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Cloots K, Singh OP, Singh AK, Rai TK, Tiwari VD, Neyaz A, Pandey S, Scholar VK, Malaviya P, Hasker E, Sundar S. Monitoring of Leishmania transmission in the postelimination phase: The potential of serological surveys. Int J Infect Dis 2024; 147:107153. [PMID: 38936656 DOI: 10.1016/j.ijid.2024.107153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 06/21/2024] [Accepted: 06/21/2024] [Indexed: 06/29/2024] Open
Abstract
OBJECTIVES Monitoring of Leishmania transmission is considered a strategic priority for sustaining elimination of visceral leishmaniasis as a public health problem in the Indian subcontinent. The objective of this study was to evaluate whether serological surveys can distinguish between communities with and without Leishmania transmission, and to assess which serological marker performs best. METHODS Seven villages were selected from Bihar and Uttar Pradesh state, India, and categorized as either currently endemic (CE), previously endemic (PE) or nonendemic (NE). Blood samples were analyzed with the rK39 RDT, direct agglutination test (DAT), and rK39 ELISA. RESULTS Contrary to the rK39 RDT and DAT, the rK39 ELISA showed a significant difference between all three categories of endemicity, with a seroprevalence of 5.21% in CE villages, 1.55% in PE villages, and 0.13% in NE villages. Even when only looking at the seroprevalence among children aged <10 years, the rK39 ELISA was still able to differentiate between villages with and without ongoing transmission. CONCLUSION Our findings suggest the rK39 ELISA to be the most promising marker for monitoring of Leishmania transmission. Further validation is required, and practical, context-adapted recommendations need to be formulated in order to guide policymakers toward meaningful and sustainable surveillance strategies in the post-elimination phase.
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Affiliation(s)
- Kristien Cloots
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
| | - Om Prakash Singh
- Department of Biochemistry, Institute of Sciences, Banaras Hindu University, Varanasi, India
| | - Abhishek Kumar Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Tulika Kumari Rai
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Vishwa Deepak Tiwari
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Aziza Neyaz
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Sundaram Pandey
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Vivek Kumar Scholar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Paritosh Malaviya
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Epco Hasker
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Guha SK, Sardar AA, Misra AK, Saha P, Samanta A, Maji D, Mandal A, Saha P, Halder S, Ali KA, Karmakar S, Sharma D, Maji AK. Active Community-Based Case Finding of Endemic Leishmaniasis in West Bengal, India. J Epidemiol Glob Health 2024:10.1007/s44197-024-00260-2. [PMID: 38884694 DOI: 10.1007/s44197-024-00260-2] [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: 02/16/2024] [Accepted: 06/03/2024] [Indexed: 06/18/2024] Open
Abstract
INTRODUCTION The ongoing visceral leishmaniasis (VL) elimination programme in India is targeting the elimination of the disease VL but not the pathogen. The persistence of hidden parasite pool may initiate a resurgence in suitable conditions. This study dealt with a novel approach to unearth such pathogen pool and their proper management to prevent the resurgence of VL. MATERIALS AND METHODS We deployed a new approach for detection of pathogen pool by following up the VL and post kala-azar dermal leishmaniasis patients treated during the last 10 years along with mass sero-surveillance within a radius of 500 m of recently treated individuals. RESULTS We followed up 72.6% (3026/4168) previously treated VL and post kala-azar dermal leishmaniasis patients and diagnosed 42 (1.4%) new and 38 (1.3%) recurrent post kala-azar dermal leishmaniasis. We detected 93 asymptomatic leishmanial infection, 8 VL and 1 post kala-azar dermal leishmaniasis by mass sero-surveillance. CONCLUSION Our three-step process including mapping and follow-up of previously treated cases, mass surveillance within 500 m of radius of known cases, and 6 monthly follow-on clinical and serological screening of asymptomatic cases, enabled detection of previously undetected cases of post kala-azar dermal leishmaniasis and VL. Recurrent post kala-azar dermal leishmaniasis deserves special attention regarding their treatment guideline. Early diagnosis and effective treatment of all leishmaniasis cases will hasten pathogen elimination and prevent resurgence of VL. This may help the policymakers to develop appropriate strategy for elimination of pathogen to prevent resurgence of VL.
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Affiliation(s)
- Subhasish Kamal Guha
- Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India.
| | - Ashif Ali Sardar
- Department of Microbiology, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
| | - Amartya Kumar Misra
- Department of Tropical Medicine, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
| | - Pabitra Saha
- Department of Microbiology, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
- Department of Zoology, P. R. Thakur Government College, Thakurnagar, North 24 Parganas, West Bengal, India
| | - Anwesha Samanta
- Department of Microbiology, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
| | - Dipankar Maji
- Department of Health and Family Welfare, Government of West Bengal, Swasthya Bhavan, Salt Lake City, Kolkata, West Bengal, India
| | - Amitabha Mandal
- Office of the Chief Medical Officer of Health, Public Health Wing, Malda Medical College Campus, Malda, West Bengal, India
| | - Punita Saha
- R. N. Ray Rural Hospital, Bulbulchandi, Habibpur, Malda, West Bengal, India
| | - Supriya Halder
- Department of Microbiology, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
| | - Kabiul Akhter Ali
- Office of the Chief Medical Officer of Health, Public Health Wing, Malda Medical College Campus, Malda, West Bengal, India
| | - Sibajyoti Karmakar
- Office of the Chief Medical Officer of Health, Public Health Wing, Raiganj, Uttar Dinajpur, West Bengal, India
| | - Dipendra Sharma
- Office of the Chief Medical Officer of Health, Public Health Wing, Siliguri, Darjeeling, West Bengal, India
| | - Ardhendu Kumar Maji
- Department of Microbiology, Calcutta School of Tropical Medicine, 108, C. R. Avenue, Kolkata, West Bengal, India
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Yimer M, Takele Y, Yizengaw E, Nibret E, Sumova P, Volf P, Yismaw G, Alehegn M, Rowan A, Müller I, Cotton JA, Chapman LAC, Kropf P. Demographic characteristics and prevalence of asymptomatic Leishmania donovani infection in migrant workers working in an endemic area in Northwest Ethiopia. FRONTIERS IN EPIDEMIOLOGY 2024; 4:1367387. [PMID: 38655403 PMCID: PMC11035784 DOI: 10.3389/fepid.2024.1367387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/26/2024] [Indexed: 04/26/2024]
Abstract
Introduction Visceral leishmaniasis (VL), a neglected tropical disease that causes substantial morbidity and mortality, is a serious health problem in Ethiopia. Infections are caused by Leishmania (L.) donovani parasites. Most individuals remain asymptomatic, but some develop VL, which is generally fatal if not treated. We identified the area of Metema-Humera in Northwest Ethiopia as a setting in which we could follow migrant workers when they arrived in an endemic area. The demographic characteristics of this population and factors associated with their risk of asymptomatic infection are poorly characterised. Methods We divided our cohort into individuals who visited this area for the first time (first comers, FC) and those who had already been in this area (repeat comers, RC). We followed them from the beginning (Time 1, T1) to the end of the agricultural season (Time 2, T2), performing tests for sand fly bite exposure (anti-sand fly saliva antibody ELISA) and serology for Leishmania infection (rK39 rapid diagnostic test and the direct agglutination test) at each time point and collecting information on risk factors for infection. Results Our results show that most migrant workers come from non-endemic areas, are male, young (median age of 20 years) and are farmers or students. At T1, >80% of them had been already exposed to sand fly bites, as shown by the presence of anti-saliva antibodies. However, due to seasonality of sand flies there was no difference in exposure between FC and RC, or between T1 and T2. The serology data showed that at T1, but not at T2, a significantly higher proportion of RC were asymptomatic. Furthermore, 28.6% of FC became asymptomatic between T1 and T2. Over the duration of this study, one FC and one RC developed VL. In multivariable logistic regression of asymptomatic infection at T1, only age and the number of visits to Metema/Humera were significantly associated with asymptomatic infection. Conclusion A better understanding of the dynamics of parasite transmission and the risk factors associated with the development of asymptomatic infections and potentially VL will be essential for the development of new strategies to prevent leishmaniasis.
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Affiliation(s)
- Mulat Yimer
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
- Amhara Public Health Institute, Bahir Dar, Ethiopia
| | - Yegnasew Takele
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Endalew Yizengaw
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
- Amhara Public Health Institute, Bahir Dar, Ethiopia
- Institute of Biotechnology, Bahir Dar University, Bahir Dar, Ethiopia
| | - Endalkachew Nibret
- Institute of Biotechnology, Bahir Dar University, Bahir Dar, Ethiopia
- Department of Biology, College of Science, Bahir Dar University, Bahir Dar, Ethiopia
| | - Petra Sumova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | | | - Michael Alehegn
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | - Aileen Rowan
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Ingrid Müller
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - James A. Cotton
- School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Lloyd A. C. Chapman
- Department of Mathematics and Statistics, Lancaster University, Lancaster, United Kingdom
| | - Pascale Kropf
- Department of Infectious Disease, Imperial College London, London, United Kingdom
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Fujimori M, Valencia-Portillo RT, Lindoso JAL, Celeste BJ, de Almeida RP, Costa CHN, da Cruz AM, Druzian AF, Duthie MS, Fortaleza CMCB, de Oliveira ALL, Paniago AMM, Queiroz IT, Reed S, Vallur AC, Goto H, Sanchez MCA. Recombinant protein KR95 as an alternative for serological diagnosis of human visceral leishmaniasis in the Americas. PLoS One 2023; 18:e0282483. [PMID: 36862710 PMCID: PMC9980733 DOI: 10.1371/journal.pone.0282483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 02/15/2023] [Indexed: 03/03/2023] Open
Abstract
In the Americas, visceral leishmaniasis (VL) is caused by the protozoan Leishmania infantum, leading to death if not promptly diagnosed and treated. In Brazil, the disease reaches all regions, and in 2020, 1,933 VL cases were reported with 9.5% lethality. Thus, an accurate diagnosis is essential to provide the appropriate treatment. Serological VL diagnosis is based mainly on immunochromatographic tests, but their performance may vary by location, and evaluation of diagnostic alternatives is necessary. In this study, we aimed to evaluate the performance of ELISA with the scantily studied recombinant antigens, K18 and KR95, comparing their performance with the already known rK28 and rK39. Sera from parasitologically confirmed symptomatic VL patients (n = 90) and healthy endemic controls (n = 90) were submitted to ELISA with rK18 and rKR95. Sensitivity (95% CI) was, respectively, 83.3% (74.2-89.7) and 95.6% (88.8-98.6), and specificity (95% CI) was 93.3% (85.9-97.2) and 97.8% (91.8-99.9). For validation of ELISA with the recombinant antigens, we included samples from 122 VL patients and 83 healthy controls collected in three regions in Brazil (Northeast, Southeast, and Midwest). When comparing the results obtained with the VL patients' samples, significantly lower sensitivity was obtained by rK18-ELISA (88.5%, 95% CI: 81.5-93.2) compared with rK28-ELISA (95.9%, 95% CI: 90.5-98.5), but the sensitivity was similar comparing rKR95-ELISA (95.1%, 95% CI: 89.5-98.0), rK28-ELISA (95.9%, 95% CI: 90.5-98.5), and rK39-ELISA (94.3%, 95% CI: 88.4-97.4). Analyzing the specificity, it was lowest with rK18-ELISA (62.7%, 95% CI: 51.9-72.3) with 83 healthy control samples. Conversely, higher and similar specificity was obtained by rKR95-ELISA (96.4%, 95% CI: 89.5-99.2), rK28-ELISA (95.2%, 95% CI: 87.9-98.5), and rK39-ELISA (95.2%, 95% CI: 87.9-98.5). There was no difference in sensitivity and specificity across localities. Cross-reactivity assessment, performed with sera of patients diagnosed with inflammatory disorders and other infectious diseases, was 34.2% with rK18-ELISA and 3.1% with rKR95-ELISA. Based on these data, we suggest using recombinant antigen KR95 in serological assays for VL diagnosis.
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Affiliation(s)
- Mahyumi Fujimori
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | | | - José Angelo Lauletta Lindoso
- Departamento de Doenças Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Instituto de Infectologia Emílio Ribas, Secretaria de Estado da Saúde, São Paulo, São Paulo, Brazil
| | - Beatriz Julieta Celeste
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Departamento de Medicina Preventiva, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Roque Pacheco de Almeida
- Departamento de Medicina Interna e Patologia, Hospital Universitário/EBSERH, Universidade Federal de Sergipe, Aracaju, Sergipe, Brazil
| | | | - Alda Maria da Cruz
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Angelita Fernandes Druzian
- Faculdade de Medicina, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | | | | | | | | | - Igor Thiago Queiroz
- Hospital Giselda Trigueiro, Secretaria Estadual da Saúde Pública, Natal, Rio Grande do Norte, Brazil
| | - Steve Reed
- HDT Bio, Seattle, Washington, United States of America
| | - Aarthy C. Vallur
- InBios International Inc, Seattle, Washington, United States of America
| | - Hiro Goto
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Departamento de Medicina Preventiva, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Maria Carmen Arroyo Sanchez
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Departamento de Medicina Preventiva, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil
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Singh SS, Chauhan SB, Ng SSS, Corvino D, de Labastida Rivera F, Engel JA, Waddell N, Mukhopadhay P, Johnston RL, Koufariotis LT, Nylen S, Prakash Singh O, Engwerda CR, Kumar R, Sundar S. Increased amphiregulin expression by CD4 + T cells from individuals with asymptomatic Leishmania donovani infection. Clin Transl Immunology 2022; 11:e1396. [PMID: 35663920 PMCID: PMC9136704 DOI: 10.1002/cti2.1396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 04/08/2022] [Accepted: 05/12/2022] [Indexed: 11/10/2022] Open
Abstract
Objectives There is an urgent need to be able to identify individuals with asymptomatic Leishmania donovani infection, so their risk of progressing to VL and transmitting parasites can be managed. This study examined transcriptional markers expressed by CD4+ T cells that could distinguish asymptomatic individuals from endemic controls and visceral leishmaniasis (VL) patients. Methods CD4+ T cells were isolated from individuals with asymptomatic L. donovani infection, endemic controls and VL patients. RNA was extracted and RNAseq employed to identify differentially expressed genes. The expression of one gene and its protein product during asymptomatic infection were evaluated. Results Amphiregulin (AREG) was identified as a distinguishing gene product in CD4+ T cells from individuals with asymptomatic L. donovani infection, compared to VL patients and healthy endemic control individuals. AREG levels in plasma and antigen-stimulated whole-blood assay cell culture supernatants were significantly elevated in asymptomatic individuals, compared to endemic controls and VL patients. Regulatory T (Treg) cells were identified as an important source of AREG amongst CD4+ T-cell subsets in asymptomatic individuals. Conclusion Increased Treg cell AREG expression was identified in individuals with asymptomatic L. donovani infection, suggesting the presence of an ongoing inflammatory response in these individuals required for controlling infection and that AREG may play an important role in preventing inflammation-induced tissue damage and subsequent disease in asymptomatic individuals.
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Affiliation(s)
- Siddharth Sankar Singh
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Shashi Bhushan Chauhan
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Susanna SS Ng
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Institute for Experimental OncologyUniversity of BonnBonnGermany
| | - Dillon Corvino
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Institute for Experimental OncologyUniversity of BonnBonnGermany
| | | | | | - Nic Waddell
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Pamela Mukhopadhay
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Rebecca L Johnston
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Lambros T Koufariotis
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Susanne Nylen
- Department of Microbiology, Tumor and Cell BiologyKarolinska InstituteStockholmSweden
| | | | | | - Rajiv Kumar
- Centre of Experimental Medicine and SurgeryInstitute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
| | - Shyam Sundar
- Department of Medicine, Institute of Medical SciencesBanaras Hindu UniversityVaranasiIndia
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Eyayu T, Yasin M, Workineh L, Tiruneh T, Andualem H, Sema M, Damtie S, Abebaw A, Getie B, Andargie D, Achaw B, Taklual W. Evaluation of urine sample for diagnosis of visceral leishmaniasis using rK-39 immunochromatographic test in Northwest Ethiopia. PLoS One 2022; 17:e0263696. [PMID: 35130316 PMCID: PMC8820633 DOI: 10.1371/journal.pone.0263696] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/24/2022] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Visceral leishmaniasis is the most severe form of leishmaniasis which ranks second in mortality and fourth in morbidity. Parasitological diagnostic techniques with splenic aspirate remain the gold standard. However, sample collection is risky, painful, and difficult. Alternatively, serological techniques provide good diagnostic accuracy using serum sample that is difficult for applying on small children and in the field. So, finding alternative non-invasive and self-collected samples like urine is very important. Thus, the study aimed to evaluate the diagnostic performance of the rK-39 strip test using urine for diagnosis of visceral leishmaniasis. METHODS A multicenter institutional-based cross-sectional study was conducted from November 2019 to March 2021 at Northwest Ethiopia. Sociodemographic information was collected using a structured questionnaire. Blood sample and midstream urine sample were collected for rK-39 test. Data were entered into Epi-data version 4.2 and analyzed using SPSS version 24.0. Diagnostic performance parameters of urine-based rK-39 rapid test, i.e. sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios (LR+/-), and diagnostic accuracy were determined on contingency table by using serum-based rK-39 test result as a reference. An agreement between urine and serum-based rK-39 test was statistically determined by kappa value. RESULT In total, 300 subjects, age ranged between 7 and 60 years, were included in the study. The overall sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of urine-based rK-39 test were found to be 98.0% (95% CI: 93.0% - 99.8%), 95.5% (95% CI: 91.6% - 97.9%), 91.6% (95% CI: 85.2%- 95.4%), 98.9 (95% CI: 96.0%- 99.7%), and 96.33% (95% CI: 93.53-98.16%), respectively. Additionally, there was a strong agreement between the results obtained on rK-39 ICT using urine and serum samples (kappa = 0.92; P < 0.001). CONCLUSION Urine-based rK-39 ICT had an excellent high sensitivity, specificity and strong agreement with serum-based rK-39 ICT results. This indicates that urine sample would be a promising noninvasive and easy to collect sample for diagnosis of VL in field and rural settings.
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Affiliation(s)
- Tahir Eyayu
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Melashu Yasin
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Lemma Workineh
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Tegenaw Tiruneh
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Henok Andualem
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Meslo Sema
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Shewaneh Damtie
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Aynework Abebaw
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Birhanu Getie
- Department of Medical Laboratory Sciences, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Desalegn Andargie
- University of Gondar Compressive Specialized Hospital Laboratory, University of Gondar, Gondar, Ethiopia
| | - Barnabas Achaw
- University of Gondar Compressive Specialized Hospital Laboratory, University of Gondar, Gondar, Ethiopia
| | - Wubet Taklual
- Department of Public Health, College of Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia
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7
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Ibarra-Meneses AV, Corbeil A, Wagner V, Onwuchekwa C, Fernandez-Prada C. Identification of asymptomatic Leishmania infections: a scoping review. Parasit Vectors 2022; 15:5. [PMID: 34983616 PMCID: PMC8727076 DOI: 10.1186/s13071-021-05129-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/11/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Asymptomatic Leishmania infection may play an important role in the transmission of the parasite in endemic areas. At present there is no consensus on the definition of asymptomatic Leishmania infection, nor is there a safe and accessible gold standard test for its identification. METHODS This paper presents a scoping review to summarize definitions of asymptomatic Leishmania infection found in the literature, as well as to detail the approach (molecular, serological, cellular, and/or parasitological tests) used by researchers to identify this asymptomatic population. A scoping review of published and gray literature related to asymptomatic Leishmania infection was conducted; retrieved citations were screened based on predefined eligibility criteria, and relevant data items were extracted from eligible articles. The analysis is descriptive and is presented using tables, figures, and thematic narrative synthesis. RESULTS We conducted a screening of 3008 articles, of which 175 were selected for the full review. Of these articles, we selected 106 that met the inclusion criteria. These articles were published between 1991 and 2021, and in the last 5 years, up to 38 articles were reported. Most of the studies were conducted in Brazil (26%), Spain (14%), India (12%), Bangladesh (10%), and Ethiopia (7%). Of the studies, 84.9% were conducted in the immunocompetent population, while 15.1% were conducted in the immunosuppressed population (HIV, immunosuppressive drugs, and organ transplantation population). We report 14 different techniques and 10 strategies employed by researchers to define asymptomatic Leishmania infection in an endemic area. CONCLUSIONS The definition of asymptomatic Leishmania infection is not unified across the literature, but often includes the following criteria: residence (or extended stay) in a Leishmania-endemic area, no reported signs/symptoms compatible with leishmaniasis, and positive on a combination of serological, molecular, cellular, and/or parasitological tests. Caution is recommended when comparing results of different studies on the subject of asymptomatic infections, as the reported prevalence cannot be confidently compared between areas due to the wide variety of tests employed by research groups. More research on the importance of asymptomatic immunosuppressed and immunocompetent Leishmania-positive populations in leishmaniasis epidemiology is required.
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Affiliation(s)
- Ana Victoria Ibarra-Meneses
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada.,The Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, Université de Montréal, Saint Hyacinthe, Canada
| | - Audrey Corbeil
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada.,The Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, Université de Montréal, Saint Hyacinthe, Canada
| | - Victoria Wagner
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada.,The Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, Université de Montréal, Saint Hyacinthe, Canada
| | - Chukwuemeka Onwuchekwa
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic, University of Barcelona, Barcelona, Spain
| | - Christopher Fernandez-Prada
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada. .,The Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, Université de Montréal, Saint Hyacinthe, Canada.
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8
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Botana L, Ibarra-Meneses AV, Sanchez C, Matia B, San Martin JV, Moreno J, Carrillo E. Leishmaniasis: A new method for confirming cure and detecting asymptomatic infection in patients receiving immunosuppressive treatment for autoimmune disease. PLoS Negl Trop Dis 2021; 15:e0009662. [PMID: 34339445 PMCID: PMC8360552 DOI: 10.1371/journal.pntd.0009662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 08/12/2021] [Accepted: 07/19/2021] [Indexed: 11/19/2022] Open
Abstract
Visceral leishmaniasis (VL) in patients receiving immunosuppressant drugs for autoimmune disease has been on the rise. It is important—but difficult—to know when cure has been achieved in these patients since the withdrawal of immunosuppressants during antileishmania treatment is commonly required, and there is a risk of relapse when immunosuppression is restored. The prevalence of asymptomatic infection among those immunosuppressed for autoimmune disease is also uncertain. The present work describes how cytokine release assays can be used to confirm the cure of VL, and to determine the prevalence of asymptomatic infection, in such patients. After collection of blood from volunteers (n = 108), SLA-stimulation of peripheral blood mononuclear cell cultures and of whole blood was found to induce the production of different combinations of cytokines that served to confirm recovery from VL, and asymptomatic Leishmania infection. Indeed, cure was confirmed in 14 patients, all of whom showed a specific Th1 immune response against Leishmania, and the prevalence of asymptomatic infection was determined as 21.27%. Cytokine profiles could be used to manage VL in patients with autoimmune disease, and to identify and better protect those with asymptomatic infection who are at risk of developing this disease. Cytokine release assays were used to confirm the cure of visceral leishmaniasis in patients (from an area where Leishmania infantum is endemic) with autoimmune disease. They were also used to determine the prevalence of asymptomatic Leishmania infantum infection in similar patients. Some 21.27% of those with no clinical history of leishmaniasis were shown to have been contact with the parasite.
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Affiliation(s)
- Laura Botana
- WHO Collaborating Centre for Leishmaniasis, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda (Madrid), Spain
- Cardiology Department, Universidad Francisco de Vitoria/Hospital Ramón y Cajal Research Unit (IRYCIS), Madrid, Spain
| | - Ana Victoria Ibarra-Meneses
- WHO Collaborating Centre for Leishmaniasis, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda (Madrid), Spain
| | - Carmen Sanchez
- WHO Collaborating Centre for Leishmaniasis, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda (Madrid), Spain
| | - Belen Matia
- Hospital Universitario de Fuenlabrada, Fuenlabrada, Madrid, Spain
| | | | - Javier Moreno
- WHO Collaborating Centre for Leishmaniasis, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda (Madrid), Spain
| | - Eugenia Carrillo
- WHO Collaborating Centre for Leishmaniasis, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda (Madrid), Spain
- * E-mail:
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9
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Fujimori M, de Almeida ADBPF, Barrouin-Melo SM, Cortez LRPDB, Duthie MS, Hiramoto RM, de Pinho FA, Reed SG, Sousa VRF, Souza NF, Soares RM, Tolezano JE, Sanchez MCA, Goto H. Validation of ELISA with recombinant antigens in serological diagnosis of canine Leishmania infantum infection. Mem Inst Oswaldo Cruz 2021; 116:e200428. [PMID: 33729396 PMCID: PMC7968437 DOI: 10.1590/0074-02760200428] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 02/09/2021] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Dogs are the main peridomiciliary reservoir of Leishmania infantum thus the correct diagnosis of infection is essential for the control of the transmission and treatment as well. However, the diagnosis is based on serological assays that are not fully effective. OBJECTIVE We aimed to establish an effective serological assay for the diagnosis of L. infantum infected dogs using Leishmania-derived recombinant antigens. METHODS Leishmania derived rK39-, rK28-, rKR95-based enzyme-linked immunosorbent assay (ELISA) was standardized using symptomatic and asymptomatic L. infantum-infected dogs. Then 2,530 samples from inquiry in endemic areas for VL were evaluated and the results compared with recommended assays by the Brazilian Ministry of Health (MH algorithm). Further samples from a cohort of 30 dogs were searched. FINDINGS For rK39-, rK28- and rKR95-ELISA the sensitivity was around 97% and specificity 100%. The positivity of these three ELISA in the inquiry samples was 27-28%, around 10% higher than the assays currently in use. When cohort samples were searched, we observed likely false-negative results (> 65%) with supposedly negative samples that turned positive six months later with the assays in use (MH algorithm). MAIN CONCLUSIONS For the diagnosis of L. infantum-infected dogs, rK39-based ELISA showed better diagnostic performance than other assays in use in Brazil and worldwide.
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Affiliation(s)
- Mahyumi Fujimori
- Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, SP, Brasil
| | | | - Stella Maria Barrouin-Melo
- Universidade Federal da Bahia, Hospital-Escola de Medicina Veterinária, Laboratório de Infectologia Veterinária, Salvador, BA, Brasil
| | | | | | - Roberto Mitsuyoshi Hiramoto
- Instituto Adolfo Lutz, Centro de Parasitologia e Micologia, Núcleo de Parasitoses Sistêmicas, São Paulo, SP, Brasil
| | - Flaviane Alves de Pinho
- Universidade Federal da Bahia, Hospital-Escola de Medicina Veterinária, Laboratório de Infectologia Veterinária, Salvador, BA, Brasil
| | | | - Valéria Régia Franco Sousa
- Universidade Federal de Mato Grosso, Faculdade de Medicina Veterinária, Departamento de Clínica Médica Veterinária, Cuiabá, MT, Brasil
| | - Nazaré Fonseca Souza
- Universidade Federal Rural da Amazônia, Instituto da Saúde e Produção Animal, Belém, Pará, Brasil
| | - Rodrigo Martins Soares
- Universidade de São Paulo, Faculdade de Medicina Veterinária e Zootecnia, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Laboratório de Doenças Parasitárias, São Paulo, SP, Brasil
| | - José Eduardo Tolezano
- Instituto Adolfo Lutz, Centro de Parasitologia e Micologia, Núcleo de Parasitoses Sistêmicas, São Paulo, SP, Brasil
| | - Maria Carmen Arroyo Sanchez
- Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, SP, Brasil
| | - Hiro Goto
- Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, SP, Brasil
- Universidade de São Paulo, Faculdade de Medicina, Departamento de Medicina Preventiva, São Paulo, SP, Brasil
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10
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Cloots K, Singh OP, Singh AK, Van der Auwera G, Kumar P, Gedda MR, Rai TK, Hasker E, Sundar S, Boelaert M. Assessing L. donovani Skin Parasite Load: A Proof of Concept Study of a Microbiopsy Device in an Indian Setting. Front Cell Infect Microbiol 2021; 11:645121. [PMID: 33791246 PMCID: PMC8006290 DOI: 10.3389/fcimb.2021.645121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/15/2021] [Indexed: 11/22/2022] Open
Abstract
Background In the endgame of the elimination initiative of visceral leishmaniasis (VL) on the Indian subcontinent, one of the main questions remaining is whether asymptomatically infected individuals also contribute to transmission. We piloted a minimally invasive microbiopsy device that could help answer this question. While the potential of this device has been previously illustrated in Ethiopia, no such information is available for the setting of the Indian subcontinent. In this proof of concept study we aimed to assess 1) to what extent skin parasite load obtained with the new microbiopsy device correlates with disease status, 2) to what extent skin parasite load correlates with blood parasite load in the same subject, and 3) to what extent the skin parasite load obtained from different sampling sites on the body correlates with one another. Methods We performed a pilot study in Bihar, India, including 29 VL patients, 28 PKDL patients, 94 asymptomatically infected individuals, 22 endemic controls (EC), and 28 non-endemic controls (NEC). Presence of infection with L. donovani in the blood was assessed using Direct Agglutination Test, rK39 ELISA, Whole Blood Analysis measuring IFN-γ and qPCR. A skin sample was collected with the microbiopsy device on two different locations on the body. PKDL patients provided a third skin sample from the edge of a PKDL lesion. Parasite load in the skin was measured by qPCR. Findings We found a clear correlation between the skin parasite load obtained with the microbiopsy device and disease status, with both higher skin parasite loads and higher proportions of positive skin samples in VL and PKDL patients compared to asymptomatics, EC, and NEC. No clear correlation between skin parasite load and blood parasite load was found, but a moderate correlation was present between the skin parasite load in arm and neck samples. In addition, we found four positive skin samples among asymptomatic individuals, and 85% of PKDL lesions tested positive using this microbiopsy device. Conclusions In line with previous pilot studies, our results from an Indian setting suggest that the microbiopsy device provides a promising tool to measure skin parasite load, and – if validated by xenodiagnosis studies – could facilitate much needed larger scale studies on infectiousness of human subgroups. In addition, we advocate further evaluation of this device as a diagnostic tool for PKDL.
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Affiliation(s)
- Kristien Cloots
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Om Prakash Singh
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India.,Infectious Diseases Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Abhishek Kumar Singh
- Infectious Diseases Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Gert Van der Auwera
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | | | - Mallikarjuna Rao Gedda
- Infectious Diseases Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Tulika Kumari Rai
- Infectious Diseases Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Epco Hasker
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Shyam Sundar
- Infectious Diseases Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Marleen Boelaert
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
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11
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Owen SI, Hossain F, Ghosh P, Chowdhury R, Hossain MS, Jewell C, Cruz I, Picado A, Mondal D, Adams ER. Detection of asymptomatic Leishmania infection in Bangladesh by antibody and antigen diagnostic tools shows an association with post-kala-azar dermal leishmaniasis (PKDL) patients. Parasit Vectors 2021; 14:111. [PMID: 33597000 PMCID: PMC7888088 DOI: 10.1186/s13071-021-04622-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/02/2021] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Asymptomatic Leishmania infections outnumber clinical infections on the Indian subcontinent (ISC), where disease reservoirs are anthroponotic. Diagnostics which detect active asymptomatic infection, which are suitable for monitoring and surveillance, may be of benefit to the visceral leishmaniasis (VL) elimination campaign on the ISC. METHODS Quantitative polymerase chain reaction (qPCR), loop-mediated isothermal amplification (LAMP), and the direct agglutination test (DAT) were carried out on blood samples, and the Leishmania antigen ELISA was carried out on urine samples collected from 720 household and neighbouring contacts of 276 VL and post-kala-azar dermal leishmaniasis (PKDL) index cases, with no symptoms or history of VL or PKDL, in endemic regions of Bangladesh between September 2016 and March 2018. RESULTS Of the 720 contacts of index cases, asymptomatic infection was detected in 69 (9.6%) participants by a combination of qPCR (1.0%), LAMP (2.1%), DAT (3.9%), and Leishmania antigen ELISA (3.3%). Only one (0.1%) participant was detected positive by all four diagnostic tests. Poor agreement between tests was calculated using Cohen's kappa (κ) statistics; however, the Leishmania antigen ELISA and DAT in combination captured all participants as positive by more than one test. We find evidence for a moderately strong association between the index case being a PKDL case (OR 1.94, p = 0.009), specifically macular PKDL (OR 2.12, p = 0.004), and being positive for at least one of the four tests. CONCLUSIONS Leishmania antigen ELISA on urine detects active asymptomatic infection, requires a non-invasive sample, and therefore may be of benefit for monitoring transmission and surveillance in an elimination setting in combination with serology. Development of an antigen detection test in a rapid diagnostic test (RDT) format would be of benefit to the elimination campaign.
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Affiliation(s)
- Sophie I Owen
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine (LSTM), Liverpool, UK
| | - Faria Hossain
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Diseases Research (icddr,b), Dhaka, Bangladesh
| | - Prakash Ghosh
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Diseases Research (icddr,b), Dhaka, Bangladesh
| | - Rajashree Chowdhury
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Diseases Research (icddr,b), Dhaka, Bangladesh
| | - Md Sakhawat Hossain
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Diseases Research (icddr,b), Dhaka, Bangladesh
| | - Chris Jewell
- Lancaster Medical School, Lancaster University, Lancaster, UK
| | - Isra Cruz
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland.,National School of Public Health, Instituto de Salud Carlos III, Madrid, Spain
| | - Albert Picado
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland
| | - Dinesh Mondal
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Diseases Research (icddr,b), Dhaka, Bangladesh
| | - Emily R Adams
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine (LSTM), Liverpool, UK.
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12
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Mannan SB, Elhadad H, Loc TTH, Sadik M, Mohamed MYF, Nam NH, Thuong ND, Hoang-Trong BL, Duc NTM, Hoang AN, Elhusseiny KM, Minh LHN, Quynh TTH, Nghia TLB, Mai Nhu Y, Tieu TM, Hirayama K, Huy NT, Hamano S. Prevalence and associated factors of asymptomatic leishmaniasis: a systematic review and meta-analysis. Parasitol Int 2020; 81:102229. [PMID: 33144197 DOI: 10.1016/j.parint.2020.102229] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 09/19/2020] [Accepted: 10/06/2020] [Indexed: 11/17/2022]
Abstract
Asymptomatic leishmaniasis is believed to play important role in maintaining the transmission of Leishmania spp. within endemic communities. Therefore, the efforts to eliminate leishmaniasis are daunting if we cannot manage asymptomatic leishmaniasis well. To clarify the global prevalence and factors associated with the asymptomatic Leishmania infection, we assessed the prevalence of asymptomatic leishmaniasis by a systematic review followed by meta-analyses. In addition, factors associated with the asymptomatic leishmaniasis versus symptomatic were also analyzed. We included all of the original articles alluding to the human asymptomatic leishmaniasis that was confirmed by at least one laboratory diagnosis method regardless of age, sex, race, and ethnicity of the patients, study design, publication date or languages. In total, 111 original articles were chosen for the data extraction. Based on our meta-analyses of the original articles reporting asymptomatic leishmaniasis mostly in endemic areas, the prevalence of asymptomatic leishmaniasis was 11.2% [95% confidence interval (CI) 8.6%-14.4%] in general population, 36.7% [95% CI 27.6%-46.8%] in inhabitants living in the same or neighboring household to the symptomatic patients, and 11.8% [95% CI 7.1%-19%] in HIV infected patients. Among individuals with leishmaniasis, 64.9% [95% CI 54.7%-73.9%] were asymptomatic and males were more susceptible to develop symptoms, with OR=1.88, 95% CI 1.19-2.99, P=0.007. Meta-regression analysis showed no significant change in the prevalence of asymptomatic leishmaniasis during the last 40 years.
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Affiliation(s)
- Shahnewaj Bin Mannan
- Doctoral Leadership Program, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Heba Elhadad
- Medical Research Institute, Alexandria University, Alexandria 21624, Egypt
| | - Tran Thai Huu Loc
- School of Medicine, Vietnam National University, Ho Chi Minh 700000, Viet Nam; BioTuring Inc, 4445 Eastgate Mall, Suite 200 San Diego, California 92121, USA
| | - Mohamed Sadik
- Faculty of Pharmacy, Al-Azhar University, Cairo 11651, Egypt
| | | | - Nguyen Hai Nam
- Division of Hepato-Biliary-Pancreatic Surgery and Transplantation, Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Nguyen Dinh Thuong
- School of Medicine, Vietnam National University, Ho Chi Minh 700000, Viet Nam
| | - Bao-Long Hoang-Trong
- Faculty of Medicine, Pham Ngoc Thach University of Medicine, Ho Chi Minh 70000, Viet Nam
| | - Nguyen Tran Minh Duc
- Faculty of Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh 700000, Viet Nam
| | - An Nguyen Hoang
- Faculty of Medicine, Pham Ngoc Thach University of Medicine, Ho Chi Minh 70000, Viet Nam
| | | | - Le Huu Nhat Minh
- Faculty of Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh 700000, Viet Nam
| | | | - Thai Le Ba Nghia
- Department of Biomedical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, United States
| | - Y Mai Nhu
- Department of Chemical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, United States
| | | | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
| | - Nguyen Tien Huy
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam; School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki 852-8523, Japan.
| | - Shinjiro Hamano
- Doctoral Leadership Program, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; The Joint Usage/Research Center on Tropical Disease, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
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13
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Mollett G, Bremer Hinckel BC, Bhattacharyya T, Marlais T, Singh OP, Mertens P, Falconar AK, El-Safi S, Sundar S, Miles MA. Detection of Immunoglobulin G1 Against rK39 Improves Monitoring of Treatment Outcomes in Visceral Leishmaniasis. Clin Infect Dis 2020; 69:1130-1135. [PMID: 30541022 PMCID: PMC6743847 DOI: 10.1093/cid/ciy1062] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/07/2018] [Indexed: 11/15/2022] Open
Abstract
Background Visceral leishmaniasis (VL), caused by the Leishmania donovani complex, is a fatal, neglected tropical disease that is targeted for elimination in India, Nepal, and Bangladesh. Improved diagnostic tests are required for early case detection and for monitoring the outcomes of treatments. Previous investigations using Leishmania lysate antigen demonstrated that the immunoglobulin (Ig) G1 response is a potential indicator of a patient’s clinical status after chemotherapy. Methods IgG1 or IgG enzyme-linked immunosorbent assays (ELISAs) with rK39 or lysate antigens and novel IgG1 rK39 rapid diagnostic tests (RDTs) were assessed with Indian VL serum samples from the following clinical groups: paired pre- and postchemotherapy (deemed cured); relapsed; other infectious diseases; and endemic, healthy controls. Results With paired pre- and post-treatment samples (n = 37 pairs), ELISAs with rK39- and IgG1-specific conjugates gave a far more discriminative decrease in post-treatment antibody responses when compared to IgG (P < .0001). Novel IgG1 rK39 RDTs provided strong evidence for decreased IgG1 responses in patients who had successful treatment (P < .0001). Furthermore, both IgG1 rK39 RDTs (n = 38) and ELISAs showed a highly significant difference in test outcomes between cured patients and those who relapsed (n = 23; P < .0001). RDTs were more sensitive than corresponding ELISAs. Conclusions We present strong evidence for the use of IgG1 in monitoring treatment outcomes in VL, and the first use of an IgG1-based RDT using the rK39 antigen for the discrimination of post-treatment cure versus relapse in VL. Such an RDT may have a significant role in monitoring patients and in targeted control and elimination of this devastating disease.
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Affiliation(s)
- Guy Mollett
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Bruno C Bremer Hinckel
- Coris BioConcept, Gembloux.,Department of Biomedical Sciences, University of Antwerp, Belgium
| | - Tapan Bhattacharyya
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Tegwen Marlais
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Om Prakash Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | | | - Andrew K Falconar
- Departamento de Medicina, Universidad del Norte, Barranquilla, Colombia
| | | | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Michael A Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
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14
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Conversion of asymptomatic infection to symptomatic visceral leishmaniasis: A study of possible immunological markers. PLoS Negl Trop Dis 2020; 14:e0008272. [PMID: 32555598 PMCID: PMC7326279 DOI: 10.1371/journal.pntd.0008272] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 06/30/2020] [Accepted: 04/07/2020] [Indexed: 12/31/2022] Open
Abstract
Introduction Presence of asymptomatic individuals in endemic areas is common. The possible biomarkers in asymptomatic individuals once they get exposed to infection as well as following conversion to symptomatic disease are yet to be identified.We identified asymptomatic Visceral leishmaniasis (VL) infection amongst rK39+sorted direct agglutination test positive (DAT+) endemic healthy population and confirmed it by quantitative PCR(qPCR).The immunological determinants such as Adenosine deaminase (ADA), Interferon gamma (IFN-γ), Tumour Necrosis Factor alpha (TNF-α) and Interleukin 10 (IL-10)were examined to predict probable biomarkers for conversion to symptomatic VL. Methods Sample size was 5794 healthy individuals from VL endemic region. Antibody tests(DAT &rK39) were performed and later a qPCR assay was employed using kDNA specific primers and probes. Immunological biomarkers examined were ADA level by ADA–MTP kit and quantitative cytokines(IFN-γ, IL-10 and TNF-α) by ELISA. Results 120 asymptomatic individuals of 308 rK39 sero-positives were DAT positive comprising of 56 with previous history and 64 with no history of VL. RT-PCR confirmed asymptomatic VL in 42 sero-positives. These were followed up through repeated qPCR and evaluation of immunological determinants. We observed10 symptomatic cases converted from a total of 42 asymptomatic individuals identified at base-line. The level of ADA, IL-10 and IFN-γ remained consistently high in asymptomatic cases and amongst these, ADA and IL-10 but not IFN-γ remained higher at the development of clinical symptoms into active VL. On the contrary, there was no significant change in the mean concentration of TNF-α at both stages of the disease. Discussion We surmise from our data that considerable proportion of asymptomatic cases can be a reservoir and may play a crucial role in transmission of visceral leishmaniasis in endemic areas. The data also suggests that ADA and IL-10 can serve as a potential biomarker during the conversion of asymptomatic into symptomatic VL. The most threatening form of leishmaniasis is human visceral leishmaniasis, which is caused by L. donovani in Indian subcontinent. The disease accounts for huge annual burden of infectious disease in India. Efforts towards disease elimination programme are far beyond satisfaction and there is need to re-strengthen health monitoring, surveillance programme in endemic areas. There is a greater need to identify asymptomatic individuals amongst endemic healthy control by active surveillance programme. Further, except a few, many asymptomatic subjects become sero-negative without developing VL due to strong inherent cellular immunity possessed by them. This study enumerates use of rK39, DAT and quantitative PCR(qPCR) in asymptomatic detection and then evaluate immunological biomarkers(Adenosine deaminase, IFN-γ, TNF-α and IL-10) which help in disease conversion to symptomatic VL, at 6 month follow- up. Follow–up analysis revealed that antibody testing with rK39 (3.24%), DAT (8.33%) had poor agreement with disease conversion. By qPCR, we could identify the level of parasitemia, and collectively with serology, the test detected 23.80% of asymptomatic cases converted into disease. The level of ADA and IL-10 remained consistently high during conversion. IFN-γ became high in asymptomatic infection but became low on conversion, whereas, no significant change in level of TNF-α was observed at both stages of disease. Thus by use of qPCR, concomitantly with DAT over rK39+ sorted endemic healthy control may be employed for early case detection. Adenosine is produced by ecto-nucleotide during L.donovaniinfection, has been previously reported and in parallel to this study we conclude that determination of adenosine deaminase level (ADA) might help identify early cases with more tendency to convert into disease. This will help to boost health monitoring programme to eradicate Kala-azar in Bihar, India.
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15
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Alvar J, Alves F, Bucheton B, Burrows L, Büscher P, Carrillo E, Felger I, Hübner MP, Moreno J, Pinazo MJ, Ribeiro I, Sosa-Estani S, Specht S, Tarral A, Wourgaft NS, Bilbe G. Implications of asymptomatic infection for the natural history of selected parasitic tropical diseases. Semin Immunopathol 2020; 42:231-246. [PMID: 32189034 PMCID: PMC7299918 DOI: 10.1007/s00281-020-00796-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 03/03/2020] [Indexed: 12/18/2022]
Abstract
Progress has been made in the control or elimination of tropical diseases, with a significant reduction of incidence. However, there is a risk of re-emergence if the factors fueling transmission are not dealt with. Although it is essential to understand these underlying factors for each disease, asymptomatic carriers are a common element that may promote resurgence; their impact in terms of proportion in the population and role in transmission needs to be determined. In this paper, we review the current evidence on whether or not to treat asymptomatic carriers given the relevance of their role in the transmission of a specific disease, the efficacy and toxicity of existing drugs, the Public Health interest, and the benefit at an individual level, for example, in Chagas disease, to prevent irreversible organ damage. In the absence of other control tools such as vaccines, there is a need for safer drugs with good risk/benefit profiles in order to change the paradigm so that it addresses the complete infectious process beyond manifest disease to include treatment of non-symptomatic infected persons.
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Affiliation(s)
- Jorge Alvar
- Drugs for Neglected Diseases initiative, Geneva, Switzerland.
| | - Fabiana Alves
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | - Bruno Bucheton
- Institut de Recherche pour le Développement, Université de Montpellier, Montpellier, France
| | - Louise Burrows
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | | | - Eugenia Carrillo
- WHO Collaborating Cenre for Leishmaniasis, Instituto de Sakud Carlos III, Madrid, Spain
| | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Marc P Hübner
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Javier Moreno
- WHO Collaborating Cenre for Leishmaniasis, Instituto de Sakud Carlos III, Madrid, Spain
| | | | - Isabela Ribeiro
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | - Sergio Sosa-Estani
- Drugs for Neglected Diseases initiative, Centro de Investigación de Epidemiología y Salud Pública (CIESP-IECS), CONICET, Buenos Aires, Argentina
| | - Sabine Specht
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | - Antoine Tarral
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
| | | | - Graeme Bilbe
- Drugs for Neglected Diseases initiative, Geneva, Switzerland
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Longitudinal evaluation of asymptomatic Leishmania infection in HIV-infected individuals in North-West Ethiopia: A pilot study. PLoS Negl Trop Dis 2019; 13:e0007765. [PMID: 31593563 PMCID: PMC6799935 DOI: 10.1371/journal.pntd.0007765] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 10/18/2019] [Accepted: 09/09/2019] [Indexed: 12/13/2022] Open
Abstract
Background In endemic regions, asymptomatic Leishmania infection is common. In HIV patients, detection of asymptomatic Leishmania infection could potentially identify those at risk of visceral leishmaniasis (VL). However, data on the prevalence, incidence, and determinants of asymptomatic infection, and the risk of VL are lacking. Methods We conducted a cross-sectional survey at a single ART centre, followed by a prospective cohort study amongst HIV-infected adults in HIV care in a district hospital in a VL-endemic area in North-West Ethiopia (9/2015-8/2016). Asymptomatic Leishmania infection was detected using the direct agglutination test (DAT), rK39-rapid diagnostic test (RDT)), PCR on peripheral blood and the KAtex urine antigen test, and defined as positivity on any Leishmania marker. All individuals were followed longitudinally (irrespective of the Leishmania test results). Risk factors for asymptomatic Leishmania infection were determined using logistic regression. Results A total of 534 HIV-infected individuals enrolled in HIV care were included in the study. After excluding 13 patients with a history of VL and an 10 patients with incomplete baseline Leishmania tests, 511 were included in analysis. The median age was 38 years (interquartile range (IQR) 30–45), 62.6% were male. The median follow-up time was 12 months (IQR 9–12). No deaths were reported during the study period. Most (95.5%) were on antiretroviral treatment at enrolment, for a median of 52 months (IQR 27–79). The median CD4 count at enrolment was 377 cells/mm3 (IQR 250–518). The baseline prevalence of Leishmania infection was 12.8% in males and 4.2% in females. Overall, 7.4% tested positive for rK39, 4.3% for DAT, 0.2% for PCR and 0.2% for KAtex. Independent risk factors for a prevalent infection were male sex (odds ratio (OR) 3.2; 95% confidence intervals (CI) 14–7.0) and concurrent malaria infection (OR 6.1; 95% CI 1.9–18.9). Amongst the 49 prevalent (baseline) infections with further follow-up, the cumulative incidence of losing the Leishmania markers by one year was 40.1%. There were 36 incident infections during the course of the study, with a cumulative one-year risk of 9.5%. Only one case of VL was detected during follow-up. Conclusions We found a high prevalence of asymptomatic Leishmania infection, persisting in most cases. The incidence was more modest and overt VL was rare. Larger and longer studies with more complete follow-up may help to decide whether a test and treat strategy would be justified in this context. Trial registration ClinicalTrials.gov NCT02839603 As visceral leishmaniasis (VL) in HIV patients is difficult to treat and associated with high mortality, strategies to detect and treat asymptomatic Leishmania infection in HIV patients should be explored. However, data on the prevalence, incidence, determinants of asymptomatic infection and risk of VL are lacking. We conducted a longitudinal study, including HIV-infected adult patients in HIV care in a district hospital in a VL-endemic area in North-West Ethiopia. Asymptomatic Leishmania infection was evaluated by Leishmania antibody tests (DAT and rK39), urine antigen tests (KAtex) and PCR, and was defined as positivity on any Leishmania marker. We also looked for independent risk factors for asymptomatic Leishmania infection at study recruitment. A total of 511 patients were included in the analysis. The median age was 38 years, 62.6% were male. The median time of residence in a VL-endemic area was 18 years. Most (95.5%) were on antiretroviral treatment at enrolment, for a median of 52 months. The median CD4 count at enrolment was 377 cells/mm3. The baseline prevalence of Leishmania infection was 12.8% in males and 4.2% in females. Overall, 7.4% tested positive for rK39, 4.3% for DAT, 0.2% for PCR and 0.2% for KAtex. Independent risk factors for a prevalent infection were male sex and concurrent malaria infection. Amongst the 49 prevalent infections that were present upon enrolment in the study, the probability of losing the Leishmania markers by one year was 40.1%. There were 36 new infections during the course of the study, with an overall risk of 9.5% by one year of follow-up. One case of VL was detected during follow-up. In conclusion, we found a high prevalence of asymptomatic Leishmania infection, which persisted in most cases. The incidence was more modest. Larger and longer studies would be needed to decide whether a test and treat strategy would be justified in this context.
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Toghueo RMK. Anti-leishmanial and Anti-inflammatory Agents from Endophytes: A Review. NATURAL PRODUCTS AND BIOPROSPECTING 2019; 9:311-328. [PMID: 31564050 PMCID: PMC6814666 DOI: 10.1007/s13659-019-00220-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 09/23/2019] [Indexed: 05/05/2023]
Abstract
Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year. The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective medicines, the resistance, and the toxicity of available drugs. On the other hand, many drugs are used for the management of inflammatory disorders. However, the most commonly prescribed although efficient is highly toxic with multiples side effects. New leads compounds for the development of new anti-leishmanial and anti-inflammatory drugs are needed. Over the past decade, several studies on the potential of endophytes to produce bioactive metabolites have been reported. We are presenting in the present review the status of research from 2000 to 2019 on the anti-leishmanial and anti-inflammatory metabolites isolated from endophytes from diverse habitats. An emphasis was put on existing gaps in the literature to inspire and guide future investigations. We hope that this review will help accelerate the drug discovery against leishmaniases and inflammation-associated disorders.
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Affiliation(s)
- Rufin Marie Kouipou Toghueo
- Antimicrobial and Biocontrol Agents Unit (AmBcAU), Laboratory for Phytobiochemistry and Medicinal Plants Studies, Department of Biochemistry, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.
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Fakiola M, Singh OP, Syn G, Singh T, Singh B, Chakravarty J, Sundar S, Blackwell JM. Transcriptional blood signatures for active and amphotericin B treated visceral leishmaniasis in India. PLoS Negl Trop Dis 2019; 13:e0007673. [PMID: 31419223 PMCID: PMC6713396 DOI: 10.1371/journal.pntd.0007673] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 08/28/2019] [Accepted: 07/30/2019] [Indexed: 12/13/2022] Open
Abstract
Amphotericin B provides improved therapy for visceral leishmaniasis (VL) caused by Leishmania donovani, with single dose liposomal-encapsulated Ambisome providing the best cure rates. The VL elimination program aims to reduce the incidence rate in the Indian subcontinent to <1/10,000 population/year. Ability to predict which asymptomatic individuals (e.g. anti-leishmanial IgG and/or Leishmania-specific modified Quantiferon positive) will progress to clinical VL would help in monitoring disease outbreaks. Here we examined whole blood transcriptional profiles associated with asymptomatic infection, active disease, and in treated cases. Two independent microarray experiments were performed, with analysis focussed primarily on differentially expressed genes (DEGs) concordant across both experiments. No DEGs were identified for IgG or Quantiferon positive asymptomatic groups compared to negative healthy endemic controls. We therefore concentrated on comparing concordant DEGs from active cases with all healthy controls, and in examining differences in the transcriptome following different regimens of drug treatment. In these comparisons 6 major themes emerged: (i) expression of genes and enrichment of gene sets associated with erythrocyte function in active cases; (ii) strong evidence for enrichment of gene sets involved in cell cycle in comparing active cases with healthy controls; (iii) identification of IFNG encoding interferon-γ as the major hub gene in concordant gene expression patterns across experiments comparing active cases with healthy controls or with treated cases; (iv) enrichment for interleukin signalling (IL-1/3/4/6/7/8) and a prominent role for CXCL10/9/11 and chemokine signalling pathways in comparing active cases with treated cases; (v) the novel identification of Aryl Hydrocarbon Receptor signalling as a significant canonical pathway when comparing active cases with healthy controls or with treated cases; and (vi) global expression profiling support for more effective cure at day 30 post-treatment with a single dose of liposomal encapsulated amphotericin B compared to multi-dose non-liposomal amphotericin B treatment over 30 days. (296 words; 300 words allowed).
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Affiliation(s)
- Michaela Fakiola
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- INGM-National Institute of Molecular Genetics "Romeo ed Enrica Invernizzi" Milan, Milan, Italy
| | - Om Prakash Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Genevieve Syn
- Telethon Kids Institute, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Toolika Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Bhawana Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Jaya Chakravarty
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Jenefer M. Blackwell
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- Telethon Kids Institute, The University of Western Australia, Nedlands, Western Australia, Australia
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Asymptomatic immune responders to Leishmania among HIV positive patients. PLoS Negl Trop Dis 2019; 13:e0007461. [PMID: 31158223 PMCID: PMC6564048 DOI: 10.1371/journal.pntd.0007461] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 06/13/2019] [Accepted: 05/13/2019] [Indexed: 12/14/2022] Open
Abstract
Concomitant infection with human immunodeficiency virus (HIV) and the Leishmania parasite is a growing public health problem, the result of the former spreading to areas where the latter is endemic. Leishmania infection is usually asymptomatic in immunocompetent individuals, but the proportion of HIV+ individuals in contact with the parasite who remain asymptomatic is not known. The aim of the present work was to examine the use of cytokine release assays in the detection of asymptomatic immune responders to Leishmania among HIV+ patients with no previous leishmaniasis or current symptomatology. Eighty two HIV+ patients (all from Fuenlabrada, Madrid, Spain, where a leishmaniasis outbreak occurred in 2009) were examined for Leishmania infantum infection using molecular and humoral response-based methods. None returned a positive molecular or serological result for the parasite. Thirteen subjects showed a positive lymphoproliferative response to soluble Leishmania antigen (SLA), although the mean CD4+ T lymphocyte counts of these patients was below the normal range. Stimulation of peripheral blood mononuclear cells (PBMC) or whole blood with SLA (the lymphoproliferative assay and whole blood assay respectively), led to the production of specific cytokines and chemokines. Thus, despite being immunocompromised, HIV+ patients can maintain a Th1-type cellular response to Leishmania. In addition, cytokine release assays would appear to be useful tools for detecting these individuals via the identification of IFN-γ in the supernatants of SLA-stimulated PBMC, and of IFN-γ, MIG and IL-2 in SLA-stimulated whole blood. These biomarkers appear to be 100% reliable for detecting asymptomatic immune responders to Leishmania among HIV+ patients. The proportion of patients with HIV+ who have at some time been infected with the Leishmania parasite, but who remain asymptomatic, is unknown. It is important to be able to identify such patients to determine the prevalence of asymptomatic leishmaniasis in the HIV+ population, and because these persons are at increased risk of developing symptomatic visceral leishmaniasis. In the present work, a population of HIV+ patients showing a cellular immune response to Leishmania infantum was identified. These subjects all showed a clear Th1-type response when their PBMC or blood were stimulated in vitro with soluble Leishmania antigen (SLA). Cytokine release assays and the detection of IFN-γ, MIG and IL-2 (specific biomarkers for immunity to Leishmania) were found to be useful for detecting this population of HIV+ patients. New studies with larger numbers of patients are needed to confirm the present results.
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Determinants for progression from asymptomatic infection to symptomatic visceral leishmaniasis: A cohort study. PLoS Negl Trop Dis 2019; 13:e0007216. [PMID: 30917114 PMCID: PMC6453476 DOI: 10.1371/journal.pntd.0007216] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 04/08/2019] [Accepted: 02/05/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Asymptomatic Leishmania donovani infections outnumber clinical presentations, however the predictors for development of active disease are not well known. We aimed to identify serological, immunological and genetic markers for progression from L. donovani infection to clinical Visceral Leishmaniasis (VL). METHODS We enrolled all residents >2 years of age in 27 VL endemic villages in Bihar (India). Blood samples collected on filter paper on two occasions 6-12 months apart, were tested for antibodies against L. donovani with rK39-ELISA and DAT. Sero converters, (negative for both tests in the first round but positive on either of the two during the second round) and controls (negative on both tests on both occasions) were followed for three years. At the start of follow-up venous blood was collected for the following tests: DAT, rK39- ELISA, Quantiferon assay, SNP/HLA genotyping and L.donovani specific quantitative PCR. RESULTS Among 1,606 subjects enrolled,17 (8/476 seroconverters and 9/1,130 controls) developed VL (OR 3.1; 95% CI 1.1-8.3). High DAT and rK39 ELISA antibody titers as well as positive qPCR were strongly and significantly associated with progression from seroconversion to VL with odds ratios of 19.1, 30.3 and 20.9 respectively. Most VL cases arose early (median 5 months) during follow-up. CONCLUSION We confirmed the strong association between high DAT and/or rK39 titers and progression to disease among asymptomatic subjects and identified qPCR as an additional predictor. Low predictive values do not warrant prophylactic treatment but as most progressed to VL early during follow-up, careful oberservation of these subjects for at least 6 months is indicated.
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Mishra A, Sundaravadivel P, Tripathi SK, Jha RK, Badrukhiya J, Basak N, Anerao I, Sharma A, Idowu AE, Mishra A, Pandey S, Kumar U, Singh S, Nizamuddin S, Tupperwar NC, Jha AN, Thangaraj K. Variations in macrophage migration inhibitory factor gene are not associated with visceral leishmaniasis in India. J Infect Public Health 2019; 12:380-387. [PMID: 30611734 DOI: 10.1016/j.jiph.2018.12.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 11/24/2018] [Accepted: 12/17/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The host genetic factors play important role in determining the outcome of visceral leishmaniasis (VL). Macrophage migration inhibitory factor (MIF) is an important host cytokine, which is a key regulator of innate immune system. Genetic variants in MIF gene have been found to be associated with several inflammatory and infectious diseases. Role of MIF is well documented in leishmaniasis diseases, including Indian visceral leishmaniasis, where elevated level of serum MIF has been associated with VL phenotypes. However, there was no genetic study to correlate MIF variants in VL, therefore, we aimed to study the possible association of three reported MIF gene variants -794 CATT, -173G > C and non-coding RNA gene LOC284889 in Indian VL phenotype. METHODS Study subjects comprised of 214 VL patients along with ethnically and demographically matched 220 controls from VL endemic regions of Bihar state in India. RESULTS We found no significant difference between cases and controls in allelic, genotypic and haplotype frequency of the markers analysed [-794 CATT repeats (χ2=0.86; p=0.35; OR=0.85; 95% CI=0.61-1.19); -173 G>C polymorphism (χ2=1.11; p=0.29; OR=0.83; 95% CI=0.59-1.16); and LOC284889 (χ2=0.78; p=0.37; OR=0.86; 95% CI=0.61-1.20)]. CONCLUSION Since we did not find any significant differences between case and control groups, we conclude that sequencing of complete MIF gene and extensive study on innate and adaptive immunity genes may help in identifying genetic variations that are associated with VL susceptibility/resistance among Indians.
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Affiliation(s)
- Anshuman Mishra
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India; Vinoba Bhave Research Institute, Allahabad, India; Institute of Advanced Materials, Linkoping, Sweden
| | | | | | - Rajan Kumar Jha
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Nipa Basak
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India; Academy of Scientific and Innovative Research, India
| | - Isha Anerao
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Akshay Sharma
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Ajayi Ebenezer Idowu
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India; Osun State University, Oshogbo, Nigeria
| | | | | | - Umesh Kumar
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Sakshi Singh
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | | | - Aditya Nath Jha
- CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India; Sickle Cell Institute Chhattisgarh, Raipur, India
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Marlais T, Bhattacharyya T, Singh OP, Mertens P, Gilleman Q, Thunissen C, Hinckel BCB, Pearson C, Gardner BL, Airs S, de la Roche M, Hayes K, Hafezi H, Falconar AK, Eisa O, Saad A, Khanal B, Bhattarai NR, Rijal S, Boelaert M, El-Safi S, Sundar S, Miles MA. Visceral Leishmaniasis IgG1 Rapid Monitoring of Cure vs. Relapse, and Potential for Diagnosis of Post Kala-Azar Dermal Leishmaniasis. Front Cell Infect Microbiol 2018; 8:427. [PMID: 30619774 PMCID: PMC6300496 DOI: 10.3389/fcimb.2018.00427] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 11/28/2018] [Indexed: 01/13/2023] Open
Abstract
Background: There is a recognized need for an improved diagnostic test to assess post-chemotherapeutic treatment outcome in visceral leishmaniasis (VL) and to diagnose post kala-azar dermal leishmaniasis (PKDL). We previously demonstrated by ELISA and a prototype novel rapid diagnostic test (RDT), that high anti-Leishmania IgG1 is associated with post-treatment relapse versus cure in VL. Methodology: Here, we further evaluate this novel, low-cost RDT, named VL Sero K-SeT, and ELISA for monitoring IgG1 levels in VL patients after treatment. IgG1 levels against L. donovani lysate were determined. We applied these assays to Indian sera from cured VL at 6 months post treatment as well as to relapse and PKDL patients. Sudanese sera from pre- and post-treatment and relapse were also tested. Results: Of 104 paired Indian sera taken before and after treatment for VL, when deemed clinically cured, 81 (77.9%) were positive by VL Sero K-SeT before treatment; by 6 months, 68 of these 81 (84.0%) had a negative or reduced RDT test line intensity. ELISAs differed in positivity rate between pre- and post-treatment (p = 0.0162). Twenty eight of 33 (84.8%) Indian samples taken at diagnosis of relapse were RDT positive. A comparison of Indian VL Sero K-SeT data from patients deemed cured and relapsed confirmed that there was a significant difference (p < 0.0001) in positivity rate for the two groups using this RDT. Ten of 17 (58.8%) Sudanese sera went from positive to negative or decreased VL Sero K-SeT at the end of 11–30 days of treatment. Forty nine of 63 (77.8%) PKDL samples from India were positive by VL Sero K-SeT. Conclusion: We have further shown the relevance of IgG1 in determining clinical status in VL patients. A positive VL Sero K-SeT may also be helpful in supporting diagnosis of PKDL. With further refinement, such as the use of specific antigens, the VL Sero K-SeT and/or IgG1 ELISA may be adjuncts to current VL control programmes.
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Affiliation(s)
- Tegwen Marlais
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Tapan Bhattacharyya
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Om Prakash Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University Varanasi, India
| | | | | | | | - Bruno C Bremer Hinckel
- Coris BioConcept Gembloux, Belgium.,Department of Biomedical Sciences, University of Antwerp Antwerp, Belgium
| | - Callum Pearson
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Bathsheba L Gardner
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Stephanie Airs
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Marianne de la Roche
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Kiera Hayes
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Hannah Hafezi
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
| | - Andrew K Falconar
- Departamento de Medicina, Universidad del Norte Barranquilla, Colombia
| | - Osama Eisa
- Faculty of Medicine, University of Khartoum Khartoum, Sudan
| | | | - Basudha Khanal
- Department of Microbiology, B.P. Koirala Institute of Health Sciences Dharan, Nepal
| | | | - Suman Rijal
- Department of Internal Medicine, B.P. Koirala Institute of Health Sciences Dharan, Nepal
| | - Marleen Boelaert
- Department of Public Health, Institute of Tropical Medicine Antwerp, Belgium
| | - Sayda El-Safi
- Faculty of Medicine, University of Khartoum Khartoum, Sudan
| | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University Varanasi, India
| | - Michael A Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, United Kingdom
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Chapman LAC, Morgan ALK, Adams ER, Bern C, Medley GF, Hollingsworth TD. Age trends in asymptomatic and symptomatic Leishmania donovani infection in the Indian subcontinent: A review and analysis of data from diagnostic and epidemiological studies. PLoS Negl Trop Dis 2018; 12:e0006803. [PMID: 30521526 PMCID: PMC6283524 DOI: 10.1371/journal.pntd.0006803] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 08/30/2018] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Age patterns in asymptomatic and symptomatic infection with Leishmania donovani, the causative agent of visceral leishmaniasis (VL) in the Indian subcontinent (ISC), are currently poorly understood. Age-stratified serology and infection incidence have been used to assess transmission levels of other diseases, which suggests that they may also be of use for monitoring and targeting control programmes to achieve elimination of VL and should be included in VL transmission dynamic models. We therefore analysed available age-stratified data on both disease incidence and prevalence of immune markers with the aim of collating the currently available data, estimating rates of infection, and informing modelling and future data collection. METHODOLOGY/PRINCIPAL FINDINGS A systematic literature search yielded 13 infection prevalence and 7 VL incidence studies meeting the inclusion criteria. Statistical tests were performed to identify trends by age, and according to diagnostic cut-off. Simple reversible catalytic models with age-independent and age-dependent infection rates were fitted to the prevalence data to estimate infection and reversion rates, and to test different hypotheses about the origin of variation in these rates. Most of the studies showed an increase in infection prevalence with age: from ≲10% seroprevalence (<20% Leishmanin skin test (LST) positivity) for 0-10-year-olds to >10% seroprevalence (>20% LST-positivity) for 30-40-year-olds, but overall prevalence varied considerably between studies. VL incidence was lower amongst 0-5-year-olds than older age groups in most studies; most showing a peak in incidence between ages 5 and 20. The age-independent catalytic model provided the best overall fit to the infection prevalence data, but the estimated rates for the less parsimonious age-dependent model were much closer to estimates from longitudinal studies, suggesting that infection rates may increase with age. CONCLUSIONS/SIGNIFICANCE Age patterns in asymptomatic infection prevalence and VL incidence in the ISC vary considerably with geographical location and time period. The increase in infection prevalence with age and peaked age-VL-incidence distribution may be due to lower exposure to infectious sandfly bites in young children, but also suggest that acquired immunity to the parasite increases with age. However, poor standardisation of serological tests makes it difficult to compare data from different studies and draw firm conclusions about drivers of variation in observed age patterns.
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Affiliation(s)
- Lloyd A. C. Chapman
- Zeeman Institute, University of Warwick, Coventry, United Kingdom
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Alex L. K. Morgan
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- School of Biological Sciences, University of Edinburgh, Edinbugh, United Kingdom
| | - Emily R. Adams
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Caryn Bern
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America
| | - Graham F. Medley
- Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - T. Déirdre Hollingsworth
- Zeeman Institute, University of Warwick, Coventry, United Kingdom
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, United Kingdom
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Sundar S, Singh OP, Chakravarty J. Visceral leishmaniasis elimination targets in India, strategies for preventing resurgence. Expert Rev Anti Infect Ther 2018; 16:805-812. [PMID: 30289007 DOI: 10.1080/14787210.2018.1532790] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Visceral leishmaniasis (VL) is a fatal parasitic disease caused by a parasite belonging to the Leishmania donovani complex and transmitted by infected female Phlebotomous argentipes sand flies. The VL elimination strategy in the Indian subcontinent (ISC), which has a current goal of reducing the incidence of VL to below 1/10,000 of population by the year 2020, consists of rapid detection and treatment of VL to reduce the number of human reservoirs as well as vector control using indoor residual spraying (IRS). However, as the incidence of VL declines toward the elimination goal, greater targeting of control methods will be required to ensure appropriate early action to prevent the resurgence of VL. Area covered: We discuss the current progress and challenges in the VL elimination program and strategies to be employed to ensure sustained elimination of VL. Expert commentary: The VL elimination initiative has saved many human lives; however, for VL elimination to become a reality in a sustained way, an intense effort is needed, as substantial numbers of endemic subdistricts (primary health centers (PHCs) blocks level) are yet to reach the elimination target. In addition to effective epidemiological surveillance, appropriate diagnostic and treatment services for VL at PHCs will be needed to ensure long-term sustainability and prevent reemergence of VL.
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Affiliation(s)
- Shyam Sundar
- a Department of Medicine , Institute of Medical Sciences, Banaras Hindu University , Varanasi , India
| | - Om Prakash Singh
- a Department of Medicine , Institute of Medical Sciences, Banaras Hindu University , Varanasi , India
| | - Jaya Chakravarty
- a Department of Medicine , Institute of Medical Sciences, Banaras Hindu University , Varanasi , India
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Saha P, Ganguly S, Chatterjee M, Das SB, Kundu PK, Guha SK, Ghosh TK, Bera DK, Basu N, Maji AK. Asymptomatic leishmaniasis in kala-azar endemic areas of Malda district, West Bengal, India. PLoS Negl Trop Dis 2017; 11:e0005391. [PMID: 28187202 PMCID: PMC5322936 DOI: 10.1371/journal.pntd.0005391] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 02/23/2017] [Accepted: 02/06/2017] [Indexed: 11/18/2022] Open
Abstract
Asymptomatic leishmaniasis may drive the epidemic and an important challenge to reach the goal of joint Visceral Leishmaniasis (VL) elimination initiative taken by three Asian countries. The role of these asymptomatic carriers in disease transmission, prognosis at individual level and rate of transformation to symptomatic VL/Post Kala-azar Dermal Leishmaniasis (PKDL) needs to be evaluated. Asymptomatic cases were diagnosed by active mass survey in eight tribal villages by detecting antileishmanial antibody using rK39 based rapid diagnostic kits and followed up for three years to observe the pattern of sero-conversion and disease transformation. Out of 2890 total population, 2603 were screened. Antileishmanial antibody was detected in 185 individuals of them 96 had a history of VL/PKDL and 89 without such history. Seventy nine such individuals were classified as asymptomatic leishmaniasis and ten as active VL with a ratio of 7.9:1. Out of 79 asymptomatic cases 2 were lost to follow up as they moved to other places. Amongst asymptomatically infected persons, disease transformation in 8/77 (10.39%) and sero-conversion in 62/77 (80.52%) cases were noted. Seven (9.09%) remained sero-positive even after three years. Progression to clinical disease among asymptomatic individuals was taking place at any time up to three years after the baseline survey. If there are no VL /PKDL cases for two or more years, it does not mean that the area is free from leishmaniasis as symptomatic VL or PKDL may appear even after three years, if there are such asymptomatic cases. So, asymptomatic infected individuals need much attention for VL elimination programme that has been initiated by three adjoining endemic countries. A total of 79 asymptomatic VL cases were detected from two kala-azar endemic blocks of Malda districts of West Bengal by active mass screening. Follow study of the asymptomatic cases revealed that 10.39% cases transformed into disease and 9.09% cases remained as sero-positive even after three years. So progression to clinical disease among asymptomatic individuals was taking place at any time up to three years after the baseline survey. Therefore, in a given period if there are no cases of VL/PKDL for two or more years, it does not mean that the area is free from leishmaniasis as symptomatic VL or PKDL may appear even after three years, if there are such asymptomatic cases. So, asymptomatic infected individuals need much attention for VL elimination programme that has been initiated by three adjoining endemic countries.
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Affiliation(s)
- Pabitra Saha
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- Department of Zoology, A. P. C. Roy Govt. College, Himachal Bihar, Matigara, Siliguri, West Bengal, India
| | - Swagata Ganguly
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- Department of Microbiology, N. R. S. Medical College & Hospital, Kolkata, West Bengal, India
| | - Moytrey Chatterjee
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Soumendu Bikash Das
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Pratip K. Kundu
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- Malda Medical College, Malda, West Bengal, India
| | - Subhasish K. Guha
- Department of Tropical Medicine, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Tamal K. Ghosh
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- Medinipur Medical College, West Medinipur, West Bengal, India
| | - Dilip K. Bera
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Nandita Basu
- Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Ardhendu K. Maji
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- * E-mail:
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Das VNR, Pandey RN, Siddiqui NA, Chapman LAC, Kumar V, Pandey K, Matlashewski G, Das P. Longitudinal Study of Transmission in Households with Visceral Leishmaniasis, Asymptomatic Infections and PKDL in Highly Endemic Villages in Bihar, India. PLoS Negl Trop Dis 2016; 10:e0005196. [PMID: 27974858 PMCID: PMC5156552 DOI: 10.1371/journal.pntd.0005196] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 11/17/2016] [Indexed: 12/13/2022] Open
Abstract
Background Visceral Leishmaniasis (VL) is a neglected tropical disease that afflicts some of the poorest populations in the world including people living in the Bihar state of India. Due to efforts from local governments, NGOs and international organizations, the number of VL cases has declined in recent years. Despite this progress, the reservoir for transmission remains to be clearly defined since it is unknown what role post kala-azar dermal leishmaniasis (PKDL) and asymptomatic infections play in transmission. This information is vital to establish effective surveillance and monitoring to sustainably eliminate VL. Methodology/Principal Findings We performed a longitudinal study over a 24-month period to examine VL transmission and seroconversion in households with VL, PKDL and asymptomatic infections in the Saran and Muzaffarpur districts of Bihar. During the initial screening of 5,144 people in 16 highly endemic villages, 195 cases of recently treated VL, 116 healthy rK39 positive cases and 31 PKDL cases were identified. Approximately half of the rK39-positive healthy cases identified during the initial 6-month screening period were from households (HHs) where a VL case had been identified. During the 18-month follow-up period, seroconversion of family members in the HHs with VL cases, PKDL cases, and rK39-positive individuals was similar to control HHs. Therefore, seroconversion was highest in HHs closest to the time of VL disease of a household member and there was no evidence of higher transmission in households with PKDL or healthy rK39-positive HHs. Moreover, within the PKDL HHs, (the initial 31 PKDL cases plus an additional 66 PKDL cases), there were no cases of VL identified during the initial screen or the 18-month follow-up. Notably, 23% of the PKDL cases had no prior history of VL suggesting that infection resulting directly in PKDL is more common than previously estimated. Conclusions/Significance These observations argue that acute VL cases represent the major reservoir for transmission in these villages and early identification and treatment of VL cases should remain a priority for VL elimination. We were unable to obtain evidence that transmission occurs in HHs with a PKDL case. Visceral leishmaniasis (also known as kala-azar) caused by infection with L. donovani is a deadly parasitic disease that afflicts some of world’s poorest populations, including the people of the northern Bihar State of India. Once transmitted to a human by an infected sandfly, the L. donovani parasite migrates from the site of the sandfly bite throughout the reticuloendothelial system, resulting in high levels of infection in the spleen, liver and bone marrow that eventually lead to organ failure and death if not treated effectively. India, Nepal and Bangladesh are currently engaged in a program to eliminate visceral leishmaniasis, principally through early case detection, treatment and vector control. As humans are the only reservoir for L. donovani, it is necessary to understand how the disease is transmitted and specifically what role acute visceral leishmaniasis (VL) cases, asymptomatic infections and post kala-azar dermal leishmaniasis (PKDL) cases play in transmission. We therefore performed a study to determine seroconversion for antibodies against the L. donovani rK39 antigen as a surrogate for transmission in households with VL cases, asymptomatic infections and PKDL cases in 16 highly endemic villages over a 2-year period in Bihar, India. We observed that most transmission occurred in the VL households and further that it occurred closest to the time of acute disease. We were unable to confirm that transmission occurred in the households with either asymptomatic infections or PKDL cases. These observations argue that active surveillance to diagnose and treat VL cases as soon as possible to reduce transmission should remain a priority for VL elimination.
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Affiliation(s)
- Vidya Nand Ravi Das
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | | | | | | | - Vijay Kumar
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Krishna Pandey
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Greg Matlashewski
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
- * E-mail: (PD); (GM)
| | - Pradeep Das
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
- * E-mail: (PD); (GM)
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Use of Recombinant Antigens for Sensitive Serodiagnosis of American Tegumentary Leishmaniasis Caused by Different Leishmania Species. J Clin Microbiol 2016; 55:495-503. [PMID: 27927927 PMCID: PMC5277519 DOI: 10.1128/jcm.01904-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/09/2016] [Indexed: 11/20/2022] Open
Abstract
American tegumentary leishmaniasis (ATL) (also known as cutaneous leishmaniasis [CL]) is caused by various species of protozoa of the genus Leishmania. The diagnosis is achieved on a clinical, epidemiological, and pathological basis, supported by positive parasitological exams and demonstration of leishmanin delayed-type hypersensitivity. Serological assays are not routinely used in the diagnosis because many are considered to have low sensitivity and the particular Leishmania species causing the disease can lead to variable performance. In the present study, we generated recombinant versions of two highly conserved Leishmania proteins, Leishmania (Viannia) braziliensis-derived Lb8E and Lb6H, and evaluated both in enzyme-linked immunosorbent assays (ELISA). Recombinant Lb6H (rLb6H) had better performance and reacted with 100.0% of the ATL and 89.4% of the VL samples. These reactions with rLb6H were highly specific (98.5%) when compared against those for samples from healthy control individuals. We then assessed rLb6H against sera from ATL patients infected with different species of Leishmania prevalent in Brazil [Leishmania (Leishmania) amazonensis, L. (Viannia) braziliensis, and L. (V.) guyanensis] and samples from patients with other infectious diseases. In analyses of 500 sera, ELISA using rLb6H detected all 219 ATL samples (sensitivity of 100.0%) with an overall specificity of 93.9% (considering healthy individuals and other infectious diseases patients). Only a minority of samples from Chagas disease patients possessed antibodies against rLb6H, and all of these responses were low (with a highest reactivity index of 2.2). Taken together, our data support further evaluation of rLb6H and the potential for its routine use in the serological diagnosis of ATL.
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Rock KS, Quinnell RJ, Medley GF, Courtenay O. Progress in the Mathematical Modelling of Visceral Leishmaniasis. ADVANCES IN PARASITOLOGY 2016; 94:49-131. [PMID: 27756459 DOI: 10.1016/bs.apar.2016.08.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The leishmaniases comprise a complex of diseases characterized by clinical outcomes that range from self-limiting to chronic, and disfiguring and stigmatizing to life threatening. Diagnostic methods, treatments, and vector and reservoir control options exist, but deciding the most effective interventions requires a quantitative understanding of the population level infection and disease dynamics. The effectiveness of any set of interventions has to be determined within the context of operational conditions, including economic and political commitment. Mathematical models are the best available tools for studying quantitative systems crossing disciplinary spheres (biology, medicine, economics) within environmental and societal constraints. In 2005, the World Health Assembly and government health ministers of India, Nepal, and Bangladesh signed a Memorandum of Understanding to eliminate the life threatening form of leishmaniasis, visceral leishmaniasis (VL), on the Indian subcontinent by 2015 through a combination of early case detection, improved treatments, and vector control. The elimination target is <1 case/10,000 population at the district or subdistrict level compared to the current 20/10,000 in the regions of highest transmission. Towards this goal, this chapter focuses on mathematical models of VL, and the biology driving those models, to enable realistic predictions of the best combination of interventions. Several key issues will be discussed which have affected previous modelling of VL and the direction future modelling may take. Current understanding of the natural history of disease, immunity (and loss of immunity), and stages of infection and their durations are considered particularly for humans, and also for dogs. Asymptomatic and clinical infection are discussed in the context of their relative roles in Leishmania transmission, as well as key components of the parasite-sandfly-vector interaction and intervention strategies including diagnosis, treatment and vector control. Gaps in current biological knowledge and potential avenues to improve model structures and mathematical predictions are identified. Underpinning the marriage between biology and mathematical modelling, the content of this chapter represents the first step towards developing the next generation of models for VL.
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Affiliation(s)
- K S Rock
- University of Warwick, Coventry, United Kingdom
| | | | - G F Medley
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - O Courtenay
- University of Warwick, Coventry, United Kingdom
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Elimination of visceral leishmaniasis on the Indian subcontinent. THE LANCET. INFECTIOUS DISEASES 2016; 16:e304-e309. [PMID: 27692643 DOI: 10.1016/s1473-3099(16)30140-2] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 04/26/2016] [Accepted: 05/25/2016] [Indexed: 01/08/2023]
Abstract
Visceral leishmaniasis is a serious public health problem on the Indian subcontinent, causing high morbidity and mortality. The governments in the region launched a visceral leishmaniasis elimination initiative in 2005. We review knowledge gaps and research priorities. Key challenges include low coverage of health services for those most at risk, drug resistance, the absence of a vaccine, and the complex biology of the sandfly-human host transmission cycle. Vector control is an essential component, but innovation in this field is insufficient. Substantial progress has been made in the area of diagnostic, therapeutic, and vaccine development, but there are still many hurdles to overcome. For visceral leishmaniasis elimination to become a reality, effective deployment of these existing and new tools is essential. A strong commitment at community level is imperative, and appropriate diagnostic and treatment services as well as effective epidemiological surveillance need to be ensured.
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Lopes CS, Daifalla N, Das B, Dias da Silva V, Campos-Neto A. CD271+ Mesenchymal Stem Cells as a Possible Infectious Niche for Leishmania infantum. PLoS One 2016; 11:e0162927. [PMID: 27622907 PMCID: PMC5021359 DOI: 10.1371/journal.pone.0162927] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 08/28/2016] [Indexed: 12/18/2022] Open
Abstract
Visceral leishmaniasis (VL) is a serious and fatal disease. Therapeutic drugs are toxic and non-sterilizing. The etiological agents Leishmania infantum and Leishmania donovani cause active and asymptomatic diseases. Effective drugs to treat VL exist but unfortunately, post-treatment relapses are common. Little is known why drugs are non-sterilizing or how these intracellular pathogens can escape treatment. Here, using a murine model of VL we found that CD271+/Sca1+ bone marrow mesenchymal stem cells (BM-MSCs) are readily infected in vitro and in vivo by L. infantum. Because BM-MSCs express potent drug efflux pumps, e.g., ABCG2 it is possible that this unique intracellular infectious niche could allow L. infantum to escape anti-parasite drugs.
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Affiliation(s)
- Carolina S. Lopes
- The Forsyth Institute, Cambridge Massachusetts, United States of America
- Department of Biochemistry, Pharmacology, Physiology and Molecular Biology, Institute for Biological and Natural Sciences, Triângulo Mineiro Federal University, Uberaba, MG, Brazil
| | - Nada Daifalla
- The Forsyth Institute, Cambridge Massachusetts, United States of America
| | - Bikul Das
- The Forsyth Institute, Cambridge Massachusetts, United States of America
| | - Valdo Dias da Silva
- Department of Biochemistry, Pharmacology, Physiology and Molecular Biology, Institute for Biological and Natural Sciences, Triângulo Mineiro Federal University, Uberaba, MG, Brazil
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Transmission Dynamics of Visceral Leishmaniasis in the Indian Subcontinent - A Systematic Literature Review. PLoS Negl Trop Dis 2016; 10:e0004896. [PMID: 27490264 PMCID: PMC4973965 DOI: 10.1371/journal.pntd.0004896] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/12/2016] [Indexed: 12/24/2022] Open
Abstract
Background As Bangladesh, India and Nepal progress towards visceral leishmaniasis (VL) elimination, it is important to understand the role of asymptomatic Leishmania infection (ALI), VL treatment relapse and post kala-azar dermal leishmaniasis (PKDL) in transmission. Methodology/ Principal Finding We reviewed evidence systematically on ALI, relapse and PKDL. We searched multiple databases to include studies on burden, risk factors, biomarkers, natural history, and infectiveness of ALI, PKDL and relapse. After screening 292 papers, 98 were included covering the years 1942 through 2016. ALI, PKDL and relapse studies lacked a reference standard and appropriate biomarker. The prevalence of ALI was 4–17-fold that of VL. The risk of ALI was higher in VL case contacts. Most infections remained asymptomatic or resolved spontaneously. The proportion of ALI that progressed to VL disease within a year was 1.5–23%, and was higher amongst those with high antibody titres. The natural history of PKDL showed variability; 3.8–28.6% had no past history of VL treatment. The infectiveness of PKDL was 32–53%. The risk of VL relapse was higher with HIV co-infection. Modelling studies predicted a range of scenarios. One model predicted VL elimination was unlikely in the long term with early diagnosis. Another model estimated that ALI contributed to 82% of the overall transmission, VL to 10% and PKDL to 8%. Another model predicted that VL cases were the main driver for transmission. Different models predicted VL elimination if the sandfly density was reduced by 67% by killing the sandfly or by 79% by reducing their breeding sites, or with 4–6y of optimal IRS or 10y of sub-optimal IRS and only in low endemic setting. Conclusion/ Significance There is a need for xenodiagnostic and longitudinal studies to understand the potential of ALI and PKDL as reservoirs of infection. The role of asymptomatic Leishmania infection (ALI), PKDL and VL relapse in transmission is unclear as VL elimination is achieved in the Indian subcontinent. ALI, PKDL and relapse studies lacked a reference standard and appropriate biomarker. ALI was 4–17-fold more prevalent than VL. The risk of ALI was higher in VL case contacts. Most infections remained asymptomatic or resolved spontaneously. The natural history of PKDL showed variability. Twenty nine percent had no past history of VL treatment. The risk of VL relapse was higher with HIV co-infection. Modelling studies predicted different effects. Early diagnosis was unlikely to eliminate VL in the long term. ALI was predicted to contribute to 82% of the overall transmission, VL to 10% and PKDL to 8%. Another model predicted that VL cases were the main driver for transmission. VL elimination was predicted if the sandfly density was reduced by 67% by killing the sandfly or by 79% by reducing their breeding sites, or with 4–6y of optimal IRS or 10y of sub-optimal IRS and only in low endemic setting. There is a need for more studies to fully understand the potential of ALI and PKDL as reservoirs of infection.
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Accurate Serodetection of Asymptomatic Leishmania donovani Infection by Use of Defined Antigens. J Clin Microbiol 2016; 54:1025-30. [PMID: 26842701 PMCID: PMC4809943 DOI: 10.1128/jcm.02620-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/08/2016] [Indexed: 12/16/2022] Open
Abstract
Infection with Leishmania donovani is typically asymptomatic, but a significant number of individuals may progress to visceral leishmaniasis (VL), a deadly disease that threatens 200 million people in areas where it is endemic. While diagnosis of acute VL has been simplified by the use of cost-effective confirmatory serological tests, similar standardized tools are not widely available for detecting asymptomatic infection, which can be 4 to 20 times more prevalent than active disease. A simple and accurate serological test that is capable of detecting asymptomatic L. donovani infection will be useful for surveillance programs targeting VL control and elimination. To address this unmet need, we evaluated recombinant antigens for their ability to detect serum antibodies in 104 asymptomatic L. donovani-infected individuals (qualified as positive for L. donovani-specific antibodies by direct agglutination test [DAT]) from the Mymensingh district of Bangladesh where VL is hyperendemic. The novel proteins rKR95 and rTR18 possessed the greatest potential and detected 69% of DAT-positive individuals, with rKR95 being more robust in reactivity. Agreement in results for individuals with high DAT responses, who are more likely to progress to VL disease, was 74%. When considered along with rK39, a gold standard antigen that is used to confirm clinical diagnosis of VL but that is now becoming widely used for surveillance, rKR95 and rTR18 conferred a sensitivity of 84% based on a theoretical combined estimate. Our data indicate that incorporating rKR95 and rTR18 with rK39 in serological tests amenable to rapid or high-throughput screening may enable simple and accurate detection of asymptomatic infection. Such tests will be important tools to measure L. donovani infection rates, a primary goal in surveillance and a critical measurement with which to assess elimination programs.
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Developments in Diagnosis of Visceral Leishmaniasis in the Elimination Era. J Parasitol Res 2015; 2015:239469. [PMID: 26843964 PMCID: PMC4710934 DOI: 10.1155/2015/239469] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 12/06/2015] [Accepted: 12/14/2015] [Indexed: 11/29/2022] Open
Abstract
Visceral leishmaniasis (VL) is the most devastating parasitic infection worldwide causing high morbidity and mortality. Clinical presentation of VL ranges from asymptomatic or subclinical infection to severe and complicated symptomatic disease. A major challenge in the clinical management of VL is the weakness of health systems in disease endemic regions. People affected by VL mostly present to primary health care centers (PHCs), often late in their therapeutic itinerary. PHC physicians face a major challenge: they do not deal with a single disease issue but with patients presenting with complaints pointing to several diagnostic possibilities. Risk exists when some patients having less clinical manifestations are misdiagnosed. Therefore, field based accurate, sensitive, and cost effective rapid diagnostic tools that can detect disease in its mildest form are essential for effective control and reaching the goal of VL elimination. In this review, we discuss the current status and challenges of various diagnostic tools for the diagnosis of VL and assess their application in resource poor settings.
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Chapman LAC, Dyson L, Courtenay O, Chowdhury R, Bern C, Medley GF, Hollingsworth TD. Quantification of the natural history of visceral leishmaniasis and consequences for control. Parasit Vectors 2015; 8:521. [PMID: 26490668 PMCID: PMC4618734 DOI: 10.1186/s13071-015-1136-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/03/2015] [Indexed: 01/20/2023] Open
Abstract
Background Visceral leishmaniasis has been targeted for elimination as a public health problem (less than 1 case per 10,000 people per year) in the Indian sub-continent by 2017. However, there is still a high degree of uncertainty about the natural history of the disease, in particular about the duration of asymptomatic infection and the proportion of asymptomatically infected individuals that develop clinical visceral leishmaniasis. Quantifying these aspects of the disease is key for guiding efforts to eliminate visceral leishmaniasis and maintaining elimination once it is reached. Methods Data from a detailed epidemiological study in Bangladesh in 2002–2004 was analysed to estimate key epidemiological parameters. The role of diagnostics in determining the probability and rate of progression to clinical disease was estimated by fitting Cox proportional hazards models. A multi-state Markov model of the natural history of visceral leishmaniasis was fitted to the data to estimate the asymptomatic infection period and the proportion of asymptomatic individuals going on to develop clinical symptoms. Results At the time of the study, individuals were taking several months to be diagnosed with visceral leishmaniasis, leading to many opportunities for ongoing transmission. The probability of progression to clinical disease was strongly associated with initial seropositivity and even more strongly with seroconversion, with most clinical symptoms developing within a year. The estimated average durations of asymptomatic infection and symptomatic infection for our model of the natural history are 147 days (95 % CI 130–166) and 140 days (95 % CI 123–160), respectively, and are significantly longer than previously reported estimates. We estimate from the data that 14.7 % (95 % CI 12.6-20.0 %) of asymptomatic individuals develop clinical symptoms—a greater proportion than previously estimated. Conclusions Extended periods of asymptomatic infection could be important for visceral leishmaniasis transmission, but this depends critically on the relative infectivity of asymptomatic and symptomatic individuals to sandflies. These estimates could be informed by similar analysis of other datasets. Our results highlight the importance of reducing times from onset of symptoms to diagnosis and treatment to reduce opportunities for transmission. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1136-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lloyd A C Chapman
- School of Life Sciences, University of Warwick, Gibbet Hill Campus, Coventry, CV4 7AL, UK.
| | - Louise Dyson
- School of Life Sciences, University of Warwick, Gibbet Hill Campus, Coventry, CV4 7AL, UK
| | - Orin Courtenay
- School of Life Sciences, University of Warwick, Gibbet Hill Campus, Coventry, CV4 7AL, UK
| | - Rajib Chowdhury
- Country Programme Manager - Bangladesh, KalaCORE Programme, Dhaka, Bangladesh.,Department of Medical Entomology, National Institute of Preventive and Social Medicine (NIPSOM), Mohakhali, Dhaka, Bangladesh
| | - Caryn Bern
- UCSF School of Medicine, 550 16th Street, San Francisco, CA, 94158, USA
| | - Graham F Medley
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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Engwerda CR, Matlashewski G. Development of Leishmania vaccines in the era of visceral leishmaniasis elimination. Trans R Soc Trop Med Hyg 2015; 109:423-4. [DOI: 10.1093/trstmh/trv039] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 04/29/2015] [Indexed: 11/15/2022] Open
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IL10 Variant g.5311A Is Associated with Visceral Leishmaniasis in Indian Population. PLoS One 2015; 10:e0124559. [PMID: 25941808 PMCID: PMC4420251 DOI: 10.1371/journal.pone.0124559] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 03/16/2015] [Indexed: 12/20/2022] Open
Abstract
Background Visceral leishmaniasis (VL) is a multifactorial disease, where the host genetics play a significant role in determining the disease outcome. The immunological role of anti-inflammatory cytokine, Interleukin 10 (IL10), has been well-documented in parasite infections and considered as a key regulatory cytokine for VL. Although VL patients in India display high level of IL10 in blood serum, no genetic study has been conducted to assess the VL susceptibility / resistance. Therefore, the aim of this study is to investigate the role of IL10 variations in Indian VL; and to estimate the distribution of disease associated allele in diverse Indian populations. Methodology All the exons and exon-intron boundaries of IL10 were sequenced in 184 VL patients along with 172 ethnically matched controls from VL endemic region of India. Result and Discussion Our analysis revealed four variations; rs1518111 (2195 A>G, intron), rs1554286 (2607 C>T, intron), rs3024496 (4976 T>C, 3’ UTR) and rs3024498 (5311 A>G, 3’ UTR). Of these, a variant g.5311A is significantly associated with VL (χ2=18.87; p =0.00001). In silico approaches have shown that a putative micro RNA binding site (miR-4321) is lost in rs3024498 mRNA. Further, analysis of the above four variations in 1138 individuals from 34 ethnic populations, representing different social and linguistic groups who are inhabited in different geographical regions of India, showed variable frequency. Interestingly, we have found, majority of the tribal populations have low frequency of VL (‘A’ of rs3024498); and high frequency of leprosy (‘T’ of rs1554286), and Behcet’s (‘A’ of rs1518111) associated alleles, whereas these were vice versa in castes. Our findings suggest that majority of tribal populations of India carry the protected / less severe allele against VL, while risk / more severe allele for leprosy and Behcet’s disease. This study has potential implications in counseling and management of VL and other infectious diseases.
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Arora S, Bal AS, Baveja S, Sood A, Rathi KR, Patil P. Atypical post kala azar dermal leishmaniasis with "muzzle area" swelling. Indian J Dermatol 2015; 60:88-90. [PMID: 25657406 PMCID: PMC4318072 DOI: 10.4103/0019-5154.147809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
A 50-year-old male presented with recurrent swelling of the muzzle area of the face with history of low-grade intermittent fever of 3 year duration managed variously with antibiotics, systemic steroids, and antituberculous therapy. Skin biopsy revealed a granulomatous infiltration negative for acid-fast bacilli and leishmania donovan bodies. Immunochromatography test for rK 39 antigen and polymerase chain reaction for leishmania was positive. He was diagnosed as a case of post kala azar dermal leishmaniasis, managed with injection sodium stibogluconate and followed-up thereafter.
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Affiliation(s)
- Sandeep Arora
- Department of Skin, Army College of Medical Sciences and Base Hospital, Cantt, New Delhi, India
| | - Arvinder Singh Bal
- Department of Skin, Army College of Medical Sciences and Base Hospital, Cantt, New Delhi, India
| | - Sukriti Baveja
- Department of Skin, Army College of Medical Sciences and Base Hospital, Cantt, New Delhi, India
| | - Aradhana Sood
- Department of Skin, Army College of Medical Sciences and Base Hospital, Cantt, New Delhi, India
| | - Khushi Ram Rathi
- Department of Pathology, Army College of Medical Sciences and Base Hospital, Cantt, New Delhi, India
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Sudarshan M, Singh T, Singh AK, Chourasia A, Singh B, Wilson ME, Chakravarty J, Sundar S. Quantitative PCR in epidemiology for early detection of visceral leishmaniasis cases in India. PLoS Negl Trop Dis 2014; 8:e3366. [PMID: 25503103 PMCID: PMC4263468 DOI: 10.1371/journal.pntd.0003366] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 10/23/2014] [Indexed: 12/04/2022] Open
Abstract
Introduction Studies employing serological, DTH or conventional PCR techniques suggest a vast proportion of Leishmania infected individuals living in regions endemic for Visceral Leishmaniasis (VL) remain asymptomatic. This study was designed to assess whether quantitative PCR (qPCR) can be used for detection of asymptomatic or early Leishmania donovani infection and as a predictor of progression to symptomatic disease. Methods The study included 1469 healthy individuals living in endemic region (EHC) including both serology-positive and -negative subjects. TaqMan based qPCR assay was done on peripheral blood of each subject using kDNA specific primers and probes. Results A large proportion of EHC 511/1469 (34.78%) showed qPCR positivity and 56 (3.81% of 1469 subjects) had more than 1 calculated parasite genome/ml of blood. However, the number of individuals with parasite load above 5 genomes/ml was only 20 (1.36% of 1469). There was poor agreement between serological testing and qPCR (k = 0.1303), and 42.89% and 31.83% EHC were qPCR positive in seropositive and seronegative groups, respectively. Ten subjects had developed to symptomatic VL after 12 month of their follow up examination, of which eight were initially positive according to qPCR and among these, five had high parasite load. Discussion Thus, qPCR can help us to detect significant early parasitaemia, thereby assisting us in recognition of potential progressors to clinical disease. This test could facilitate early intervention, decreased morbidity and mortality, and possibly interruption of disease transmission. Anthroponotic VL caused by Leishmania donovani in the Indian subcontinent accounts for 70% of the world burden of VL. Among the estimated 100,000 cases of VL acquired annually in India, 90% occur in the state of Bihar. Leishmania infection can result in either symptomatic or asymptomatic infection. L. donovani infection can also manifest as post-kala azar dermal leishmaniasis, a chronic cutaneous form thought to provide the reservoir for anthroponotic transmission of VL in regions endemic for this parasite species. We hypothesized that, in areas endemic for L. donovani, asymptomatic infections might also play a crucial role in disease transmission. This study describes use of quantitative PCR (qPCR) to determine the infection status in individuals living in an endemic region of India. We hypothesized that parasite load estimation by qPCR of peripheral blood cells among healthy individuals living in the endemic region might reveal the true frequency of infections through direct evidence of parasitemia. We reasoned this test would detect both asymptomatic non-progressors as well as asymptomatic individuals who will progress to fully symptomatic VL. Serologic testing by ELISA or DAT showed poor agreement with molecular detection of parasite DNA by qPCR, suggesting the tests differentiate between infection and immune response. Amongst ten healthy individuals who progressed to VL, only six were serologically positive whereas eight were initially qPCR positive, among whom five had high parasite loads in their blood. Thus, deployment of qPCR technique to estimate the presence and level of parasitemia in healthy individuals from Leishmania endemic regions may contribute to early case detection, thereby reducing morbidity and mortality. Consistent with the goals of the VL control and elimination program, this early intervention approach could help interrupt disease transmission.
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Affiliation(s)
- Medhavi Sudarshan
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Toolika Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Abhishek Kumar Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Ankita Chourasia
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Bhawana Singh
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Mary E Wilson
- Departments of Internal Medicine and Microbiology, University of Iowa and the VA Medical Center, Iowa City, Iowa, United States of America
| | - Jaya Chakravarty
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Bhattacharyya T, Ayandeh A, Falconar AK, Sundar S, El-Safi S, Gripenberg MA, Bowes DE, Thunissen C, Singh OP, Kumar R, Ahmed O, Eisa O, Saad A, Silva Pereira S, Boelaert M, Mertens P, Miles MA. IgG1 as a potential biomarker of post-chemotherapeutic relapse in visceral leishmaniasis, and adaptation to a rapid diagnostic test. PLoS Negl Trop Dis 2014; 8:e3273. [PMID: 25340782 PMCID: PMC4207679 DOI: 10.1371/journal.pntd.0003273] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 09/14/2014] [Indexed: 12/02/2022] Open
Abstract
Background Visceral leishmaniasis (VL), caused by protozoa of the Leishmania donovani complex, is a widespread parasitic disease of great public health importance; without effective chemotherapy symptomatic VL is usually fatal. Distinction of asymptomatic carriage from progressive disease and the prediction of relapse following treatment are hampered by the lack of prognostic biomarkers for use at point of care. Methodology/Principal Findings All IgG subclass and IgG isotype antibody levels were determined using unpaired serum samples from Indian and Sudanese patients with differing clinical status of VL, which included pre-treatment active VL, post-treatment cured, post-treatment relapsed, and post kala-azar dermal leishmaniasis (PKDL), as well as seropositive (DAT and/or rK39) endemic healthy controls (EHCs) and seronegative EHCs. L. donovani antigen-specific IgG1 levels were significantly elevated in relapsed versus cured VL patients (p<0.0001). Using paired Indian VL sera, consistent with the known IgG1 half-life, IgG1 levels had not decreased significantly at day 30 after the start of treatment (p = 0.8304), but were dramatically decreased by 6 months compared to day 0 (p = 0.0032) or day 15 (p<0.0001) after start of treatment. Similarly, Sudanese sera taken soon after treatment did not show a significant change in the IgG1 levels (p = 0.3939). Two prototype lateral flow immunochromatographic rapid diagnostic tests (RDTs) were developed to detect IgG1 levels following VL treatment: more than 80% of the relapsed VL patients were IgG1 positive; at least 80% of the cured VL patients were IgG1 negative (p<0.0001). Conclusions/Significance Six months after treatment of active VL, elevated levels of specific IgG1 were associated with treatment failure and relapse, whereas no IgG1 or low levels were detected in cured VL patients. A lateral flow RDT was successfully developed to detect anti-Leishmania IgG1 as a potential biomarker of post-chemotherapeutic relapse. Visceral leishmaniasis (VL) is a systemic disease with highest prevalence in South Asia, East Africa, and Brazil. VL is caused by protozoan (unicellular) parasites of the Leishmania donovani complex, transmitted to humans when an infected sandfly takes a bloodmeal. Within the human host, the parasites replicate within cells, particularly of bone marrow and spleen. Without effective treatment, symptomatic VL is usually fatal. As outlined in a recent World Health Organisation report, the development of new diagnostic tools to test for successful cure after chemotherapy is a research priority. In this work we investigated the association of clinical status of VL patients (active pre-treatment, and those deemed cured or relapsed post-treatment) with subclasses of the IgG antibody response made to L. donovani infection. We show that high levels of subclass IgG1 are found in pre-treatment and relapsed patients, but are very much lower in patients deemed to be cured. We further show that the decrease in IgG1 is detectable in patients 6 months after successful treatment, and that this detection method can be adapted to a rapid diagnostic test format requiring minimal technical expertise. Thus we believe that IgG1 levels are potentially a biomarker of post-chemotherapeutic monitoring.
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Affiliation(s)
- Tapan Bhattacharyya
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Armon Ayandeh
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Andrew K Falconar
- Departamento de Medicina, Universidad del Norte, Barranquilla, Colombia
| | - Shyam Sundar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Sayda El-Safi
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Marissa A Gripenberg
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Duncan E Bowes
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Om Prakash Singh
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Rajiv Kumar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India; Immunology and Infection Laboratory, Queensland Institute of Medical Research, Herston, Queensland, Australia
| | - Osman Ahmed
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan; Department of Laboratory Medicine, Karolinska Insitutet, Stockholm, Sweden
| | - Osama Eisa
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Alfarazdeg Saad
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Sara Silva Pereira
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Marleen Boelaert
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | | | - Michael A Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Mishra A, Jha AN, van Tong H, Singh VK, Gomes CEM, Singh L, Velavan TP, Thangaraj K. Analysis of genetic variants in the IL4 promoter and VNTR loci in Indian patients with Visceral Leishmaniasis. Hum Immunol 2014; 75:1177-81. [PMID: 25454624 DOI: 10.1016/j.humimm.2014.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 06/05/2014] [Accepted: 10/09/2014] [Indexed: 11/17/2022]
Abstract
Visceral Leishmaniasis (VL) is the most severest form of Leishmaniasis and resistance to infection is mediated by cellular immune responses. Interleukin 4 (IL-4) orchestrates of Th2 and Th1 immune responses during infections. In this study, we aimed to investigate possible association between three functional IL-4 polymorphisms -590C/T (rs2243250), -34C/T (rs2070874) and 70bp VNTR (rs79071878 in intron3) with VL in an Indian cohort comprising of 197 VL patients and 193 healthy controls. The three investigated IL-4 polymorphisms were in strong linkage disequilibrium. The investigated IL-4 alleles, genotypes and the reconstructed haplotypes were not significantly distributed between the VL patients and healthy controls. Our study signifies no possible association of functional IL-4 polymorphisms with Indian VL and postulate other vital genes involved in the IL-4 pathway may provide genetic clues to elucidate of IL-4 regulation and immune-pathogenesis during VL.
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Affiliation(s)
- Anshuman Mishra
- CSIR - Center for Cellular and Molecular Biology, Hyderabad, India
| | - Aditya Nath Jha
- CSIR - Center for Cellular and Molecular Biology, Hyderabad, India; Sickle Cell Institute Chattisgarh (SCIC), Raipur, India
| | - Hoang van Tong
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | | | | | - Lalji Singh
- CSIR - Center for Cellular and Molecular Biology, Hyderabad, India; Banaras Hindu University, Varanasi, India; Genome Foundation, Hyderabad, India
| | - Thirumalaisamy P Velavan
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; Fondation Congolaise pour la Recherche Medicale, Brazzaville, People's Republic of Congo.
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Das S, Matlashewski G, Bhunia GS, Kesari S, Das P. Asymptomatic Leishmania infections in northern India: a threat for the elimination programme? Trans R Soc Trop Med Hyg 2014; 108:679-84. [PMID: 25205664 DOI: 10.1093/trstmh/tru146] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Visceral leishmaniasis (VL) continues to embody as a mammoth public health problem and hurdle to the socioeconomic development of Bihar, India. Interestingly, all leishmanial infections do not lead to overt clinical disease and may stay asymptomatic for a period of time. Asymptomatic cases of VL are considered as probable potential reservoirs of VL, and thus can play a major role in transmission of the disease in highly endemic areas of Bihar, India. They outnumber the exact disease burden in endemic areas of this region, thus jeopardizing the goal of the elimination program that is due by 2015. This article discusses the potential risk factors, epidemiological markers of transmission and requirement of highly sensitive diagnostic tools for efficient recognition of the high risk groups of conversion to symptomatic for proper designing of strategies for implementation of the control programs.
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Affiliation(s)
- Sushmita Das
- Department of Microbiology, All-India Institute of Medical Sciences, Phulwarisharif, Patna, Bihar, India
| | - Greg Matlashewski
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Gouri Sankar Bhunia
- Departments of Molecular Parasitology and Vector Biology, Rajendra Memorial Research Institute of Medical Sciences, Indian Council of Medical Research, Agamkuan, Patna, Bihar, India
| | - Sreekanth Kesari
- Departments of Molecular Parasitology and Vector Biology, Rajendra Memorial Research Institute of Medical Sciences, Indian Council of Medical Research, Agamkuan, Patna, Bihar, India
| | - Pradeep Das
- Departments of Molecular Parasitology and Vector Biology, Rajendra Memorial Research Institute of Medical Sciences, Indian Council of Medical Research, Agamkuan, Patna, Bihar, India
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Malaviya P, Picado A, Hasker E, Ostyn B, Kansal S, Singh RP, Shankar R, Boelaert M, Sundar S. Health & Demographic Surveillance System profile: the Muzaffarpur-TMRC Health and Demographic Surveillance System. Int J Epidemiol 2014; 43:1450-7. [PMID: 25186307 DOI: 10.1093/ije/dyu178] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Muzaffarpur-TMRC Health and Demographic Surveillance System (HDSS), established in 2007, was developed as an enlargement of the scope of a research collaboration on the project Visceral Leishmaniasis in Bihar, which had been ongoing since 2005. The HDSS is located in a visceral leishmaniasis (VL)-endemic area in the Muzaffarpur district of Bihar state in India. It is the only HDSS conducting research on VL, which is a vector-borne infectious disease transmitted by female phlebotomine sandflies and is fatal if left untreated. Currently the HDSS serves a population of over 105,000 in 66 villages. The HDSS collects data on vital events including pregnancies, births, deaths, migration and marriages, as well as other socio-economic indicators, at regular intervals. Incident VL cases are identified. The HDSS team is experienced in conducting both qualitative and quantitative studies, sample collection and rapid diagnostic tests in the field. In each village, volunteers connect the HDSS team with the community members. The Muzaffarpur-TMRC HDSS provides opportunities for studies on VL and other neglected tropical diseases (NTDs) and their interaction with demographic events such as migration. Queries related to research collaborations and data sharing can be sent to Dr Shyam Sundar at [drshyamsundar@hotmail.com].
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Affiliation(s)
- Paritosh Malaviya
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Albert Picado
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Epco Hasker
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Bart Ostyn
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Sangeeta Kansal
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Rudra Pratap Singh
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Ravi Shankar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Marleen Boelaert
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Shyam Sundar
- Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Institute of Tropical Medicine, Antwerp, Belgium and Barcelona Centre for International Health Research, Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
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Selvapandiyan A, Dey R, Gannavaram S, Solanki S, Salotra P, Nakhasi HL. Generation of growth arrested Leishmania amastigotes: a tool to develop live attenuated vaccine candidates against visceral leishmaniasis. Vaccine 2014; 32:3895-901. [PMID: 24837513 DOI: 10.1016/j.vaccine.2014.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 04/19/2014] [Accepted: 05/01/2014] [Indexed: 12/24/2022]
Abstract
Visceral leishmaniasis (VL) is fatal if not treated and is prevalent widely in the tropical and sub-tropical regions of world. VL is caused by the protozoan parasite Leishmania donovani or Leishmania infantum. Although several second generation vaccines have been licensed to protect dogs against VL, there are no effective vaccines against human VL [1]. Since people cured of leishmaniasis develop lifelong protection, development of live attenuated Leishmania parasites as vaccines, which can have controlled infection, may be a close surrogate to leishmanization. This can be achieved by deletion of genes involved in the regulation of growth and/or virulence of the parasite. Such mutant parasites generally do not revert to virulence in animal models even under conditions of induced immune suppression due to complete deletion of the essential gene(s). In the Leishmania life cycle, the intracellular amastigote form is the virulent form and causes disease in the mammalian hosts. We developed centrin gene deleted L. donovani parasites that displayed attenuated growth only in the amastigote stage and were found safe and efficacious against virulent challenge in the experimental animal models. Thus, targeting genes differentially expressed in the amastigote stage would potentially attenuate only the amastigote stage and hence controlled infectivity may be effective in developing immunity. This review lays out the strategies for attenuation of the growth of the amastigote form of Leishmania for use as live vaccine against leishmaniasis, with a focus on visceral leishmaniasis.
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Affiliation(s)
| | - Ranadhir Dey
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Bethesda, MD, USA
| | - Sreenivas Gannavaram
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Bethesda, MD, USA
| | - Sumit Solanki
- Institute of Molecular Medicine, New Delhi, India; C.G. Bhakta Institute of Biotechnology, Tarsadi, Gujarat, India
| | - Poonam Salotra
- National Institute of Pathology (ICMR), New Delhi, India
| | - Hira L Nakhasi
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Bethesda, MD, USA
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Singh OP, Hasker E, Sacks D, Boelaert M, Sundar S. Asymptomatic Leishmania infection: a new challenge for Leishmania control. Clin Infect Dis 2014; 58:1424-9. [PMID: 24585564 DOI: 10.1093/cid/ciu102] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Visceral leishmaniasis (VL) is a serious parasitic disease, causing high morbidity and mortality in the developing world. The pathogenesis of VL is complex, and the clinical presentation ranges from asymptomatic infection to severe and fatal disease. Despite a wealth of research on the full-blown "clinical VL" syndrome, asymptomatic leishmania infections remain poorly understood. Asymptomatic infection could present a major challenge for control programs if its infectiousness is confirmed. In this viewpoint, we highlight the crucial knowledge gaps as well as the obstacles in research on asymptomatic leishmanial infection. Research in this area is essential for the development of more-effective VL control strategies.
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Affiliation(s)
- Om Prakash Singh
- Infectious Disease Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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45
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Strong association between serological status and probability of progression to clinical visceral leishmaniasis in prospective cohort studies in India and Nepal. PLoS Negl Trop Dis 2014; 8:e2657. [PMID: 24466361 PMCID: PMC3900391 DOI: 10.1371/journal.pntd.0002657] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 12/05/2013] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Asymptomatic persons infected with the parasites causing visceral leishmaniasis (VL) usually outnumber clinically apparent cases by a ratio of 4-10 to 1. We assessed the risk of progression from infection to disease as a function of DAT and rK39 serological titers. METHODS We used available data on four cohorts from villages in India and Nepal that are highly endemic for Leishmania donovani. In each cohort two serosurveys had been conducted. Based on results of initial surveys, subjects were classified as seronegative, moderately seropositive or strongly seropositive using both DAT and rK39. Based on the combination of first and second survey results we identified seroconvertors for both markers. Seroconvertors were subdivided in high and low titer convertors. Subjects were followed up for at least one year following the second survey. Incident VL cases were recorded and verified. RESULTS We assessed a total of 32,529 enrolled subjects, for a total follow-up time of 72,169 person years. Altogether 235 incident VL cases were documented. The probability of progression to disease was strongly associated with initial serostatus and with seroconversion; this was particularly the case for those with high titers and most prominently among seroconvertors. For high titer DAT convertors the hazard ratio reached as high as 97.4 when compared to non-convertors. The strengths of the associations varied between cohorts and between markers but similar trends were observed between the four cohorts and the two markers. DISCUSSION There is a strongly increased risk of progressing to disease among DAT and/or rK39 seropositives with high titers. The options for prophylactic treatment for this group merit further investigation, as it could be of clinical benefit if it prevents progression to disease. Prophylactic treatment might also have a public health benefit if it can be corroborated that these asymptomatically infected individuals are infectious for sand flies.
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Sarkari B, Gadami F, Shafiei R, Motazedian MH, Sedaghat F, Kasraian L, Tavasoli AR, Zarnegar G, Nikmanesh Y, Davami MH. Seroprevalence of Leishmania infection among the healthy blood donors in kala-azar endemic areas of Iran. J Parasit Dis 2013; 39:545-9. [PMID: 26345068 DOI: 10.1007/s12639-013-0393-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/03/2013] [Indexed: 11/30/2022] Open
Abstract
Visceral leishmaniasis (VL) is a serious health problem in Iran. The disease is mainly transmitted by sand fly bites, but its transmission through transfusion in endemic areas may also occur. The current study aimed to determine the prevalence of Leishmania infection among blood donors in VL-endemic areas in south of Iran. A total of 2003 healthy blood donors from blood service centers in five VL-endemic districts in Fars province, southern Iran, were enrolled in the study. The blood samples were assessed for antibodies against Leishmania infantum by direct agglutination test (DAT). Seropositive subjects were tested for the presence of L. infantum DNA in their buffy coat by the molecular method. Socio-demographic features of the subjects were also documented during sample collecting. The mean age of participants was 36.3 (SD = 10.7 years). Male constituted 94.7 % of the subjects while only 5.3 % of donors were female. Twenty-eight blood donors (1.4 %) were positive for Leishmania infection by DAT. Only one of these seropositive donors was positive for Leishmania infection by polymerase chain reaction. A significant correlation was found between age, the place of residence and seropositivity to Leishmania (P < 0.05). Findings of this study revealed that the prevalence of Leishmania infection among blood donors in transfusion centers in the VL-endemic areas in Iran is relatively high. These asymptomatic blood donors may constitute a risk of transmitting of VL to susceptible recipients.
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Affiliation(s)
- B Sarkari
- Basic Sciences in Infectious Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - F Gadami
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - R Shafiei
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M H Motazedian
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - F Sedaghat
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - L Kasraian
- Education Unit, Shiraz Blood Transfusion Organization, Shiraz, Iran
| | - A R Tavasoli
- Education Unit, Shiraz Blood Transfusion Organization, Shiraz, Iran
| | - G Zarnegar
- Education Unit, Shiraz Blood Transfusion Organization, Shiraz, Iran
| | - Y Nikmanesh
- Education Unit, Shiraz Blood Transfusion Organization, Shiraz, Iran
| | - M H Davami
- Department of Parasitology and Mycology, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran
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