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Djiman TA, Biguezoton AS, Saegerman C. Tick-Borne Diseases in Sub-Saharan Africa: A Systematic Review of Pathogens, Research Focus, and Implications for Public Health. Pathogens 2024; 13:697. [PMID: 39204297 PMCID: PMC11356977 DOI: 10.3390/pathogens13080697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2024] [Revised: 08/11/2024] [Accepted: 08/12/2024] [Indexed: 09/03/2024] Open
Abstract
Sub-Saharan Africa, with its hot and humid climate, is a conducive zone for tick proliferation. These vectors pose a major challenge to both animal and human health in the region. However, despite the relevance of emerging diseases and evidence of tick-borne disease emergence, very few studies have been dedicated to investigating zoonotic pathogens transmitted by ticks in this area. To raise awareness of the risks of tick-borne zoonotic diseases in sub-Saharan Africa, and to define a direction for future research, this systematic review considers the trends of research on tick-borne bacteria, parasites, and viruses from 2012 to 2023, aiming to highlight the circulation of these pathogens in ticks, cattle, sheep, goats, and humans. For this purpose, three international databases were screened to select 159 papers fitting designed inclusion criteria and used for qualitative analyses. Analysis of these studies revealed a high diversity of tick-borne pathogens in sub-Saharan Africa, with a total of 37 bacterial species, 27 parasite species, and 14 viruses identified. Among these, 27% were zoonotic pathogens, yet only 11 studies investigated their presence in humans. Furthermore, there is growing interest in the investigation of bacteria and parasites in both ticks and ruminants. However, research into viruses is limited and has only received notable interest from 2021 onwards. While studies on the detection of bacteria, including those of medical interest, have focused on ticks, little consideration has been given to these vectors in studies of parasites circulation. Regarding the limited focus on zoonotic pathogens transmitted by ticks, particularly in humans, despite documented cases of emerging zoonoses and the notable 27% proportion reported, further efforts should be made to fill these gaps. Future studies should prioritize the investigation of zoonotic pathogens, especially viruses, which represent the primary emerging threats, by adopting a One Health approach. This will enhance the understanding of their circulation and impact on both human and animal health. In addition, more attention should be given to the risk factors/drivers associated to their emergence as well as the perception of the population at risk of infection from these zoonotic pathogens.
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Affiliation(s)
- Tidjani A. Djiman
- Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULiège), Fundamental and Applied Research for Animals and Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, 4000 Liège, Belgium;
- Vector-Borne Diseases and Biodiversity Unit (UMaVeB), International Research and Development Centre on Livestock in Sub-humid Areas (CIRDES), Bobo-Dioulasso 454, Burkina Faso;
| | - Abel S. Biguezoton
- Vector-Borne Diseases and Biodiversity Unit (UMaVeB), International Research and Development Centre on Livestock in Sub-humid Areas (CIRDES), Bobo-Dioulasso 454, Burkina Faso;
| | - Claude Saegerman
- Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULiège), Fundamental and Applied Research for Animals and Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, 4000 Liège, Belgium;
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Rooney T, Fèvre EM, Villinger J, Brenn-White M, Cummings CO, Chai D, Kamau J, Kiyong'a A, Getange D, Ochieng DO, Kivali V, Zimmerman D, Rosenbaum M, Nutter FB, Deem SL. Coxiella burnetii serostatus in dromedary camels (Camelus dromedarius) is associated with the presence of C. burnetii DNA in attached ticks in Laikipia County, Kenya. Zoonoses Public Health 2024; 71:503-514. [PMID: 38627945 DOI: 10.1111/zph.13127] [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: 07/22/2023] [Revised: 03/07/2024] [Accepted: 03/14/2024] [Indexed: 07/02/2024]
Abstract
AIMS Q fever is a globally distributed, neglected zoonotic disease of conservation and public health importance, caused by the bacterium Coxiella burnetii. Coxiella burnetii normally causes subclinical infections in livestock, but may also cause reproductive pathology and spontaneous abortions in artiodactyl species. One such artiodactyl, the dromedary camel (Camelus dromedarius), is an increasingly important livestock species in semi-arid landscapes. Ticks are naturally infected with C. burnetii worldwide and are frequently found on camels in Kenya. In this study, we assessed the relationship between dromedary camels' C. burnetii serostatus and whether the camels were carrying C. burnetii PCR-positive ticks in Kenya. We hypothesized that there would be a positive association between camel seropositivity and carrying C. burnetii PCR-positive ticks. METHODS AND RESULTS Blood was collected from camels (N = 233) from three herds, and serum was analysed using commercial ELISA antibody test kits. Ticks were collected (N = 4354), divided into pools of the same species from the same camel (N = 397) and tested for C. burnetii and Coxiella-like endosymbionts. Descriptive statistics were used to summarize seroprevalence by camel demographic and clinical variables. Univariate logistic regression analyses were used to assess relationships between serostatus (outcome) and tick PCR status, camel demographic variables, and camel clinical variables (predictors). Camel C. burnetii seroprevalence was 52%. Across tick pools, the prevalence of C. burnetii was 15% and Coxiella-like endosymbionts was 27%. Camel seropositivity was significantly associated with the presence of a C. burnetii PCR-positive tick pool (OR: 2.58; 95% CI: 1.4-5.1; p = 0.0045), increasing age class, and increasing total solids. CONCLUSIONS The role of ticks and camels in the epidemiology of Q fever warrants further research to better understand this zoonotic disease that has potential to cause illness and reproductive losses in humans, livestock, and wildlife.
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Affiliation(s)
- Tess Rooney
- Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
- San Diego Zoo Wildlife Alliance, San Diego, California, USA
- School of Veterinary Medicine, University of California, Davis, Davis, California, USA
| | - Eric M Fèvre
- International Livestock Research Institute, Nairobi, Kenya
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Maris Brenn-White
- Institute for Conservation Medicine, Saint Louis Zoo, St. Louis, Missouri, USA
- Santa Cruz County Animal Services Authority, Santa Cruz, California, USA
| | - Charles O Cummings
- Tufts Clinical and Translational Science Institute, Tufts Medical Center, Boston, Massachusetts, USA
| | - Daniel Chai
- One Health Centre, Institute of Primate Research, Nairobi, Kenya
| | - Joseph Kamau
- One Health Centre, Institute of Primate Research, Nairobi, Kenya
| | - Alice Kiyong'a
- International Livestock Research Institute, Nairobi, Kenya
| | - Dennis Getange
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Dickens O Ochieng
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Velma Kivali
- International Livestock Research Institute, Nairobi, Kenya
| | - Dawn Zimmerman
- Global Health Program, Smithsonian Conservation Biology Institute, Washington, District of Columbia, USA
- Veterinary Initiative for Endangered Wildlife, Bozeman, Montana, USA
- Department of Epidemiology of Microbial Disease, Yale School of Public Health, New Haven, Connecticut, USA
| | - Marieke Rosenbaum
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Felicia B Nutter
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Sharon L Deem
- Institute for Conservation Medicine, Saint Louis Zoo, St. Louis, Missouri, USA
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Kamau MW, Witte C, Goosen W, Mutinda M, Villinger J, Getange D, Khogali R, von Fricken ME, Fèvre EM, Zimmerman D, Linton YM, Miller M. Comparison of test performance of a conventional PCR and two field-friendly tests to detect Coxiella burnetii DNA in ticks using Bayesian latent class analysis. Front Vet Sci 2024; 11:1396714. [PMID: 38962707 PMCID: PMC11220323 DOI: 10.3389/fvets.2024.1396714] [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: 03/06/2024] [Accepted: 06/10/2024] [Indexed: 07/05/2024] Open
Abstract
Introduction Coxiella burnetii (C. burnetii)-infected livestock and wildlife have been epidemiologically linked to human Q fever outbreaks. Despite this growing zoonotic threat, knowledge of coxiellosis in wild animals remains limited, and studies to understand their epidemiologic role are needed. In C. burnetii-endemic areas, ticks have been reported to harbor and spread C. burnetii and may serve as indicators of risk of infection in wild animal habitats. Therefore, the aim of this study was to compare molecular techniques for detecting C. burnetii DNA in ticks. Methods In total, 169 ticks from wild animals and cattle in wildlife conservancies in northern Kenya were screened for C. burnetii DNA using a conventional PCR (cPCR) and two field-friendly techniques: Biomeme's C. burnetii qPCR Go-strips (Biomeme) and a new C. burnetii PCR high-resolution melt (PCR-HRM) analysis assay. Results were evaluated, in the absence of a gold standard test, using Bayesian latent class analysis (BLCA) to characterize the proportion of C. burnetii positive ticks and estimate sensitivity (Se) and specificity (Sp) of the three tests. Results The final BLCA model included main effects and estimated that PCR-HRM had the highest Se (86%; 95% credible interval: 56-99%), followed by the Biomeme (Se = 57%; 95% credible interval: 34-90%), with the estimated Se of the cPCR being the lowest (24%, 95% credible interval: 10-47%). Specificity estimates for all three assays ranged from 94 to 98%. Based on the model, an estimated 16% of ticks had C. burnetii DNA present. Discussion These results reflect the endemicity of C. burnetii in northern Kenya and show the promise of the PCR-HRM assay for C. burnetii surveillance in ticks. Further studies using ticks and wild animal samples will enhance understanding of the epidemiological role of ticks in Q fever.
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Affiliation(s)
- Maureen W. Kamau
- Mpala Research Centre, Nanyuki, Kenya
- Division of Molecular Biology and Human Genetics, Department of Science, and Innovation – National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research, Faculty of Medicine and Health Sciences, South African Medical Research Council Centre for Tuberculosis Research, Stellenbosch University, Stellenbosch, South Africa
- Global Health Program, Smithsonian National Zoo Conservation Biology Institute, Washington, DC, United States
| | - Carmel Witte
- Division of Molecular Biology and Human Genetics, Department of Science, and Innovation – National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research, Faculty of Medicine and Health Sciences, South African Medical Research Council Centre for Tuberculosis Research, Stellenbosch University, Stellenbosch, South Africa
- The Center for Wildlife Studies, South Freeport, ME, United States
| | - Wynand Goosen
- Division of Molecular Biology and Human Genetics, Department of Science, and Innovation – National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research, Faculty of Medicine and Health Sciences, South African Medical Research Council Centre for Tuberculosis Research, Stellenbosch University, Stellenbosch, South Africa
| | | | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Dennis Getange
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Rua Khogali
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Michael E. von Fricken
- College of Public Health and Health Professionals, Department of Environmental and Global Health University of Florida, Gainesville, FL, United States
| | - Eric Maurice Fèvre
- International Livestock Research Institute, Nairobi, Kenya
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Dawn Zimmerman
- Veterinary Initiative for Endangered Wildlife, Bozeman, MT, United States
| | - Yvonne-Marie Linton
- Walter Reed Biosystematics Unit (WRBU) Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
| | - Michele Miller
- Division of Molecular Biology and Human Genetics, Department of Science, and Innovation – National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research, Faculty of Medicine and Health Sciences, South African Medical Research Council Centre for Tuberculosis Research, Stellenbosch University, Stellenbosch, South Africa
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Kimemia BB, Musila L, Langat S, Odoyo E, Cinkovich S, Abuom D, Yalwala S, Khamadi S, Johnson J, Garges E, Ojwang E, Eyase F. Detection of pathogenic bacteria in ticks from Isiolo and Kwale counties of Kenya using metagenomics. PLoS One 2024; 19:e0296597. [PMID: 38687700 PMCID: PMC11060535 DOI: 10.1371/journal.pone.0296597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/09/2024] [Indexed: 05/02/2024] Open
Abstract
Ticks are arachnid ectoparasites that rank second only to mosquitoes in the transmission of human diseases including bacteria responsible for anaplasmosis, ehrlichiosis, spotted fevers, and Lyme disease among other febrile illnesses. Due to the paucity of data on bacteria transmitted by ticks in Kenya, this study undertook a bacterial metagenomic-based characterization of ticks collected from Isiolo, a semi-arid pastoralist County in Eastern Kenya, and Kwale, a coastal County with a monsoon climate in the southern Kenyan border with Tanzania. A total of 2,918 ticks belonging to 3 genera and 10 species were pooled and screened in this study. Tick identification was confirmed through the sequencing of the Cytochrome C Oxidase Subunit 1 (COI) gene. Bacterial 16S rRNA gene PCR amplicons obtained from the above samples were sequenced using the MinION (Oxford Nanopore Technologies) platform. The resulting reads were demultiplexed in Porechop, followed by trimming and filtering in Trimmomatic before clustering using Qiime2-VSearch. A SILVA database pretrained naïve Bayes classifier was used to classify the Operational Taxonomic Units (OTUs) taxonomically. The bacteria of clinical interest detected in pooled tick assays were as follows: Rickettsia spp. 59.43% of pools, Coxiella burnetii 37.88%, Proteus mirabilis 5.08%, Cutibacterium acnes 6.08%, and Corynebacterium ulcerans 2.43%. These bacteria are responsible for spotted fevers, query fever (Q-fever), urinary tract infections, skin and soft tissue infections, eye infections, and diphtheria-like infections in humans, respectively. P. mirabilis, C. acnes, and C. ulcerans were detected only in Isiolo. Additionally, COI sequences allowed for the identification of Rickettsia and Coxiella species to strain levels in some of the pools. Diversity analysis revealed that the tick genera had high levels of Alpha diversity but the differences between the microbiomes of the three tick genera studied were not significant. The detection of C. acnes, commonly associated with human skin flora suggests that the ticks may have contact with humans potentially exposing them to bacterial infections. The findings in this study highlight the need for further investigation into the viability of these bacteria and the competency of ticks to transmit them. Clinicians in these high-risk areas also need to be appraised for them to include Rickettsial diseases and Q-fever as part of their differential diagnosis.
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Affiliation(s)
- Bryson Brian Kimemia
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
- Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
| | - Lillian Musila
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
- Kenya Medical Research Institute (KEMRI), Centre for Microbiology Research, Nairobi, Kenya
| | - Solomon Langat
- Kenya Medical Research Institute (KEMRI), Centre for Virus Research, Nairobi, Kenya
| | - Erick Odoyo
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
| | - Stephanie Cinkovich
- United States Armed Forces Health Surveillance Division, Global Emerging Infections Surveillance Branch, Silver Spring, Maryland, United States of America
| | - David Abuom
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
| | - Santos Yalwala
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
| | - Samoel Khamadi
- Kenya Medical Research Institute (KEMRI), Centre for Virus Research, Nairobi, Kenya
| | - Jaree Johnson
- United States Armed Forces Pest Management Board, Silver Spring, Maryland, United States of America
| | - Eric Garges
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
| | - Elly Ojwang
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
| | - Fredrick Eyase
- Department of Emerging Infectious Diseases, United States Army Medical Research Directorate-Africa (USAMRD-A), Nairobi, Kenya
- Kenya Medical Research Institute (KEMRI), Centre for Virus Research, Nairobi, Kenya
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Oundo JW, Kalayou S, Bosch QT, Villinger J, Koenraadt CJM, Masiga D. Ticks (Acari: Ixodidae) infesting cattle in coastal Kenya harbor a diverse array of tick-borne pathogens. Ticks Tick Borne Dis 2024; 15:102266. [PMID: 37813003 DOI: 10.1016/j.ttbdis.2023.102266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 07/27/2023] [Accepted: 09/21/2023] [Indexed: 10/11/2023]
Abstract
Ticks and the microbes they transmit have emerged in sub-Saharan Africa as a major threat to veterinary and public health. Although progress has been made in detecting and identifying tick-borne pathogens (TBPs) across vast agroecologies of Kenya, comprehensive information on tick species infesting cattle and their associated pathogens in coastal Kenya needs to be updated and expanded. Ticks infesting extensively grazed zebu cattle in 14 villages were sampled and identified based on morphology and molecular methods and tested for the presence of bacterial and protozoan TBPs using PCR with high-resolution melting analysis and gene sequencing. In total, 3,213 adult ticks were collected and identified as Rhipicephalus appendiculatus (15.8%), R. evertsi (12.8%), R. microplus (11.3%), R. pulchellus (0.1%), Amblyomma gemma (24.1%), A. variegatum (35.1%), Hyalomma rufipes (0.6%), and H. albiparmatum (0.2%). Ticks were infected with Rickettsia africae, Ehrlichia ruminantium, E. minasensis, Theileria velifera and T. parva. Coxiella sp. endosymbionts were detected in the Rhipicephalus and Amblyomma ticks. Co-infections with two and three different pathogens were identified in 6.9% (n = 95/1382) and 0.1% (n = 2/1382) of single tick samples, respectively, with the most common co-infection being R. africae and E. ruminantium (7.2%, CI: 4.6 - 10.6). All samples were negative for Coxiella burnetii, Anaplasma spp. and Babesia spp. Our study provides an overview of tick and tick-borne microbial diversities in coastal Kenya.
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Affiliation(s)
- Joseph Wang'ang'a Oundo
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya; Quantitative Veterinary Epidemiology, Wageningen University & Research, P.O. Box 338 6700AH Wageningen, the Netherlands.
| | - Shewit Kalayou
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Quirine Ten Bosch
- Quantitative Veterinary Epidemiology, Wageningen University & Research, P.O. Box 338 6700AH Wageningen, the Netherlands
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | | | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
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Smit A, Mulandane FC, Wojcik SH, Horak IG, Makepeace BL, Morar-Leather D, Neves L. Sympatry of Amblyomma eburneum and Amblyomma variegatum on African buffaloes and prevalence of pathogens in ticks. Ticks Tick Borne Dis 2023; 14:102247. [PMID: 37651847 DOI: 10.1016/j.ttbdis.2023.102247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/20/2023] [Accepted: 08/17/2023] [Indexed: 09/02/2023]
Abstract
The Amblyomma genus is represented on the African continent by 24 species, out of which 17 are known to occur in different ecological niches of southern Africa. Amblyomma, known for their aggressive hunting behaviour and aptitude as pathogen vectors, are of main concern to travellers, mainly in rural and conservation areas of Africa. In this study, we highlight the overlapping distribution of Amblyomma eburneum and Amblyomma variegatum found on African buffaloes (Syncerus caffer) at Coutada 11, Central Mozambique. In total, 1,039 Amblyomma ticks were collected and morphologically identified using taxonomic keys, and genomic DNA was extracted. They were subjected to reverse line blotting for pathogen identification followed by molecular analysis (COI sequencing) of both tick species. Pathogens such as Ehrlichia ruminantium, Anaplasma centrale, Theileria sp., Babesia sp. and Rickettsia africae were detected, of which R. africae is zoonotic. Ehrlichia ruminantium, R. africae, Theileria mutans and Theileria velifera are well-established pathogens transmitted by Amblyomma ticks; however, Anaplasma spp. and Babesia spp. are not, suggesting residual parasite DNA in the bloodmeal. Little is mentioned in the literature about A. eburneum, including its role as a vector and reservoir for pathogens. In Mozambique A. eburneum is currently restricted to wildlife but the spread of the tick may be observed given the climate change that is occurring. The infection rates for the pathogens in both Amblyomma tick species were lower than expected, but this may be due to the low host density in the forest niche and the innate immunity of these hosts. With the propensity of ticks of the Amblyomma genus to form parapatric distributions, the mechanisms that allows for the overlapping distribution of these two Amblyomma species while maintaining tick species identity is of great interest.
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Affiliation(s)
- Andeliza Smit
- Tick Research Group, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, 0110, South Africa.
| | - Fernando C Mulandane
- Biotechnology Center, Eduardo Mondlane University, Av. Moçambique Km 1.5, Maputo, Mozambique
| | - Stephané H Wojcik
- Tick Research Group, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, 0110, South Africa
| | - Ivan G Horak
- Tick Research Group, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, 0110, South Africa
| | - Benjamin L Makepeace
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, 146 Brownlow Hill, Liverpool L3 5RF, United Kingdom
| | - Darshana Morar-Leather
- Tick Research Group, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, 0110, South Africa
| | - Luis Neves
- Tick Research Group, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, 0110, South Africa; Biotechnology Center, Eduardo Mondlane University, Av. Moçambique Km 1.5, Maputo, Mozambique
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Magesa WS, Haji I, Kinimi E, Nzalawahe JS, Kazwala R. Distribution and molecular identification of ixodid ticks infesting cattle in Kilombero and Iringa Districts, Tanzania. BMC Vet Res 2023; 19:121. [PMID: 37573333 PMCID: PMC10422822 DOI: 10.1186/s12917-023-03652-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 07/14/2023] [Indexed: 08/14/2023] Open
Abstract
BACKGROUND Hard ticks infesting cattle are vectors of Tick-borne diseases that causes major public health problems and considerable socioeconomic losses to the livestock industry in tropical and subtropical countries. A repeated cross-sectional study was carried out by collecting ticks on cattle during the wet and dry seasons from January to August 2021 in order to determine hard tick prevalence, distribution, and abundance on cattle in Kilombero and Iringa Districts of Tanzania. The collected ticks were identified morphologically using published morphological keys under a stereomicroscope and confirmed by polymerase chain reaction (PCR) and sequencing. RESULTS Out of 740 examined cattle, 304, (41.08%) were infested with ticks. In total, 1,780 ticks were counted on one side of the animal's body and doubled, whereby resulting in a total of 3,560 ticks were recorded. Individual tick burden ranged from n = 2 to 82 ticks per animal, with a mean tick burden of n = 11.7 ± 0.68 per animal. A total of 1,889 ticks were collected from infected cattle including 109 additional ticks observed while collecting ticks based on the animal's posture when restrained to the ground. Out of 1,889 ticks, nine species from three genera were identified morphologically: 1,377 fit in the genus Rhipicephalus, 459 to the genus of Amblyomma, and 53 to the genus Hyalomma. Rhipicephalus microplus was the most prevalent (n = 909, 48.1%), followed by Rhipicephalus evertsi (n = 310, 16.4%), Amblyomma lepidum (n = 310, 16.4%), Rhipicephalus appendiculatus (n = 140, 7.4%), Amblyomma gemma (n = 120, 6.4%), Hyalomma rufipes (n = 50, 2.6%), Amblyomma variegatum (n = 29, 1.5%), Rhipicephalus decoloratus (n = 18, 1.0%), while the least common was Hyalomma albiparmatum (n = 3, 0.2%). Tick diversity was higher in Iringa compared to Kilombero District. Tick prevalence was higher in wet season (n = 148, 41.11%). Ticks were widely distributed in different parts of the host body, with the highest distribution on zone 4 (n = 1,060, 56.11%), which includes groin, flank, abdomen, and around inner thigh of the hind legs and the lowest distribution on zone 2 (n = 14, 0.74%), which includes the back surface of the body. Both Amblyomma lepidum and Rhipicephalus microplus species were found in all the five body zones, and with the highest proportions recorded on zone 4: A. lepidum (n = 209, 67.42%) and R. microplus (n = 714, 78.55%). The nine tick species identified morphologically were also confirmed using molecular methods. However, during sequencing, two species (Rhipicephalus appendiculatus and R. decoloratus) had poor quality sequences and were excluded from the sequence analysis. Sequencing results indicated high nucleotide identity (96-100%) with sequences available in GenBank and Barcode of Life Database (BOLD). The phylogenetic analysis of partial mitochondrial COI and 16S rRNA gene sequences of ticks were used to confirm the morphological identification. CONCLUSION The results showed a high burden of tick infestation on cattle, which could reduce animal production and potentially increase the risk of tick-borne diseases. Therefore, it is necessary to explore the epidemiological and molecular aspects of various tick species in other regions of Tanzania.
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Affiliation(s)
- Walter S Magesa
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania.
| | - Isihaka Haji
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
| | - Edson Kinimi
- Department of Veterinary Physiology, Biochemistry and Pharmacology, Sokoine University of Agriculture, P.O. Box 3017, Morogoro, Tanzania
| | - Jahashi S Nzalawahe
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
| | - Rudovick Kazwala
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania
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Ogola EO, Kopp A, Bastos ADS, Slothouwer I, Omoga DCA, Osalla J, Sang R, Torto B, Junglen S, Tchouassi DP. Phlebovirus diversity in ticks from livestock in arid ecologies in Kenya. Ticks Tick Borne Dis 2023; 14:102087. [PMID: 36459866 DOI: 10.1016/j.ttbdis.2022.102087] [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: 06/04/2022] [Revised: 10/11/2022] [Accepted: 11/09/2022] [Indexed: 11/21/2022]
Abstract
Phleboviruses are emerging pathogens of public health importance. However, their association with ticks is poorly described, particularly in Africa. Here, adult ticks infesting cattle, goats and sheep were collected in two dryland pastoralist ecosystems of Kenya (Baringo and Kajiado counties) and were screened for infection with phleboviruses. Ticks mainly belonged to the species Rhipicephalus appendiculatus, Hyalomma impeltatum, and Hyalomma rufipes. A fragment of the RNA-dependent RNA polymerase (RdRp) gene was identified in thirty of 671 tick pools, of which twenty-nine were from livestock sampled in Baringo county. Phylogenetic analyses revealed that twenty-five sequences were falling in three clades within the group of tick-associated phleboviruses. The sequences of the three clades showed nucleotide distances 8%, 19% and 22%, respectively, to previously known viruses suggesting that these sequence fragments may belong to three distinct viruses. Viruses of the group of tick-associated phleboviruses have been found in several countries and continents but so far have not been associated with disease in humans or animals. In addition, five sequences were found to group with the sandfly-associated phleboviruses Bogoria virus, Perkerra virus and Ntepes virus recently detected in the same region. Further studies are needed to investigate the transmission and maintenance cycles of these viruses, as well as to assess their potential to infect vertebrates.
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Affiliation(s)
- Edwin O Ogola
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya; Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa
| | - Anne Kopp
- Institute of Virology, Charité Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117 Berlin, Germany
| | - Armanda D S Bastos
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa
| | - Inga Slothouwer
- Institute of Virology, Charité Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117 Berlin, Germany
| | - Dorcus C A Omoga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Josephine Osalla
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Rosemary Sang
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya; Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa
| | - Sandra Junglen
- Institute of Virology, Charité Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117 Berlin, Germany.
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya.
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9
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Rialch A, Sankar M, Silamparasan M, Madhusoodan AP, Kharayat NS, Gautam S, Gurav AR, Thankappan S. Molecular detection of Coxiella-like endosymbionts in Rhipicephalus microplus from north India. Vet Parasitol Reg Stud Reports 2022; 36:100803. [PMID: 36436891 DOI: 10.1016/j.vprsr.2022.100803] [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: 06/08/2022] [Revised: 10/21/2022] [Accepted: 10/23/2022] [Indexed: 11/27/2022]
Abstract
Apart from the tick-borne pathogens affecting human and animal health, ticks also harbor various non-pathogenic endosymbionts with dynamic ecological interactions. These endosymbionts are unexplored from the Indian ticks; hence this pilot study was conducted. Seventy-nine ticks were collected from Nainital district of Uttarakhand state of north India and were identified as Rhipicephalus microplus morphologically and by molecular analysis. PCR and sequence analysis were carried out to detect the presence of Rickettsia-like, Coxiella-like and Francisella-like endosymbionts in these ticks. Based on the partial 16S rRNA gene sequence, Coxiella-like endosymbiont (CLE) was detected in the adult and other life-cycle stages of ticks with 96.6-97.7% nucleotide sequence identity with the published CLE sequences from GenBank. The phylogenetic analysis revealed that the CLE from R. microplus were clustered with the CLE from other Rhipicephalus species. All these CLE formed distinct clades from the pathogenic Coxiella burnetii. None of the tick samples was found positive for Rickettsia-like and Francisella-like endosymbionts in the present study. We also demonstrated the vertical transmission of CLE from surface sterilized and laboratory reared fully engorged adult females to the eggs and the larvae. However, large scale studies are to be conducted to detect various endosymbionts and endosymbiont-tick associations in the Indian tick species and to explore these associations for tick and tick-borne disease control.
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Affiliation(s)
- Ajayta Rialch
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India.
| | - M Sankar
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - M Silamparasan
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - A P Madhusoodan
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - Nitish Singh Kharayat
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - Siddharth Gautam
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - Amol Ramdas Gurav
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
| | - Sabrinath Thankappan
- Division of Temperate Animal Husbandry, ICAR-Indian Veterinary Research Institute, Mukteswar Campus, Nainital, Uttrakhand 263138, India
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10
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Chiuya T, Villinger J, Falzon LC, Alumasa L, Amanya F, Bastos ADS, Fèvre EM, Masiga DK. Molecular screening reveals non-uniform malaria transmission in western Kenya and absence of Rickettsia africae and selected arboviruses in hospital patients. Malar J 2022; 21:268. [PMID: 36115978 PMCID: PMC9482282 DOI: 10.1186/s12936-022-04287-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 09/07/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
In sub-Saharan Africa, malaria is the common diagnosis for febrile illness and related clinical features, resulting in the under-diagnosis of other aetiologies, such as arboviruses and Rickettsia. While these may not be significant causes of mortality in malaria-endemic areas, they affect the daily life and performance of affected individuals. It is, therefore, important to have a clear picture of these other aetiologies to institute correct diagnoses at hospitals and improve patient outcomes.
Methods
Blood samples were collected from patients with fever and other clinical features associated with febrile illness at selected hospitals in the malaria-endemic counties of Busia, Bungoma, and Kakamega, and screened for Crimean-Congo haemorrhagic fever, Sindbis, dengue and chikungunya viruses, Rickettsia africae, and Plasmodium spp. using high-throughput real-time PCR techniques. A logistic regression was performed on the results to explore the effect of demographic and socio-economic independent variables on malaria infection.
Results
A total of 336 blood samples collected from hospital patients between January 2018 and February 2019 were screened, of which 17.6% (59/336) were positive for Plasmodium falciparum and 1.5% (5/336) for Plasmodium malariae. Two patients had dual P. falciparum/P. malariae infections. The most common clinical features reported by the patients who tested positive for malaria were fever and headache. None of the patients were positive for the arboviruses of interest or R. africae. Patients living in Busia (OR 5.2; 95% CI 2.46–11.79; p < 0.001) and Bungoma counties (OR 2.7; 95% CI 1.27–6.16; p = 0.013) had higher odds of being infected with malaria, compared to those living in Kakamega County.
Conclusions
The reported malaria prevalence is in line with previous studies. The absence of arboviral and R. africae cases in this study may have been due to the limited number of samples screened, low-level circulation of arboviruses during inter-epidemic periods, and/or the use of PCR alone as a detection method. Other sero-surveys confirming their circulation in the area indicate that further investigations are warranted.
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11
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Evaluating the efficacy of Mazao Tickoff (Metarhizium anisopliae ICIPE 7) in controlling natural tick infestations on cattle in coastal Kenya: Study protocol for a randomized controlled trial. PLoS One 2022; 17:e0272865. [PMID: 35972927 PMCID: PMC9380929 DOI: 10.1371/journal.pone.0272865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 07/27/2022] [Indexed: 11/19/2022] Open
Abstract
Ticks and tick-borne diseases cause substantial economic losses to the livestock industry in sub-Saharan Africa. Mazao Tickoff is a novel bioacaricide developed for tick control and is based on the entomopathogenic fungus Metarhizium anisopliae sensu lato (s.l.) isolate ICIPE 7. To date, no randomized controlled study has been undertaken to demonstrate the efficacy of this bioacaricide in reducing natural tick infestation on cattle. To this end, this field trial is designed to evaluate the anti-tick efficacy of Mazao Tickoff on cattle in coastal Kenya compared to a standard chemical tick control protocol. In this prospective, multi-center randomized controlled trial, eligible herds will be randomized by the herd size to the intervention arm in a 1:1:1 ratio to either Triatix® (active ingredient: amitraz); Mazao Tickoff (active ingredient: M. anisopliae ICIPE 7); or placebo (excipients of the Mazao Tickoff), with a total enrollment target of 1,077 cattle. Treatments will be dispensed on Day 0 (defined individually as the day each animal receives the first treatment) and thereafter every two weeks until Day 182. Ticks will be counted on every animal in each herd (herds to be included have at least one animal bearing at least one tick on Day 0), and thereafter on bi-weekly intervals until Day 182. The primary efficacy assessments of Mazao Tickoff will be based on the mean percentage reduction in tick counts at each post-treatment follow-up visit compared to the placebo group and the Triatix® arm. Further, the effect of Mazao Tickoff on the prevalence of common cattle pathogens, Anaplasma marginale and Theileria parva, will be determined by assessing incidence and seroprevalence at four different time points. This protocol describes the first rigorous evaluation of the efficacy of Mazao Tickoff and its potential as a viable alternative non-chemical acaricide tool for tick control in Kenya and elsewhere.
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Ogola EO, Kopp A, Bastos ADS, Slothouwer I, Marklewitz M, Omoga D, Rotich G, Getugi C, Sang R, Torto B, Junglen S, Tchouassi DP. Jingmen Tick Virus in Ticks from Kenya. Viruses 2022; 14:1041. [PMID: 35632782 PMCID: PMC9147648 DOI: 10.3390/v14051041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/09/2022] [Accepted: 05/10/2022] [Indexed: 01/29/2023] Open
Abstract
Jingmen tick virus (JMTV) is an arbovirus with a multisegmented genome related to those of unsegmented flaviviruses. The virus first described in Rhipicephalus microplus ticks collected in Jingmen city (Hubei Province, China) in 2010 is associated with febrile illness in humans. Since then, the geographic range has expanded to include Trinidad and Tobago, Brazil, and Uganda. However, the ecology of JMTV remains poorly described in Africa. We screened adult ticks (n = 4550, 718 pools) for JMTV infection by reverse transcription polymerase chain reaction (RT-PCR). Ticks were collected from cattle (n = 859, 18.88%), goats (n = 2070, 45.49%), sheep (n = 1574, 34.59%), and free-ranging tortoises (Leopard tortoise, Stigmochelys pardalis) (n = 47, 1.03%) in two Kenyan pastoralist-dominated areas (Baringo and Kajiado counties) with a history of undiagnosed febrile human illness. Surprisingly, ticks collected from goats (0.3%, 95% confidence interval (CI) 0.1-0.5), sheep (1.8%, 95% CI 1.2-2.5), and tortoise (74.5%, 95% CI 60.9-85.4, were found infected with JMTV, but ticks collected from cattle were all negative. JMTV ribonucleic acid (RNA) was also detected in blood from tortoises (66.7%, 95% CI 16.1-97.7). Intragenetic distance of JMTV sequences originating from tortoise-associated ticks was greater than that of sheep-associated ticks. Phylogenetic analyses of seven complete-coding genome sequences generated from tortoise-associated ticks formed a monophyletic clade within JMTV strains from other countries. In summary, our findings confirm the circulation of JMTV in ticks in Kenya. Further epidemiological surveys are needed to assess the potential public health impact of JMTV in Kenya.
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Affiliation(s)
- Edwin O. Ogola
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa;
| | - Anne Kopp
- Berlin Institute of Health, Institute of Virology, Charité—Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, Chariteplatz 1, 10117 Berlin, Germany; (A.K.); (I.S.); (M.M.)
- German Centre for Infection Research (DZIF), Associated Partner Site Charité, 10117 Berlin, Germany
| | - Armanda D. S. Bastos
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa;
| | - Inga Slothouwer
- Berlin Institute of Health, Institute of Virology, Charité—Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, Chariteplatz 1, 10117 Berlin, Germany; (A.K.); (I.S.); (M.M.)
- German Centre for Infection Research (DZIF), Associated Partner Site Charité, 10117 Berlin, Germany
| | - Marco Marklewitz
- Berlin Institute of Health, Institute of Virology, Charité—Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, Chariteplatz 1, 10117 Berlin, Germany; (A.K.); (I.S.); (M.M.)
- German Centre for Infection Research (DZIF), Associated Partner Site Charité, 10117 Berlin, Germany
| | - Dorcus Omoga
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
| | - Gilbert Rotich
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
| | - Caroline Getugi
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
| | - Rosemary Sang
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
- Kenya Medical Research Institute (KEMRI), Off Raila Odinga Way, Nairobi P.O. Box 54840-00200, Kenya
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria 0028, South Africa;
| | - Sandra Junglen
- Berlin Institute of Health, Institute of Virology, Charité—Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, Chariteplatz 1, 10117 Berlin, Germany; (A.K.); (I.S.); (M.M.)
- German Centre for Infection Research (DZIF), Associated Partner Site Charité, 10117 Berlin, Germany
| | - David P. Tchouassi
- International Centre of Insect Physiology and Ecology, Nairobi P.O. Box 30772-00100, Kenya; (E.O.O.); (D.O.); (G.R.); (C.G.); (R.S.); (B.T.)
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13
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King'ori EM, Obanda V, Nyamota R, Remesar S, Chiyo PI, Soriguer R, Morrondo P. Population genetic structure of the elephant tick Amblyomma tholloni from different elephant populations in Kenya. Ticks Tick Borne Dis 2022; 13:101935. [DOI: 10.1016/j.ttbdis.2022.101935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 02/10/2022] [Accepted: 03/05/2022] [Indexed: 11/25/2022]
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14
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Chiuya T, Villinger J, Masiga DK, Ondifu DO, Murungi MK, Wambua L, Bastos ADS, Fèvre EM, Falzon LC. Molecular prevalence and risk factors associated with tick-borne pathogens in cattle in western Kenya. BMC Vet Res 2021; 17:363. [PMID: 34838023 PMCID: PMC8627057 DOI: 10.1186/s12917-021-03074-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 11/05/2021] [Indexed: 11/29/2022] Open
Abstract
Background Tick-borne pathogens (TBPs) are of global importance, especially in sub-Saharan Africa where they represent a major constraint to livestock production. Their association with human disease is also increasingly recognized, signalling their zoonotic importance. It is therefore crucial to investigate TBPs prevalence in livestock populations and the factors associated with their presence. We set out to identify TBPs present in cattle and to determine associated risk factors in western Kenya, where smallholder livestock production is important for subsistence and market-driven income. Results Tick-borne pathogen infections in blood samples collected from cattle at livestock markets and slaughterhouses between May 2017 and January 2019 were identified by high-resolution melting analysis and sequencing of PCR products of genus-specific primers. Of the 422 cattle sampled, 30.1% (127/422) were infected with at least one TBP, while 8.8% (37/422) had dual infections. Anaplasma spp. (19.7%) were the most prevalent, followed by Theileria (12.3%), Ehrlichia (6.6%), and Babesia (0.2%) spp. Sequence analysis of the TBPs revealed them to be Anaplasma platys-like organisms (13.5%), Theileria velifera (7.4%), Anaplasma marginale (4.9%), Theileria mutans (3.1%), Theileria parva (1.6%), and Babesia bigemina (0.2%). Ehrlichia ruminantium, Rickettsia spp., and arboviruses were not detected. Exotic breeds of cattle were more likely to be infected with A. marginale compared to local breeds (OR: 7.99, 95% CI: 3.04–22.02, p < 0.001). Presence of ticks was a significant predictor for Anaplasma spp. (OR: 2.18, 95% CI: 1.32–3.69, p = 0.003) and Ehrlichia spp. (OR: 2.79, 95% CI: 1.22–7.23, p = 0.022) infection. Cattle sampled at slaughterhouses were more likely to be positive for Anaplasma spp. (OR: 1.64, 95% CI: 1.01–2.70, p = 0.048) and A. marginale (OR: 3.84, 95% CI: 1.43–12.21, p = 0.012), compared to those sampled at livestock markets. Conclusion This study reports TBP prevalence and associated risk factors in western Kenya, factors which are key to informing surveillance and control measures.
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Affiliation(s)
- Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya. .,Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria, 0028, South Africa.
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Dickens O Ondifu
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Maurice K Murungi
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya
| | - Lillian Wambua
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya
| | - Armanda D S Bastos
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria, 0028, South Africa
| | - Eric M Fèvre
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya.,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK
| | - Laura C Falzon
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya. .,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
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15
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Getange D, Bargul JL, Kanduma E, Collins M, Bodha B, Denge D, Chiuya T, Githaka N, Younan M, Fèvre EM, Bell-Sakyi L, Villinger J. Ticks and Tick-Borne Pathogens Associated with Dromedary Camels ( Camelus dromedarius) in Northern Kenya. Microorganisms 2021; 9:1414. [PMID: 34209060 PMCID: PMC8306667 DOI: 10.3390/microorganisms9071414] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 12/17/2022] Open
Abstract
Ticks and tick-borne pathogens (TBPs) are major constraints to camel health and production, yet epidemiological data on their diversity and impact on dromedary camels remain limited. We surveyed the diversity of ticks and TBPs associated with camels and co-grazing sheep at 12 sites in Marsabit County, northern Kenya. We screened blood and ticks (858 pools) from 296 camels and 77 sheep for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. Hyalomma (75.7%), Amblyomma (17.6%) and Rhipicephalus (6.7%) spp. ticks were morphologically identified and confirmed by molecular analyses. We detected TBP DNA in 80.1% of blood samples from 296 healthy camels. "Candidatus Anaplasma camelii", "Candidatus Ehrlichia regneryi" and Coxiella burnetii were detected in both camels and associated ticks, and Ehrlichia chaffeensis, Rickettsia africae, Rickettsia aeschlimannii and Coxiella endosymbionts were detected in camel ticks. We also detected Ehrlichia ruminantium, which is responsible for heartwater disease in ruminants, in Amblyomma ticks infesting camels and sheep and in sheep blood, indicating its endemicity in Marsabit. Our findings also suggest that camels and/or the ticks infesting them are disease reservoirs of zoonotic Q fever (C. burnetii), ehrlichiosis (E. chaffeensis) and rickettsiosis (R. africae), which pose public health threats to pastoralist communities.
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Affiliation(s)
- Dennis Getange
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya
| | - Joel L. Bargul
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya
| | - Esther Kanduma
- Department of Biochemistry, School of Medicine, University of Nairobi, Nairobi P.O. Box 30197-00100, Kenya;
| | - Marisol Collins
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
| | - Boku Bodha
- Directorate of Veterinary Services, County Government of Marsabit, Marsabit P.O. Box 384-60500, Kenya; (B.B.); (D.D.)
| | - Diba Denge
- Directorate of Veterinary Services, County Government of Marsabit, Marsabit P.O. Box 384-60500, Kenya; (B.B.); (D.D.)
| | - Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
| | - Naftaly Githaka
- International Livestock Research Institute, Nairobi P.O. Box 30709-00100, Kenya;
| | - Mario Younan
- Food and Agriculture Organization of the United Nations (FAO), Programme & Operational Support to Syria Crisis, UN cross-border hub, Gaziantep 27010, Turkey;
| | - Eric M. Fèvre
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
- International Livestock Research Institute, Nairobi P.O. Box 30709-00100, Kenya;
| | - Lesley Bell-Sakyi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
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16
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Kobayashi T, Chatanga E, Qiu Y, Simuunza M, Kajihara M, Hang’ombe BM, Eto Y, Saasa N, Mori-Kajihara A, Simulundu E, Takada A, Sawa H, Katakura K, Nonaka N, Nakao R. Molecular Detection and Genotyping of Coxiella-Like Endosymbionts in Ticks Collected from Animals and Vegetation in Zambia. Pathogens 2021; 10:pathogens10060779. [PMID: 34205691 PMCID: PMC8234379 DOI: 10.3390/pathogens10060779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 01/16/2023] Open
Abstract
Ticks are obligate ectoparasites as they require to feed on their host blood during some or all stages of their life cycle. In addition to the pathogens that ticks harbor and transmit to vertebrate hosts, they also harbor other seemingly nonpathogenic microorganisms including nutritional mutualistic symbionts. Tick nutritional mutualistic symbionts play important roles in the physiology of the host ticks as they are involved in tick reproduction and growth through the supply of B vitamins as well as in pathogen maintenance and propagation. Coxiella-like endosymbionts (CLEs) are the most widespread endosymbionts exclusively reported in ticks. Although CLEs have been investigated in ticks in other parts of the world, there is no report of their investigation in ticks in Zambia. To investigate the occurrence of CLEs, their maintenance, and association with host ticks in Zambia, 175 ticks belonging to six genera, namely Amblyomma, Argas, Haemaphysalis, Hyalomma, Ornithodoros, and Rhipicephalus, were screened for CLEs, followed by characterization of CLEs by multi-locus sequence typing of the five Coxiella housekeeping genes (dnaK, groEL, rpoB, 16S rRNA, and 23S rRNA). The results showed that 45.7% (n = 80) were positive for CLEs. The comparison of the tick 16S rDNA phylogenetic tree with that of the CLEs concatenated sequences showed that there was a strong correlation between the topology of the trees. The results suggest that most of the CLEs have evolved within tick species, supporting the vertical transmission phenomenon. However, the negative results for CLE in some ticks warrants further investigations of other endosymbionts that the ticks in Zambia may also harbor.
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Affiliation(s)
- Toshiya Kobayashi
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, N 18 W 9, Kita-ku, Sapporo 060-0818, Japan; (T.K.); (E.C.); (K.K.); (N.N.)
| | - Elisha Chatanga
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, N 18 W 9, Kita-ku, Sapporo 060-0818, Japan; (T.K.); (E.C.); (K.K.); (N.N.)
- Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, Lilongwe University of Agriculture and Natural Resources, Lilongwe P.O. Box 219, Malawi
| | - Yongjin Qiu
- Division of International Research Promotion, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan;
| | - Martin Simuunza
- Department of Diseases Control, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia; (M.S.); (N.S.); (E.S.); (A.T.); (H.S.)
- Africa Centre of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka P.O. Box 32379, Zambia;
| | - Masahiro Kajihara
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan; (M.K.); (Y.E.); (A.M.-K.)
| | - Bernard Mudenda Hang’ombe
- Africa Centre of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka P.O. Box 32379, Zambia;
- Department of ParaClinical Studies, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia
| | - Yoshiki Eto
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan; (M.K.); (Y.E.); (A.M.-K.)
| | - Ngonda Saasa
- Department of Diseases Control, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia; (M.S.); (N.S.); (E.S.); (A.T.); (H.S.)
| | - Akina Mori-Kajihara
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan; (M.K.); (Y.E.); (A.M.-K.)
| | - Edgar Simulundu
- Department of Diseases Control, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia; (M.S.); (N.S.); (E.S.); (A.T.); (H.S.)
- Macha Research Trust, Choma P.O. Box 630166, Zambia
| | - Ayato Takada
- Department of Diseases Control, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia; (M.S.); (N.S.); (E.S.); (A.T.); (H.S.)
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan; (M.K.); (Y.E.); (A.M.-K.)
| | - Hirofumi Sawa
- Department of Diseases Control, School of Veterinary Medicine, The University of Zambia, Lusaka P.O. Box 32379, Zambia; (M.S.); (N.S.); (E.S.); (A.T.); (H.S.)
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, N 20 W10, Kita-ku, Sapporo 001-0020, Japan
| | - Ken Katakura
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, N 18 W 9, Kita-ku, Sapporo 060-0818, Japan; (T.K.); (E.C.); (K.K.); (N.N.)
| | - Nariaki Nonaka
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, N 18 W 9, Kita-ku, Sapporo 060-0818, Japan; (T.K.); (E.C.); (K.K.); (N.N.)
| | - Ryo Nakao
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, N 18 W 9, Kita-ku, Sapporo 060-0818, Japan; (T.K.); (E.C.); (K.K.); (N.N.)
- Correspondence: ; Tel.: +81-11-706-5196
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Tsetse blood-meal sources, endosymbionts and trypanosome-associations in the Maasai Mara National Reserve, a wildlife-human-livestock interface. PLoS Negl Trop Dis 2021; 15:e0008267. [PMID: 33406097 PMCID: PMC7822626 DOI: 10.1371/journal.pntd.0008267] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 01/22/2021] [Accepted: 11/22/2020] [Indexed: 01/06/2023] Open
Abstract
African trypanosomiasis (AT) is a neglected disease of both humans and animals caused by Trypanosoma parasites, which are transmitted by obligate hematophagous tsetse flies (Glossina spp.). Knowledge on tsetse fly vertebrate hosts and the influence of tsetse endosymbionts on trypanosome presence, especially in wildlife-human-livestock interfaces, is limited. We identified tsetse species, their blood-meal sources, and correlations between endosymbionts and trypanosome presence in tsetse flies from the trypanosome-endemic Maasai Mara National Reserve (MMNR) in Kenya. Among 1167 tsetse flies (1136 Glossina pallidipes, 31 Glossina swynnertoni) collected from 10 sampling sites, 28 (2.4%) were positive by PCR for trypanosome DNA, most (17/28) being of Trypanosoma vivax species. Blood-meal analyses based on high-resolution melting analysis of vertebrate cytochrome c oxidase 1 and cytochrome b gene PCR products (n = 354) identified humans as the most common vertebrate host (37%), followed by hippopotamus (29.1%), African buffalo (26.3%), elephant (3.39%), and giraffe (0.84%). Flies positive for trypanosome DNA had fed on hippopotamus and buffalo. Tsetse flies were more likely to be positive for trypanosomes if they had the Sodalis glossinidius endosymbiont (P = 0.0002). These findings point to complex interactions of tsetse flies with trypanosomes, endosymbionts, and diverse vertebrate hosts in wildlife ecosystems such as in the MMNR, which should be considered in control programs. These interactions may contribute to the maintenance of tsetse populations and/or persistent circulation of African trypanosomes. Although the African buffalo is a key reservoir of AT, the higher proportion of hippopotamus blood-meals in flies with trypanosome DNA indicates that other wildlife species may be important in AT transmission. No trypanosomes associated with human disease were identified, but the high proportion of human blood-meals identified are indicative of human African trypanosomiasis risk. Our results add to existing data suggesting that Sodalis endosymbionts are associated with increased trypanosome presence in tsetse flies.
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Chiuya T, Masiga DK, Falzon LC, Bastos ADS, Fèvre EM, Villinger J. Tick-borne pathogens, including Crimean-Congo haemorrhagic fever virus, at livestock markets and slaughterhouses in western Kenya. Transbound Emerg Dis 2020; 68:2429-2445. [PMID: 33142046 PMCID: PMC8359211 DOI: 10.1111/tbed.13911] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/26/2020] [Accepted: 10/31/2020] [Indexed: 12/14/2022]
Abstract
Vectors of emerging infectious diseases have expanded their distributional ranges in recent decades due to increased global travel, trade connectivity and climate change. Transboundary range shifts, arising from the continuous movement of humans and livestock across borders, are of particular disease control concern. Several tick-borne diseases are known to circulate between eastern Uganda and the western counties of Kenya, with one fatal case of Crimean-Congo haemorrhagic fever (CCHF) reported in 2000 in western Kenya. Recent reports of CCHF in Uganda have highlighted the risk of cross-border disease translocation and the importance of establishing inter-epidemic, early warning systems to detect possible outbreaks. We therefore carried out surveillance of tick-borne zoonotic pathogens at livestock markets and slaughterhouses in three counties of western Kenya that neighbour Uganda. Ticks and other ectoparasites were collected from livestock and identified using morphological keys. The two most frequently sampled tick species were Rhipicephalus decoloratus (35%) and Amblyomma variegatum (30%); Ctenocephalides felis fleas and Haematopinus suis lice were also present. In total, 486 ticks, lice and fleas were screened for pathogen presence using established molecular workflows incorporating high-resolution melting analysis and identified through sequencing of PCR products. We detected CCHF virus in Rh. decoloratus and Rhipicephalus sp. cattle ticks, and 82 of 96 pools of Am. variegatum were positive for Rickettsia africae. Apicomplexan protozoa and bacteria of veterinary importance, such as Theileria parva, Babesia bigemina and Anaplasma marginale, were primarily detected in rhipicephaline ticks. Our findings show the presence of several pathogens of public health and veterinary importance in ticks from livestock at livestock markets and slaughterhouses in western Kenya. Confirmation of CCHF virus, a Nairovirus that causes haemorrhagic fever with a high case fatality rate in humans, highlights the risk of under-diagnosed zoonotic diseases and calls for continuous surveillance and the development of preventative measures.
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Affiliation(s)
- Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya.,Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Laura C Falzon
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - Armanda D S Bastos
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Eric M Fèvre
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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Anaplasma and Theileria Pathogens in Cattle of Lambwe Valley, Kenya: A Case for Pro-Active Surveillance in the Wildlife-Livestock Interface. Microorganisms 2020; 8:microorganisms8111830. [PMID: 33233713 PMCID: PMC7699859 DOI: 10.3390/microorganisms8111830] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 02/07/2023] Open
Abstract
Tick-borne pathogens (TBPs) are major constraints to livestock production and a threat to public health in Africa. This cross-sectional study investigated the risk of infection with TBPs in cattle of Lambwe Valley, Kenya. Blood samples of 680 zebu cattle from 95 herds in six geospatial clusters within 5 km of Ruma National Park were screened for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. We detected Anaplasma bovis (17.4%), Anaplasma platys (16.9%), Anaplasma marginale (0.6%), Theileria velifera (40%), and Theileria mutans (25.7%), as well as an Anaplasma sp. (11.6%) that matched recently reported Anaplasma sp. sequences from Ethiopia. Babesia, Rickettsia, and Ehrlichia spp. were not detected. The animal and herd-level prevalences for TBPs were 78.5% (95% confidence intervals (CI): 75.3, 81.5) and 95.8% (95% CI: 91.8, 99.8), respectively. About 31.6% of cattle were co-infected with 13 combinations of TBPs. The prevalence of TBPs differed between clusters and age, but the risk of infection was not associated with sex, herd size, or the distance of homesteads from Ruma. This study adds insight into the epidemiology of TBPs around Ruma and highlights the need for proactive surveillance of TBPs in livestock–wildlife interfaces.
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Akutse KS, Subramanian S, Maniania NK, Dubois T, Ekesi S. Biopesticide Research and Product Development in Africa for Sustainable Agriculture and Food Security – Experiences From the International Centre of Insect Physiology and Ecology (icipe). FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2020. [DOI: 10.3389/fsufs.2020.563016] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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