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Khogali A, Elnaiem DEA, Díaz-Regañón R, Jibreel T, Nour BYM, Abdelrahman SH, Molina R, Jiménez M. Infection of Leishmania donovani in Phlebotomus orientalis Sand Flies at Different Microhabitats of a Kala-Azar Endemic Village in Eastern Sudan. Trop Med Infect Dis 2024; 9:40. [PMID: 38393129 PMCID: PMC10892308 DOI: 10.3390/tropicalmed9020040] [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: 12/21/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/25/2024] Open
Abstract
A study was carried out to compare the infection rates of Leishmania donovani in Phlebotomus orientalis sandflies at different microhabitats of a VL endemic village in Gedarif state, Sudan. DNA extracts of 1078 P. orientalis sand fly females sampled by CDC light traps from indoor, outdoor, peri-domestic, and sylvatic sites, in three transmission seasons, March-June 2016-18, in Helat-Belo village, were subjected to independent PCR amplifications targeting Leishmania kDNA and the cpb gene followed by ITS1 region sequencing. Leishmania kDNA was detected in 1.4% of the 1078 P. orientalis females captured in the area. Two of these specimens showed a characteristic 741 bp band of L. donovani after cpb gene amplification. The DNA sequence of the ITS1 region of the parasites matched the ITS1 L. donovani genotype F. There were no signficant differences between rates of infection of L. donovani in P. orientalis captured at different sites. Blood meals found in infected flies origninated from human (5 specimens), cattle (4 specimens) and donkey (2 specimens). The finding of fresh cow and donkey blood in the infected flies suggests the possible role of these animals in the zoopotentiation and/or zooprophylaxis against VL. The study provides important information for VL transmission models and control programs in East Africa.
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Affiliation(s)
- Altayeb Khogali
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani 21111, Sudan; (A.K.); (T.J.); (B.Y.M.N.); (S.H.A.)
| | - Dia-Eldin A. Elnaiem
- Department of Natural Sciences, University of Maryland Eastern Shore, 1 Backbone Rd., Princess Anne, MD 21853, USA
| | - Ramón Díaz-Regañón
- Medical Entomology Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain; (R.D.-R.); (R.M.)
| | - Tayseer Jibreel
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani 21111, Sudan; (A.K.); (T.J.); (B.Y.M.N.); (S.H.A.)
| | - Bakri Y. M. Nour
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani 21111, Sudan; (A.K.); (T.J.); (B.Y.M.N.); (S.H.A.)
| | - Samira Hamid Abdelrahman
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani 21111, Sudan; (A.K.); (T.J.); (B.Y.M.N.); (S.H.A.)
| | - Ricardo Molina
- Medical Entomology Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain; (R.D.-R.); (R.M.)
- Collaborative Biomedical Research Center in Infectious Diseases (CIBERINFEC), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Maribel Jiménez
- Medical Entomology Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain; (R.D.-R.); (R.M.)
- Collaborative Biomedical Research Center in Infectious Diseases (CIBERINFEC), Instituto de Salud Carlos III, 28029 Madrid, Spain
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Jibreel T, Khogali A, Jiménez M, Raiyed A, Dakein O, Alsharif B, Khalid NM, Osman OF, Nour BYM, Mohamed GH, Molina R, Vidal-López A, Díaz-Regañón R, den Boer M, Alvar J, Courtenay O, Elnaiem DE. Host preference and human blood index of Phlebotomus orientalis, an exophilic sand fly vector of visceral leishmaniasis in eastern Sudan. MEDICAL AND VETERINARY ENTOMOLOGY 2023; 37:782-792. [PMID: 37540228 DOI: 10.1111/mve.12683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 07/10/2023] [Indexed: 08/05/2023]
Abstract
Visceral leishmaniasis (VL, kala azar), caused by Leishmania donovani, transmitted by Phlebotomus orientalis, is a serious systemic disease that causes high morbidity and mortality rates in Sudan and other parts of East Africa and the world. Despite progress in understanding the epidemiology of the disease in East Africa, little is known about the host preference of P. orientalis in kala azar endemic villages of Sudan, which have some of the highest VL incidence rates in the world. The present study used host choice experiments and blood-meal identification approaches to determine the host preference of P. orientalis in kala azar endemic villages in Gedarif state, eastern Sudan. In the host choice experiment, tent traps were used to compare the attractiveness of cows, donkeys, sheep and goats for host-seeking P. orientalis. In the blood-meal identification study, blood-fed P. orientalis females, captured inside houses and peri-domestic habitats, were subjected to molecular typing using cytochrome b gene (cyt b) amplification and sequence analysis. Cows and donkeys were the most attractive to blood-seeking P. orientalis, followed by goats. Similarly, the blood-meal analysis of P. orientalis showed that the vector preferentially feeds on cows, followed by donkeys, humans and goats. The human blood index of P. orientalis was 19.4% (42/216), indicating a high zoophilic habit of the vector, both inside and outside the houses. Although the order of host preference varied by location, it was clear that cows are the most preferred host of P. orientalis in the area. Results are discussed in relation to the role of domestic/livestock animals in VL zoopotentiation and zooprophylaxis. Inference is made on the potential impact of insecticide treatment of cows in control of the vector and the transmission of VL in Sudan and other parts of East Africa.
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Affiliation(s)
- Tayseer Jibreel
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani, Sudan
| | - Altayeb Khogali
- Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani, Sudan
| | - Maribel Jiménez
- Laboratorio de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Adeel Raiyed
- Department of Zoology, Faculty of Science, University of Khartoum, Khartoum, Sudan
| | - Osman Dakein
- Kala azar Research Centre, Faculty of Medicine and Health Sciences, University of Gedarif, Gedarif, Sudan
| | - Bashir Alsharif
- Medical Entomology Department, Federal Ministry of Health, Khartoum, Sudan
| | | | - Omran F Osman
- Department of Zoology, Faculty of Science, University of Khartoum, Khartoum, Sudan
| | - Bakri Y M Nour
- Department of Medical Parasitology, Faculty of Medical Laboratory Sciences, University of Gezira, Wad Medani, Sudan
| | - Gamal Hassan Mohamed
- Department of Biostatistics, Epidemiology and Scientific Computing, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Ricardo Molina
- Laboratorio de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Ana Vidal-López
- Laboratorio de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Ramón Díaz-Regañón
- Laboratorio de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | | | | | - Orin Courtenay
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, UK
| | - Dia-Eldin Elnaiem
- Department of Natural Sciences, University of Maryland Eastern Shore, Princess Anne, Maryland, USA
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Alvar J, Beca-Martínez MT, Argaw D, Jain S, Aagaard-Hansen J. Social determinants of visceral leishmaniasis elimination in Eastern Africa. BMJ Glob Health 2023; 8:e012638. [PMID: 37380365 PMCID: PMC10410987 DOI: 10.1136/bmjgh-2023-012638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/05/2023] [Indexed: 06/30/2023] Open
Abstract
Visceral leishmaniasis is a vector-borne, protozoan disease with severe public health implications. Following the successful implementation of an elimination programme in South Asia, there is now a concerted endeavour to replicate these efforts in Eastern Africa based on the five essential elimination pillars of case management, integrated vector management, effective surveillance, social mobilisation and operational research. This article highlights how key social determinants (SD) of health (poverty, sociocultural factors and gender, housing and clustering, migration and the healthcare system) operate at five different levels (socioeconomic context and position, differential exposure, differential vulnerability, differential outcomes and differential consequences). These SD should be considered within the context of increasing the success of the five-pillar elimination programme and reducing inequity in health.
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Affiliation(s)
- Jorge Alvar
- Social Medicine, Royal Academy of Medicine, Madrid, Spain
| | | | - Daniel Argaw
- Neglected Tropical Diseases, World Health Organization, Geneva, GE, Switzerland
| | - Saurabh Jain
- Neglected Tropical Diseases, World Health Organization, Geneva, GE, Switzerland
| | - Jens Aagaard-Hansen
- Health Promotion, Steno Diabetes Center Copenhagen, Herlev, Capital Region, Denmark
- Health Research, University of the Witwatersrand Johannesburg Faculty of Health Sciences, Johannesburg, Gauteng, South Africa
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Trájer AJ. The potential impact of climate change on the seasonality of Phlebotomus neglectus, the vector of visceral leishmaniasis in the East Mediterranean region. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2021; 31:932-950. [PMID: 31859534 DOI: 10.1080/09603123.2019.1702150] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
Phlebotomus neglectus is one of the most important vectors of visceral leishmaniasis in Southeast Europe and Asia Minor. It was aimed to study the impact of climate change on the seasonality and the range of the species for 2014-2060. In the inland areas of Asia Minor, the Balkan Peninsula and the Carpathian Basin the elongation of the activity season will reach or exceed the two months in the middle of the 21st century compared to the end of the 20th century. The most affected regions are the middle elevations of the mountainous regions and the plains of the northern distribution areas. In some areas of the southern distribution border, the season is expected to shorten. In the Apennine Peninsula, mainly the mountainous areas could be impacted notably by climate change. The results indicate the potential spread of leishmaniasis in Southeast Europe due to the increasing environmental suitability of the region.
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An integrative approach to identify sand fly vectors of leishmaniasis in Ethiopia by morphological and molecular techniques. Parasit Vectors 2020; 13:580. [PMID: 33203446 PMCID: PMC7672994 DOI: 10.1186/s13071-020-04450-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/30/2020] [Indexed: 12/17/2022] Open
Abstract
Background Ethiopia is affected by human leishmaniasis caused by several Leishmania species and transmitted by a variety of sand fly vectors of the genus Phlebotomus. The sand fly fauna in Ethiopia is highly diverse and some species are closely related and similar in morphology, resulting in difficulties with species identification that requires deployment of molecular techniques. DNA barcoding entails high costs, requires time and lacks reference sequences for many Ethiopian species. Yet, proper species identification is pivotal for epidemiological surveillance as species differ in their actual involvement in transmission cycles. Recently, protein profiling using MALDI-TOF mass spectrometry has been introduced as a promising technique for sand fly identification. Methods In our study, we used an integrative taxonomic approach to identify most of the important sand fly vectors of leishmaniasis in Ethiopia, applying three complementary methods: morphological assessment, sequencing analysis of two genetic markers, and MALDI-TOF MS protein profiling. Results Although morphological assessment resulted in some inconclusive identifications, both DNA- and protein-based techniques performed well, providing a similar hierarchical clustering pattern for the analyzed species. Both methods generated species-specific sequences or protein patterns for all species except for Phlebotomus pedifer and P. longipes, the two presumed vectors of Leishmania aethiopica, suggesting that they may represent a single species, P. longipes Parrot & Martin. All three approaches also revealed that the collected specimens of Adlerius sp. differ from P. (Adlerius) arabicus, the only species of Adlerius currently reported in Ethiopia, and molecular comparisons indicate that it may represent a yet undescribed new species. Conclusions Our study uses three complementary taxonomical methods for species identification of taxonomically challenging and yet medically import Ethiopian sand flies. The generated MALDI-TOF MS protein profiles resulted in unambiguous identifications, hence showing suitability of this technique for sand fly species identification. Furthermore, our results contribute to the still inadequate knowledge of the sand fly fauna of Ethiopia, a country severely burdened with human leishmaniasis.![]()
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Sales KGDS, Miranda DEDO, da Silva FJ, Otranto D, Figueredo LA, Dantas-Torres F. Evaluation of different storage times and preservation methods on phlebotomine sand fly DNA concentration and purity. Parasit Vectors 2020; 13:399. [PMID: 32762709 PMCID: PMC7412822 DOI: 10.1186/s13071-020-04270-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 07/30/2020] [Indexed: 12/15/2022] Open
Abstract
Background Different methods have been used to preserve phlebotomine sand flies for research purposes, including for taxonomic studies and detection of Leishmania spp. Here, we evaluated the effect of various preservation methods at different storage times on phlebotomine sand fly DNA concentration and purity. Methods Field-collected phlebotomine sand flies were individually stored in 70% ethanol (G1) and 95% ethanol (G2) at room temperature, 70% ethanol (G3) and 95% ethanol (G4) at 8 °C or frozen dry (i.e. no preservation solution) at − 20 °C (G5). DNA concentration and purity were assessed at various storage times (T1, ≤ 12 h; T2, 3 months; T3, 6 months; T4, 9 months; and T5, 12 months). Fragments of the cytochrome c oxidase subunit 1 (cox1) and cacophony (CAC) genes of phlebotomine sand flies were also amplified. Results Mean DNA concentration (P = 0.178) and 260/280 purity ratios (P = 0.584) did not vary significantly among various preservation methods and storage times. Within each group, DNA concentration varied in G1 (Kruskal-Wallis H-test, P = 0.009) for T3 vs T4 (Dunn’s post-hoc, P < 0.05), and in G2 (Kruskal-Wallis H-test, P = 0.004) for T1 vs T2 and T1 vs T4 (Dunn’s post-hoc, P < 0.05). For 260/280 purity ratios, the only statistically significant difference was found for G5 (Kruskal-Wallis H-test, P = 0.020) between T1 vs T4 (Dunn’s post-hoc test, P < 0.05). The cox1 and CAC genes were successfully amplified, regardless of the preservation method and storage time; except in one sample from G2 at T1, for which the CAC gene failed to amplify. Conclusions The preservation methods and storage times herein evaluated did not affect the concentration and purity of DNA samples obtained from field-collected phlebotomine sand flies, for up to 12 months. Furthermore, these preservation methods did not interfere with PCR amplification of CAC and cox1 genes, being suitable for molecular analyses under the conditions studied herein.![]()
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Affiliation(s)
| | | | - Fernando José da Silva
- Department of Immunology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation (Fiocruz), Recife, Brazil
| | - Domenico Otranto
- Department of Veterinary Medicine, University of Bari, Valenzano, Italy.,Faculty of Veterinary Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Luciana Aguiar Figueredo
- Department of Immunology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation (Fiocruz), Recife, Brazil
| | - Filipe Dantas-Torres
- Department of Immunology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation (Fiocruz), Recife, Brazil.
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Pareyn M, Kochora A, Van Rooy L, Eligo N, Vanden Broecke B, Girma N, Merdekios B, Wegayehu T, Maes L, Caljon G, Lindtjørn B, Leirs H, Massebo F. Feeding behavior and activity of Phlebotomus pedifer and potential reservoir hosts of Leishmania aethiopica in southwestern Ethiopia. PLoS Negl Trop Dis 2020; 14:e0007947. [PMID: 32196501 PMCID: PMC7112221 DOI: 10.1371/journal.pntd.0007947] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 04/01/2020] [Accepted: 02/25/2020] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Cutaneous leishmaniasis (CL) is a major public health concern in Ethiopia. However, knowledge about the complex zoonotic transmission cycle is limited, hampering implementation of control strategies. We explored the feeding behavior and activity of the vector (Phlebotomus pedifer) and studied the role of livestock in CL transmission in southwestern Ethiopia. METHODS Blood meal origins of engorged sand flies were determined by sequencing host DNA. A host choice experiment was performed to assess the feeding preference of P. pedifer when humans and hyraxes are equally accessible. Ear and nose biopsies from livestock were screened for the presence of Leishmania parasites. Sand flies were captured indoor and outdoor with human landing catches and CDC light traps to determine at which time and where P. pedifer is mostly active. PRINCIPAL FINDINGS A total of 180 P. pedifer sand flies were found to bite hosts of 12 genera. Humans were the predominant blood meal source indoors (65.9%, p < 0.001), while no significant differences were determined outdoors and in caves. In caves, hyraxes were represented in blood meals equally as humans (45.5% and 42.4%, respectively), but the host choice experiment revealed that sand flies have a significant preference for feeding on hyraxes (p = 0.009). Only a single goat nose biopsy from 412 animal samples was found with Leishmania RNA. We found that P. pedifer is predominantly endophagic (p = 0.003), but occurs both indoors and outdoors. A substantial number of sand flies was active in the early evening, which increased over time reaching its maximum around midnight. CONCLUSION In contrast to earlier suggestions of exclusive zoonotic Leishmania transmission, we propose that there is also human-to-human transmission of CL in southwestern Ethiopia. Livestock does not play a role in CL transmission and combined indoor and outdoor vector control measures at night are required for efficient vector control.
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Affiliation(s)
- Myrthe Pareyn
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
- * E-mail: (MP); (FM)
| | - Abena Kochora
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | - Luca Van Rooy
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | - Nigatu Eligo
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | | | - Nigatu Girma
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | - Behailu Merdekios
- Public Health Department, Arba Minch University, Arba Minch, Ethiopia
| | - Teklu Wegayehu
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Bernt Lindtjørn
- Centre for International Health, University of Bergen, Bergen, Norway
| | - Herwig Leirs
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | - Fekadu Massebo
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
- * E-mail: (MP); (FM)
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Kirstein OD, Skrip L, Abassi I, Iungman T, Horwitz BZ, Gebresilassie A, Spitzova T, Waitz Y, Gebre-Michael T, Volf P, Hailu A, Warburg A. A fine scale eco-epidemiological study on endemic visceral leishmaniasis in north ethiopian villages. Acta Trop 2018; 183:64-77. [PMID: 29621537 PMCID: PMC5956276 DOI: 10.1016/j.actatropica.2018.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/21/2018] [Accepted: 04/01/2018] [Indexed: 12/03/2022]
Abstract
We conducted fine-scale eco-epidemiological analyses of factors associated with visceral leishmaniasis transmission. The population densities of Phlebotomus orientalis, the vector, were negatively correlated with distance from vertisols. Sero-positivity to Ph. orientalis saliva, was found in people living close to vertisol areas. Apparent clustering of infections indicates that transmission occurs around houses located close to vertisols. Our data suggest that asymptomatic individuals serve as reservoir hosts for anthroponotic transmission inside villages.
Visceral Leishmaniasis (VL) is a disseminated protozoan infection caused by Leishmania donovani that affects almost half a million people annually. In Northern Ethiopia, VL is common in migrant agricultural laborers returning from the lowland sesame fields of Metema and Humera. Recent VL foci have emerged in resident rural populations near the town. In the current study, we evaluate multilevel entomological, epidemiological and ecological factors associated with infection and disease through fine-scale eco-epidemiological analyses in three villages. Satellite images showed that villages constructed in or close to vertisols, were likely to become endemic for VL. Vertisols or black-cotton soil, are characterized by high contents of smectitic clay minerals, which swell when hydrated and shrink upon desiccation, causing extensive deep cracking during the dry season. The population densities of Phlebotomus orientalis, the vector, were negatively correlated with distance from vertisols and persons living close to vertisols were more likely to be bitten by sand flies, as evidenced by sero-positivity to Ph. orientalis saliva. Apparent (albeit non-significant) clustering of VL cases and abundant asymptomatic infections close to vertisols, suggest anthroponotic transmission around houses located close to vertisols. Comparable rates of male and female volunteers, mostly under 15 years of age, were infected with L. donovani but a significantly higher proportion of males succumbed to VL indicating a physiological gender-linked male susceptibility. Our data suggest that the abundant infected persons with high parasitemias who remain asymptomatic, may serve as reservoir hosts for anthroponotic transmission inside villages. Only limited insights on the transmission dynamics of L. donovani were gained by the study of environmental factors such as presence of animals, house structure and vegetation cover.
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Affiliation(s)
- Oscar David Kirstein
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research, Israel-Canada [IMRIC], The Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Israel.
| | - Laura Skrip
- Department of Biostatistics, School of Public Health, Yale University,60 College street, New Haven, CT, 06520, USA, USA
| | - Ibrahim Abassi
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research, Israel-Canada [IMRIC], The Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Israel
| | - Tamara Iungman
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research, Israel-Canada [IMRIC], The Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Israel
| | - Ben Zion Horwitz
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research, Israel-Canada [IMRIC], The Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Israel
| | - Araya Gebresilassie
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia, Ethiopia
| | - Tatiana Spitzova
- Department of Parasitology, Faculty of Science, Charles University, Vinicna 7, 128 44, Prague 2, Czech Republic, Czech Republic
| | - Yoni Waitz
- Department of Geography and Environmental Studies, Haifa University, Haifa, Israel, Israel
| | - Teshome Gebre-Michael
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia, Ethiopia
| | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Vinicna 7, 128 44, Prague 2, Czech Republic, Czech Republic
| | - Asrat Hailu
- Dept. of Microbiology, Immunology and Parasitology, Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia, Ethiopia
| | - Alon Warburg
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research, Israel-Canada [IMRIC], The Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Israel
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Bsrat A, Berhe M, Gadissa E, Taddele H, Tekle Y, Hagos Y, Abera A, G/micael M, Alemayhu T, Gugsa G, Aseffa A. Serological investigation of visceral Leishmania infection in human and its associated risk factors in Welkait District, Western Tigray, Ethiopia. Parasite Epidemiol Control 2018; 3:13-20. [PMID: 29774295 PMCID: PMC5952676 DOI: 10.1016/j.parepi.2017.10.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 12/02/2022] Open
Abstract
Visceral leishmaniasis (VL) is major neglected public health problem in terms of geographical spread and incidence in Ethiopia. Magnitude, public health impact and dynamics of VL were not well studied in Welkait District, Western Tigray, though the area is known for VL. Hence, this study aimed to determine sero-prevalence of human VL and associated risk factors in Welkait as new foci. A cross sectional study design was employed in this study. Two stage stratified random sampling method was used to select study participants. Hence, a total of 329 human study participants were included for serological survey using ITleish and leishmanin skin tests. Semi structured questionnaire was also used to identify VL associated risk factors. Univariate and multivariate logistic regression statistical methods were used to determine the degree of association. The overall sero-prevalence of human VL in the study area was found to be 8.81%. Statistical significant difference in the prevalence of the disease was found among Sub-districts, sex, re-settlement, sleeping outdoor and dog ownership (P < 0.05). Participants who resettled from their original place were found 2 times (AOR = 2.143; 95% CI = 1.02, 14.20) more vulnerable to VL infection. Those who had an experience of sleeping outdoor were found almost 4 times (AOR = 4.29; 95% CI = 1.58, 11.69) more likely to be at risk of acquiring VL infection than those sleep indoor. Furthermore, individuals who owned dogs were 3 times more prone to the VL infection than their counterparts (AOR = 3.37; 95% CI = 1.29, 8.76). Alarming sero-positivity of human VL was recorded from new foci. Hence, it is recommended to improve the VL health services in the study area. The investigation also invites further study on VL dynamics in the study area.
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Affiliation(s)
- Abrha Bsrat
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Mebrahtu Berhe
- Veterinary Drug and Feed Administration and Control Authority, Tigray, Ethiopia
| | | | - Habtamu Taddele
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Yohannes Tekle
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Yohannes Hagos
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Adugna Abera
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Messele G/micael
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Tehetna Alemayhu
- Mekelle University College of Veterinary Medicine, Mekelle, Ethiopia
| | - Getachew Gugsa
- Wollo University College of Veterinary Medicine, Dessie, Ethiopia
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
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Aklilu E, Gebresilassie A, Yared S, Kindu M, Tekie H, Balkew M, Warburg A, Hailu A, Gebre-Michael T. Comparative study on the nocturnal activity of phlebotomine sand flies in a highland and lowland foci of visceral leishmaniasis in north-western Ethiopia with special reference to Phlebotomus orientalis. Parasit Vectors 2017; 10:393. [PMID: 28830569 PMCID: PMC5568301 DOI: 10.1186/s13071-017-2339-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/17/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Leishmania donovani, the causative agent of visceral leishmaniasis (VL), is most probably vectored by Phlebotomus orientalis in north-western Ethiopia. The aim of this study was to determine and compare the nocturnal activity patterns of Ph. orientalis in VL endemic foci of Libo-Kemkem (highland) and Metema (lowland) districts of north-western Ethiopia. METHODS Sampling of sand flies was conducted bimonthly from January-May 2012 in the highland and from March-June 2013 in the lowland. Sand flies were sampled using two CDC light traps placed in compounds occupied by both cattle and humans. Sampling of sand flies started at 18:00 h and ended at 06:00 h. Every hour, a cage was replaced by another cage. RESULTS In total, 9479 nocturnally active sand flies were collected from both study areas. Six Phlebotomus species (Ph. orientalis, Ph. duboscqi, Ph. papatasi, Ph. bergeroti, Ph. rodhaini and Ph. martini) and several Sergentomyia spp. were identified. In both areas, of the six Phlebotomus spp., Ph. orientalis was the preponderate. In the highland, the hourly activity pattern of Ph. orientalis females was higher before midnight with a peak in density between 22:00-23:00 h, whereas in the lowland after midnight between 03:00-04:00 h. CONCLUSIONS The present study showed that Ph. orientalis females exhibited different nocturnal activity patterns with a peak in the early part of the night in the highland and in the latter part of the night in the lowland areas. As the risk of acquiring L. donovani infections vary in the two areas, appropriate control strategies should be developed according to the activity of Ph. orientalis in the respective areas.
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Affiliation(s)
- Esayas Aklilu
- Department of Biology, Mada Walabu University, Bale-Robe, Ethiopia.
| | | | - Solomon Yared
- Department of Biology, Jigjiga University, Jigjiga, Ethiopia
| | - Mizan Kindu
- Department of Microbiology and Parasitology, Mada Walabu University, Bale-Robe, Ethiopia
| | - Habte Tekie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Meshesha Balkew
- Aklilu Lemma Institutes of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Alon Warburg
- Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel
| | - Asrat Hailu
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Teshome Gebre-Michael
- Aklilu Lemma Institutes of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
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11
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Gebresilassie A, Abbasi I, Aklilu E, Yared S, Kirstein OD, Moncaz A, Tekie H, Balkew M, Warburg A, Hailu A, Gebre-Michael T. Host-feeding preference of Phlebotomus orientalis (Diptera: Psychodidae) in an endemic focus of visceral leishmaniasis in northern Ethiopia. Parasit Vectors 2015; 8:270. [PMID: 25963759 PMCID: PMC4432826 DOI: 10.1186/s13071-015-0883-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/04/2015] [Indexed: 11/16/2022] Open
Abstract
Background Blood-feeding behavior studies are important for estimating the efficiency of pathogen transmission and assessing the relative human disease risk. However, in Ethiopia and other parts of East Africa there are large remaining gaps in identifying the feeding habits of Phlebotomus orientalis, the vector of Leishmania donovani. The aim of the study was to determine the blood feeding patterns of P. orientalis in Tahtay Adiyabo district, northern Ethiopia. Methods For bloodmeal analysis, sandflies were collected from three different villages of Tahtay Adiyabo district using CDC light traps, sticky traps, and pyrethrum spray catches. Bloodmeal of engorged female sandflies was identified using cytochrome (cyt) b-PCR and reverse-line blotting (RLB) and enzyme linked immunosorbent assay (ELISA) assays. Results Most (637/641) of the females analyzed were P. orientalis. Successful identification of the host from bloodmeals was achieved in 83.03 and 92.1 % using cyt b PCR-RLB and ELISA, respectively. Bloodmeal analysis of P. orientalis females revealed that they have a range of hosts with predominant preference to bovines followed by donkey, human, goat, sheep, dog, and camel. Conclusion Results obtained from bloodmeal analyses demonstrate that the feeding preference of P. orientalis is mainly zoophilic, which could vary depending on the availability of hosts.
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Affiliation(s)
- Araya Gebresilassie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia. .,Department of Biology, College of Natural Science, Jigjiga University, Jigjiga, Ethiopia.
| | - Ibrahim Abbasi
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Essayas Aklilu
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Solomon Yared
- Department of Biology, College of Natural Science, Jigjiga University, Jigjiga, Ethiopia.
| | - Oscar David Kirstein
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Aviad Moncaz
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Habte Tekie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Meshesha Balkew
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Alon Warburg
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Asrat Hailu
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Teshome Gebre-Michael
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
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12
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Gebresilassie A, Kirstein OD, Yared S, Aklilu E, Moncaz A, Tekie H, Balkew M, Warburg A, Hailu A, Gebre-Michael T. Nocturnal periodicity of Phlebotomus (Larroussius) orientalis (Diptera: Psychodidae) in an endemic focus of visceral leishmaniasis in Northern Ethiopia. Parasit Vectors 2015; 8:186. [PMID: 25889314 PMCID: PMC4381670 DOI: 10.1186/s13071-015-0804-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 03/17/2015] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Phlebotomus orientalis is the major vector of the intramacrophage protozoa, Leishmania donovani, the etiological agent of visceral leishmaniasis (VL) in northern Ethiopia and Sudan. The objective of this study was to determine the nocturnal periodicity of P. orientalis in the VL endemic focus of Tahtay Adiyabo district, northern Ethiopia. METHODS Sandflies were collected using CDC light traps by changing collecting bags at an hourly interval from dusk to dawn for six months (January-June 2013) from outdoors (i.e. peri-domestic and agricultural fields). Sandfly specimens collected in the study were identified to species level and counted. RESULTS In total, 21,716 nocturnally active sandfly specimens, which belong to two genera (i.e., Phlebotomus and Sergentomyia) were collected and identified. In the collection, P. orientalis, the dominant species in the genus Phlebotomus, constituted 33.79% while Sergentomyia spp. comprised 65.44%. Analysis of data showed that activity of P. orientalis females increased from 18:00 to 24:00 hours, with a peak after midnight (24:00-03:00 hrs). Likewise, activity of parous P. orientalis females was found to be unimodal, peaking at 24-01:00 hrs. CONCLUSION P. orientalis females had marked nocturnal activity, which peak after midnight. Similarly, the epidemiologically dangerous parous females generally were more active after midnight. Therefore, humans are at risk of L. donovani infections through the bite of P. orientalis possibly between midnight and dawn.
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Affiliation(s)
- Araya Gebresilassie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
- Department of Biology, College of Natural Science, Jigjiga University, Jigjiga, Ethiopia.
| | - Oscar David Kirstein
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Solomon Yared
- Department of Biology, College of Natural Science, Jigjiga University, Jigjiga, Ethiopia.
| | - Essayas Aklilu
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Aviad Moncaz
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Habte Tekie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Meshesha Balkew
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Alon Warburg
- Department of Microbiology and Molecular Genetics, The Institute of Medical Research Israel-Canada The Kuvin Center for the Study of Infectious and Tropical Diseases, Faculty of Medicine, The Hebrew University, Hadassah Medical School, Jerusalem, Israel.
| | - Asrat Hailu
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Teshome Gebre-Michael
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
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