficacy of surveillance for AFI in the region.
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Affiliation(s)
- J Moreira
- Instituto Nacional de Infectologia Evandro Chagas, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil; Programa de Pós-Graduação em Pesquisa Clínica, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil
| | - C S Bressan
- Instituto Nacional de Infectologia Evandro Chagas, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil; Programa de Pós-Graduação em Pesquisa Clínica, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil
| | - P Brasil
- Instituto Nacional de Infectologia Evandro Chagas, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil; Programa de Pós-Graduação em Pesquisa Clínica, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil
| | - A M Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil; Programa de Pós-Graduação em Pesquisa Clínica, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil.
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Meny P, Menéndez C, Quintero J, Hernández E, Ríos C, Balassiano IT, Trindade CNDR, Vital-Brazil JM, Ramos TMV, Ashfield N, Feble C, Avila E, Schelotto F, Varela G. Characterization of Leptospira isolates from humans and the environment in Uruguay. Rev Inst Med Trop Sao Paulo 2017; 59:e79. [PMID: 29267587 PMCID: PMC5738764 DOI: 10.1590/s1678-9946201759079] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 09/12/2017] [Indexed: 01/30/2023] Open
Abstract
Laboratory diagnosis of human leptospirosis usually relies on indirect methods exploring specific immune response. Isolation and identification of the involved strains are cumbersome, but can provide biological resources for pathogenic studies and relevant information for guiding prevention and control measures. The aim of the research we are hereby reporting was the characterization of Leptospira isolates obtained from humans and the environment in Uruguay. Blood cultures were performed from early samples of 302 Uruguayan patients, mainly rural workers, and from 36 water samples taken from their living or working environments. Eight human isolates and seven environmental isolates were obtained and analyzed by end point Polymerase Chain Reaction (PCR), Multilocus Variable Number of Tandem Repeat Analysis (MLVA) and other molecular methods. Human isolates corresponded to several serogroups and serovars of Leptospira interrogans and Leptospira kirschneri species, probably reflecting the infection with similar involved Leptospira species and serovars of an extended animal reservoir in rural settings of the country, mostly dedicated to meat and dairy production. Culture-positive patients were older than usually affected workers, and presented signs and symptoms of severe illness. A high organic and circulating bacterial burden may explain an easier positive result from these workers’ samples. Environmental isolates were mainly identified as Leptospira biflexa strains, with a single L. meyeri isolate of uncertain significance.
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Affiliation(s)
| | | | | | | | | | - Ilana Teruszkin Balassiano
- Instituto Osvaldo Cruz, Centro de Referência Nacional para Leptospirose, WHO Collaborating Center for Leptospirosis, Laboratório de Zoonoses Bacterianas, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Camilla Nunes Dos Reis Trindade
- Instituto Osvaldo Cruz, Centro de Referência Nacional para Leptospirose, WHO Collaborating Center for Leptospirosis, Laboratório de Zoonoses Bacterianas, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Juliana Magalhães Vital-Brazil
- Instituto Osvaldo Cruz, Centro de Referência Nacional para Leptospirose, WHO Collaborating Center for Leptospirosis, Laboratório de Zoonoses Bacterianas, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tatiane Mendes Varela Ramos
- Instituto Osvaldo Cruz, Centro de Referência Nacional para Leptospirose, WHO Collaborating Center for Leptospirosis, Laboratório de Zoonoses Bacterianas, Rio de Janeiro, Rio de Janeiro, Brazil
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Ribeiro P, Bhatt N, Ali S, Monteiro V, da Silva E, Balassiano IT, Aquino C, de Deus N, Guiliche O, Muianga AF, Alho PJ, Lara Evaristo V, Manhiça I, Medeiros M, Gudo ES. Seroepidemiology of leptospirosis among febrile patients in a rapidly growing suburban slum and a flood-vulnerable rural district in Mozambique, 2012-2014: Implications for the management of fever. Int J Infect Dis 2017; 64:50-57. [PMID: 28893674 DOI: 10.1016/j.ijid.2017.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/29/2017] [Accepted: 08/31/2017] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE Leptospirosis is one of the most widespread zoonoses in the world and is caused by spirochetes of the genus Leptospira. In Mozambique, the disease is largely ignored and its epidemiology is unknown. The objective of this study was to investigate the occurrence of leptospirosis in febrile patients. METHODS This cross-sectional study was performed between July 2012 and September 2015 among febrile patients. A total of 373 paired serum samples were drawn from febrile patients; 208 were from Caia District Hospital (rural setting) in Sofala Province and 165 were from Polana Caniço General Hospital (suburban setting) in Maputo City. Samples were initially screened using an in-house ELISA for IgM and IgG antibodies. Double positive samples were confirmed using a microagglutination test (MAT). RESULTS Of the 373 febrile patients, five (1.3%) had acute leptospirosis (MAT ≥400) and 38 (10.2%) had a presumptive infection (IgM-positive/MAT <400). While most of the patients with a presumptive infection lived in the rural setting (84.2%, 32/38), the majority of patients with acute infections (60%, 3/5) and with negative results (60.3%, 199/330) lived in the suburban setting (p=0.000). Contact with rodents was significantly higher in patient with acute leptospirosis (100%, 5/5) than in those with a presumptive infection (39.5%, 15/38) or negative results (41.8%, 138/330) (p=0.031). Four out of the five patients (80%) with acute leptospirosis were treated with antimalarial drugs although malaria results were negative. The prevailing serogroup, according to MAT results, was Australis (40%; 4/10), followed by Icterohaemorrhagiae (30%, 3/10). CONCLUSIONS This study found that leptospirosis is prevalent among Mozambicans, and most cases are misdiagnosed as malaria.
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Affiliation(s)
| | - Nilesh Bhatt
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | - Sádia Ali
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | - Vanessa Monteiro
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | - Edmilson da Silva
- Laboratório Tecnologia Diagnóstico Bio-Manguinhos, Fiocruz, Rio de Janeiro, Brazil
| | - Ilana Teruszkin Balassiano
- Laboratório de Zoonoses Bacterianas, Serviço de Referência Nacional para Leptospirose, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
| | - Carolina Aquino
- Laboratório Tecnologia Recombinante, Bio-Manguinhos, Fiocruz, Rio de Janeiro, Brazil
| | - Nilsa de Deus
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | - Onelia Guiliche
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | | | | | | | - Ivan Manhiça
- Direcção Nacional de Saúde Pública, Ministry of Health, Maputo, Mozambique
| | - Marco Medeiros
- Laboratório Tecnologia Recombinante, Bio-Manguinhos, Fiocruz, Rio de Janeiro, Brazil
| | - Eduardo Samo Gudo
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique.
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Flores BJ, Pérez-Sánchez T, Fuertes H, Sheleby-Elías J, Múzquiz JL, Jirón W, Duttmann C, Halaihel N. A cross-sectional epidemiological study of domestic animals related to human leptospirosis cases in Nicaragua. Acta Trop 2017; 170:79-84. [PMID: 28254582 DOI: 10.1016/j.actatropica.2017.02.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 02/23/2017] [Accepted: 02/26/2017] [Indexed: 10/20/2022]
Abstract
Leptospirosis is one of the most extended zoonosis worldwide and humans become infected most commonly through contact with the urine of carrier animals, either directly or via contaminated water or soil. The aim in this study was to analyse the epidemiological behaviour of Leptospira spp., from domestic animals around the sites of human leptospirosis cases in Nicaragua, from 2007 through 2013. We report the results of a cross-sectional epidemiological study with a non-probability sampling of blood (n=3050) and urine (n=299) from Domestic Animals (DA) around the sites of human leptospirosis cases in Nicaragua. We analysed data obtained through Microscopic Agglutination Test (MAT), in-vitro culture, real time PCR and sequencing of lfb1 locus. Frequencies of 30.31% (95% CI: 28.66-31.95) and 15.38% (95% CI: 11.12-19.64) were obtained from serological test and from in-vitro culture, respectively. Although similar frequencies from serology test (P≥0.05) were found in DA species, in-vitro culture frequencies were significantly higher from bovine, equine and sheep (P<0.05) in comparison with swine and canine species. Ten serogroups of pathogenic Leptospira spp. were encountered, with the highest presence of Icterohaemorrhagiae serogroup 34.65% (95% CI: 29.35-39.94). We identified 7 samples homologous to L. interrogans species Pyrogenes serovar and 3 samples as L. noguchii Louisiana or Panama serovars by analysis of lfb1 sequences. We were able to establish a temporal and spatial correlation from DA and cumulative incidence of human cases. Therefore an effective epidemiological surveillance should be implemented with a specific control program toward DA in order to reduce human leptospirosis incidence.
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Fischer RSB, Flores Somarriba B. Challenges to Diagnosing Leptospirosis in Endemic Regions Require Urgent Attention. CURRENT TROPICAL MEDICINE REPORTS 2017. [DOI: 10.1007/s40475-017-0110-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Svarch AE, Arce-Salinas CA, Amaya JL. Leptospirosis in Mesoamerica. CURRENT TROPICAL MEDICINE REPORTS 2017. [DOI: 10.1007/s40475-017-0105-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Muller SK, Assenga JA, Matemba LE, Misinzo G, Kazwala RR. Human leptospirosis in Tanzania: sequencing and phylogenetic analysis confirm that pathogenic Leptospira species circulate among agro-pastoralists living in Katavi-Rukwa ecosystem. BMC Infect Dis 2016; 16:273. [PMID: 27287703 PMCID: PMC4902944 DOI: 10.1186/s12879-016-1588-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 05/21/2016] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Leptospirosis is a neglected zoonotic disease of worldwide public health importance. The disease affects humans, domestic animals and wildlife. However, leptospirosis is challenging in its diagnosis in humans. Culture technique, which is time consuming, is not recommended for clinical diagnosis. For these reasons, serological and molecular techniques remain the test of choice. The major objective of this study was to explore the genetic characteristic of Leptospira species which are prevalent among agro-pastoralists living in Katavi-Rukwa Ecosystem, Tanzania. METHODS A cross-sectional epidemiological study was carried out in the Katavi-Region South-west, Tanzania between August, 2013 and November, 2014. A total of 267 participants were randomly recruited for the study. Microscopic agglutination test (MAT) was used to detect antibody against six Leptospira antigens including local serogroups Icterohaemorrhagiae, Ballum, Grippotyphosa, Sejroe and reference serogroups Hebdomadis, and Australis. Samples with MAT titers ≥ 1:160 were scored as positive, samples with MAT titers ranging from 1:20 to 1:80 were scored as exposed to Leptospira, and absence of agglutination titers was scored as negative. All MAT positive samples, including the low titre samples were subjected to PCR using the respective 16S rRNA primers for the pathogenic and non-pathogenic species. RESULTS Out of 267 samples tested, 80 (29.9 %) were positive with MAT. The major circulating leptospiral serogroups were Sejroe (15.7 %,), Icterohaemorrhagiae (8.9 %), Grippotyphosa (4.8 %), Hebdomadis (3.37 %), Australis (1.49 %) and Ballum (1.19 %). By using PCR, 33 (15.7 %) out of 210 samples were pathogenic Leptospira while no saprophytic Leptospira spp. was detected. Partial 16S rRNA gene sequences of Leptospira species which were obtained from this study were submitted to GenBank and acquired accession numbers KP313246 and KP313247. Phylogenetic analysis of the nucleotide sequences revealed that species obtained from Katavi-Rukwa ecosystem clustered in the same group with several published pathogenic Leptospira specifically Leptospira interrogans and Leptospira kirschneri. To the best of the authors' knowledge(,) this is the first study from Tanzania to confirm pathogenic Leptospira in human subjects using genomic typing technique. CONCLUSION These findings provide ultimate evidence of pathogenic Leptospira species circulating among agro-pastoralists living in Katavi-Rukwa Ecosystem suggesting that active disease surveillance should be undertaken in order to achieve greater protection of the agro-pastoral communities in Tanzania.
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Affiliation(s)
- Shabani K Muller
- Sokoine University of Agriculture, Morogoro, Tanzania.
- National Institute for Medical Research (NIMR), MOMS clinical Trial, Morogoro, Tanzania.
| | | | - Lucas E Matemba
- National Institute for Medical Research (NIMR), MOMS clinical Trial, Morogoro, Tanzania
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Use of Peptide-Based Enzyme-Linked Immunosorbent Assay followed by Immunofluorescence Assay To Document Ehrlichia chaffeensis as a Cause of Febrile Illness in Nicaragua. J Clin Microbiol 2016; 54:1581-1585. [PMID: 27053675 DOI: 10.1128/jcm.03331-15] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/31/2016] [Indexed: 11/20/2022] Open
Abstract
Ehrlichia chaffeensis, the etiologic agent of human monocytic ehrlichiosis (HME), has been extensively studied as a cause of acute febrile illness and an emerging tick-borne zoonosis in the United States. Limited data suggest its presence in other regions, including Central and South America but not Nicaragua to date. Diagnosis of E. chaffeensis infection by indirect immunofluorescence assay (IFA) is the reference standard due to its presumed high sensitivity and specificity, but IFA is impractical, variably reproducible, and cumbersome for large epidemiologic studies and for clinical diagnosis in resource-poor regions. We evaluated a high-throughput, objective peptide-based enzyme-linked immunosorbent assay (ELISA) for use alone or in combination with IFA. We found that it performed best as a screening test (sensitivity, 100%; specificity, 84%) to reduce the proportion of serum samples that were required by the more cumbersome and subjective IFA testing to <20%. Using a two-step diagnostic approach (IFA is performed if the ELISA is positive), we identified E. chaffeensis or a serologically and antigenically similar organism as a heretofore unrecognized cause of acute febrile illness in humans in Nicaragua and demonstrated the utility of the peptide ELISA as a screening tool for large-scale clinical studies.
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Costa F, Hagan JE, Calcagno J, Kane M, Torgerson P, Martinez-Silveira MS, Stein C, Abela-Ridder B, Ko AI. Global Morbidity and Mortality of Leptospirosis: A Systematic Review. PLoS Negl Trop Dis 2015; 9:e0003898. [PMID: 26379143 PMCID: PMC4574773 DOI: 10.1371/journal.pntd.0003898] [Citation(s) in RCA: 964] [Impact Index Per Article: 107.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 06/10/2015] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Leptospirosis, a spirochaetal zoonosis, occurs in diverse epidemiological settings and affects vulnerable populations, such as rural subsistence farmers and urban slum dwellers. Although leptospirosis is a life-threatening disease and recognized as an important cause of pulmonary haemorrhage syndrome, the lack of global estimates for morbidity and mortality has contributed to its neglected disease status. METHODOLOGY/PRINCIPAL FINDINGS We conducted a systematic review of published morbidity and mortality studies and databases to extract information on disease incidence and case fatality ratios. Linear regression and Monte Carlo modelling were used to obtain age and gender-adjusted estimates of disease morbidity for countries and Global Burden of Disease (GBD) and WHO regions. We estimated mortality using models that incorporated age and gender-adjusted disease morbidity and case fatality ratios. The review identified 80 studies on disease incidence from 34 countries that met quality criteria. In certain regions, such as Africa, few quality assured studies were identified. The regression model, which incorporated country-specific variables of population structure, life expectancy at birth, distance from the equator, tropical island, and urbanization, accounted for a significant proportion (R(2) = 0.60) of the variation in observed disease incidence. We estimate that there were annually 1.03 million cases (95% CI 434,000-1,750,000) and 58,900 deaths (95% CI 23,800-95,900) due to leptospirosis worldwide. A large proportion of cases (48%, 95% CI 40-61%) and deaths (42%, 95% CI 34-53%) were estimated to occur in adult males with age of 20-49 years. Highest estimates of disease morbidity and mortality were observed in GBD regions of South and Southeast Asia, Oceania, Caribbean, Andean, Central, and Tropical Latin America, and East Sub-Saharan Africa. CONCLUSIONS/SIGNIFICANCE Leptospirosis is among the leading zoonotic causes of morbidity worldwide and accounts for numbers of deaths, which approach or exceed those for other causes of haemorrhagic fever. Highest morbidity and mortality were estimated to occur in resource-poor countries, which include regions where the burden of leptospirosis has been underappreciated.
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Affiliation(s)
- Federico Costa
- Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Bahia, Brazil
- Institute of Collective Health, Federal University of Bahia, UFBA, Salvador, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - José E. Hagan
- Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Bahia, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Juan Calcagno
- Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Bahia, Brazil
| | - Michael Kane
- Center for Analytical Sciences, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Paul Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | | | - Claudia Stein
- Division of Information, Evidence, Research and Innovation, World Health Organization, Regional Office for Europe, UN City, Copenhagen Ø, Denmark
| | - Bernadette Abela-Ridder
- Department for the Control of Neglected Tropical Diseases, World Health Organization, Genève, Switzerland
| | - Albert I. Ko
- Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Bahia, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
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Taylor AJ, Paris DH, Newton PN. A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi). PLoS Negl Trop Dis 2015; 9:e0003971. [PMID: 26274584 PMCID: PMC4537241 DOI: 10.1371/journal.pntd.0003971] [Citation(s) in RCA: 190] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 07/10/2015] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Scrub typhus, a bacterial infection caused by Orientia tsutsugamushi, is increasingly recognized as an important cause of fever in Asia, with an estimated one million infections occurring each year. Limited access to health care and the disease's non-specific symptoms mean that many patients are undiagnosed and untreated, but the mortality from untreated scrub typhus is unknown. This review systematically summarizes the literature on the untreated mortality from scrub typhus and disease outcomes. METHODOLOGY/PRINCIPAL FINDINGS A literature search was performed to identify patient series containing untreated patients. Patients were included if they were symptomatic and had a clinical or laboratory diagnosis of scrub typhus and excluded if they were treated with antibiotics. The primary outcome was mortality from untreated scrub typhus and secondary outcomes were total days of fever, clinical symptoms, and laboratory results. A total of 76 studies containing 89 patient series and 19,644 patients were included in the final analysis. The median mortality of all patient series was 6.0% with a wide range (min-max) of 0-70%. Many studies used clinical diagnosis alone and had incomplete data on secondary outcomes. Mortality varied by location and increased with age and in patients with myocarditis, delirium, pneumonitis, or signs of hemorrhage, but not according to sex or the presence of an eschar or meningitis. Duration of fever was shown to be long (median 14.4 days Range (9-19)). CONCLUSIONS Results show that the untreated mortality from scrub typhus appears lower than previously reported estimates. More data are required to clarify mortality according to location and host factors, clinical syndromes including myocarditis and central nervous system disease, and in vulnerable mother-child populations. Increased surveillance and improved access to diagnostic tests are required to accurately estimate the untreated mortality of scrub typhus. This information would facilitate reliable quantification of DALYs and guide empirical treatment strategies.
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Affiliation(s)
- Andrew J. Taylor
- Lao Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Daniel H. Paris
- Lao Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
- Mahidol–Oxford Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paul N. Newton
- Lao Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
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Taylor AJ, Paris DH, Newton PN. A Systematic Review of the Mortality from Untreated Leptospirosis. PLoS Negl Trop Dis 2015; 9:e0003866. [PMID: 26110270 PMCID: PMC4482028 DOI: 10.1371/journal.pntd.0003866] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/01/2015] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Leptospirosis occurs worldwide, but the global incidence of human disease and its mortality are not well understood. Many patients are undiagnosed and untreated due to its non-specific symptoms and a lack of access to diagnostics. This study systematically reviews the literature to clarify the mortality from untreated leptospirosis. Results will help quantify the global burden of disease and guide health policies. METHODOLOGY/PRINCIPAL FINDINGS A comprehensive literature search was performed to identify untreated patient series. Included patients were symptomatic, but asymptomatic patients and those who had received antibiotics, dialysis or who were treated on Intensive Care Units were excluded. Included patients had a confirmed laboratory diagnosis by culture, PCR, or serological tests. Data was extracted and individual patient series were assessed for bias. Thirty-five studies, comprising 41 patient series and 3,390 patients, were included in the study. A high degree of bias within studies was shown due to limitations in study design, diagnostic tests and missing data. Median series mortality was 2.2% (Range 0.0-39.7%), but mortality was high in jaundiced patients (19.1%) (Range 0.0-39.7%), those with renal failure 12.1% (Range 0-25.0%) and in patients aged over 60 (60%) (Range 33.3-60%), but low in anicteric patients (0%) (Range 0-1.7%). CONCLUSIONS This systematic review contributes to our understanding of the mortality of untreated leptospirosis and provides data for the estimation of DALYs attributable to this disease. We show that mortality is significantly higher in older patients with icteric disease or renal failure but is lower in younger, anicteric patients. Increased surveillance and accurate point-of-care diagnostics are required to better understand the incidence and improve diagnosis of disease. Empirical treatment strategies should prioritize early treatment to improve outcomes from leptospirosis.
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Affiliation(s)
- Andrew J. Taylor
- Lao Oxford Mahosot Hospital Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Daniel H. Paris
- Lao Oxford Mahosot Hospital Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
- Mahidol–Oxford Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paul N. Newton
- Lao Oxford Mahosot Hospital Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
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Backstedt BT, Buyuktanir O, Lindow J, Wunder EA, Reis MG, Usmani-Brown S, Ledizet M, Ko A, Pal U. Efficient Detection of Pathogenic Leptospires Using 16S Ribosomal RNA. PLoS One 2015; 10:e0128913. [PMID: 26091292 PMCID: PMC4474562 DOI: 10.1371/journal.pone.0128913] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/01/2015] [Indexed: 01/30/2023] Open
Abstract
Pathogenic Leptospira species cause a prevalent yet neglected zoonotic disease with mild to life-threatening complications in a variety of susceptible animals and humans. Diagnosis of leptospirosis, which primarily relies on antiquated serotyping methods, is particularly challenging due to presentation of non-specific symptoms shared by other febrile illnesses, often leading to misdiagnosis. Initiation of antimicrobial therapy during early infection to prevent more serious complications of disseminated infection is often not performed because of a lack of efficient diagnostic tests. Here we report that specific regions of leptospiral 16S ribosomal RNA molecules constitute a novel and efficient diagnostic target for PCR-based detection of pathogenic Leptospira serovars. Our diagnostic test using spiked human blood was at least 100-fold more sensitive than corresponding leptospiral DNA-based quantitative PCR assays, targeting the same 16S nucleotide sequence in the RNA and DNA molecules. The sensitivity and specificity of our RNA assay against laboratory-confirmed human leptospirosis clinical samples were 64% and 100%, respectively, which was superior then an established parallel DNA detection assay. Remarkably, we discovered that 16S transcripts remain appreciably stable ex vivo, including untreated and stored human blood samples, further highlighting their use for clinical detection of L. interrogans. Together, these studies underscore a novel utility of RNA targets, specifically 16S rRNA, for development of PCR-based modalities for diagnosis of human leptospirosis, and also may serve as paradigm for detection of additional bacterial pathogens for which early diagnosis is warranted.
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Affiliation(s)
- Brian T. Backstedt
- Department of Veterinary Medicine and Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Ozlem Buyuktanir
- Department of Veterinary Medicine and Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | - Janet Lindow
- Department of Epidemiology of Microbial Diseases, Yale University School of Public Health, New Haven, Connecticut, United States of America
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Elsio A. Wunder
- Department of Epidemiology of Microbial Diseases, Yale University School of Public Health, New Haven, Connecticut, United States of America
| | - Mitermayer G. Reis
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | | | - Michel Ledizet
- L2 Diagnostics, New Haven, Connecticut, United States of America
| | - Albert Ko
- Department of Epidemiology of Microbial Diseases, Yale University School of Public Health, New Haven, Connecticut, United States of America
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Utpal Pal
- Department of Veterinary Medicine and Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
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31
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Chikeka I, Dumler JS. Neglected bacterial zoonoses. Clin Microbiol Infect 2015; 21:404-15. [PMID: 25964152 DOI: 10.1016/j.cmi.2015.04.022] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 04/24/2015] [Accepted: 04/25/2015] [Indexed: 01/07/2023]
Abstract
Bacterial zoonoses comprise a group of diseases in humans or animals acquired by direct contact with or by oral consumption of contaminated animal materials, or via arthropod vectors. Among neglected infections, bacterial zoonoses are among the most neglected given emerging data on incidence and prevalence as causes of acute febrile illness, even in areas where recognized neglected tropical diseases occur frequently. Although many other bacterial infections could also be considered in this neglected category, five distinct infections stand out because they are globally distributed, are acute febrile diseases, have high rates of morbidity and case fatality, and are reported as commonly as malaria, typhoid or dengue virus infections in carefully designed studies in which broad-spectrum diagnoses are actively sought. This review will focus attention on leptospirosis, relapsing fever borreliosis and rickettsioses, including scrub typhus, murine typhus and spotted fever group rickettsiosis. Of greatest interest is the lack of distinguishing clinical features among these infections when in humans, which confounds diagnosis where laboratory confirmation is lacking, and in regions where clinical diagnosis is often attributed to one of several perceived more common threats. As diseases such as malaria come under improved control, the real impact of these common and under-recognized infections will become evident, as will the requirement for the strategies and allocation of resources for their control.
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Affiliation(s)
- I Chikeka
- Departments of Pathology and Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - J S Dumler
- Departments of Pathology and Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA.
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32
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Chipwaza B, Mhamphi GG, Ngatunga SD, Selemani M, Amuri M, Mugasa JP, Gwakisa PS. Prevalence of bacterial febrile illnesses in children in Kilosa district, Tanzania. PLoS Negl Trop Dis 2015; 9:e0003750. [PMID: 25955522 PMCID: PMC4425467 DOI: 10.1371/journal.pntd.0003750] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 04/10/2015] [Indexed: 12/04/2022] Open
Abstract
INTRODUCTION Bacterial etiologies of non-malaria febrile illnesses have significantly become important due to high mortality and morbidity, particularly in children. Despite their importance, there are few reports on the epidemiology of these diseases in Tanzania, and the true burden of such illnesses remains unknown. This study aimed to identify the prevalence of leptospirosis, brucellosis, typhoid fever and urinary tract infections and their rate of co-infections with malaria. METHODS A cross-sectional study was conducted at Kilosa district hospital in Tanzania for 6 months. Febrile children aged from 2-13 years were recruited from the outpatient department. Patients were screened by serological tests such as IgM and IgG ELISA, and microscopic agglutination test. RESULTS A total of 370 patients were enrolled; of these 85 (23.0%) had malaria parasites, 43 (11.6%) had presumptive acute leptospirosis and 26/200 (13%) had confirmed leptospirosis. Presumptive acute brucellosis due to B. abortus was identified among 26 (7.0%) of patients while B. melitensis was detected in 57 (15.4%) of the enrolled patients. Presumptive typhoid fever due to S. Typhi was identified in thirty eight (10.3%) of the participants and 69 (18.6%) had urinary tract infections. Patients presented with similar symptoms; therefore, the identification of these diseases could not be done based on clinical ground alone. Co-infections between malaria and bacterial febrile illnesses were observed in 146 patients (39.5%). Although antibacterials and/or anti-malarials were prescribed in most patients, some patients did not receive the appropriate treatment. CONCLUSION The study has underscored the importance of febrile bacterial diseases including zoonoses such as leptospirosis and brucellosis in febrile children, and thus such illnesses should be considered by clinicians in the differential diagnoses of febrile diseases. However, access to diagnostic tests for discrimination of febrile illnesses is needed. This would allow febrile patients to receive the correct diagnoses and facilitation of accurate and prompt treatment.
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Affiliation(s)
- Beatrice Chipwaza
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Ifakara Health Institute, Ifakara, Tanzania
| | - Ginethon G. Mhamphi
- Sokoine University of Agriculture, Pest Management Center, Chuo Kikuu, Morogoro, Tanzania
| | | | | | | | - Joseph P. Mugasa
- National Institute for Medical Research, Amani Medical Research Centre, Tanga, Tanzania
| | - Paul S. Gwakisa
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Genome Science Centre and Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, Morogoro, Tanzania
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