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Matos CA, Nomboro CF, Gonçalves LR, Cala AC, Sitoe CF, Vinte APR, Mondlane CM, André MR, do Carmo Carrilho M. Molecular diagnosis and characterization of Anaplasma marginale and Ehrlichia ruminantium infecting beef cattle of Maputo Province, Mozambique. BMC Vet Res 2024; 20:185. [PMID: 38730389 PMCID: PMC11084066 DOI: 10.1186/s12917-024-04045-4] [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: 08/03/2023] [Accepted: 04/30/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Members of the Anaplasmataceae family, such as the Anaplasma and Ehrlichia species, cause economic losses and public health risks. However, the exact economic impact has not been comprehensively assessed in Mozambique due to limited data available on its basic epidemiology. Therefore, we investigated the molecular occurrence and identity of Anaplasma and Ehrlichia spp. infecting beef cattle in Maputo province, Mozambique. METHODS A total of 200 whole blood samples were collected from apparently healthy beef cattle. Whole blood DNA was extracted and tested for presence of Anaplasma spp. and Ehrlichia ruminantium DNA through amplification of the 16S rRNA and map1 genes. Positive samples to Anaplasma spp. were subject to PCR assay targeting the A. marginale-msp5 gene. Amplicons obtained were purified, sequenced and subject to phylogenetic analyses. RESULTS Anaplasma spp., A. marginale and E. ruminantium were detected in 153 (76.5%), 142 (71%) and 19 (9.5%) of all the samples analyzed, respectively. On this same sample group, 19 (9.5%) were co-infected with A. marginale and E. ruminantium. The 16S rRNA sequences of Anaplasma spp. obtained were phylogenetically related to A. marginale, A. centrale and A. platys. Phylogenetic analysis revealed that A. marginale-msp5 nucleotide sequences were grouped with sequences from Asia, Africa and Latin America, whereas E. ruminantium-map1 DNA nucleotide sequences were positioned in multiple clusters. CONCLUSION Cattle in Maputo Province are reservoirs for multiple Anaplasma species. A high positivity rate of infection by A. marginale was observed, as well as high genetic diversity of E. ruminantium. Furthermore, five new genotypes of E. ruminantium-map1 were identified.
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Affiliation(s)
- Carlos António Matos
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique.
| | | | | | - Aida Cristina Cala
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique
| | - Carlos Francisco Sitoe
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique
| | - Ana Paula Rúpia Vinte
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique
| | - Cristovão Mario Mondlane
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique
| | - Marcos Rogério André
- Vector-Borne Bioagents Laboratory (VBBL), Departamento de Patologia, Reprodução e Saúde Única, São Paulo State University (UNESP), School of Agricultural and Veterinary Sciences, Jaboticabal, Jaboticabal, SP, Brasil
| | - Maria do Carmo Carrilho
- Laboratório de Parasitologia, Direcção de Ciências Animais, Avenida de Moçambique, km 1.5, Bairro do Jardim, Cidade de Maputo, C.P. 1922 , Moçambique
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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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Mnisi SS, Mphuthi MBN, Ramatla T, Mofokeng LS, Thekisoe O, Syakalima M. Molecular Detection and Genetic Characterization of Ehrlichia ruminantium Harbored by Amblyomma hebraeum Ticks of Domestic Ruminants in North West Province, South Africa. Animals (Basel) 2022; 12:ani12192511. [PMID: 36230251 PMCID: PMC9559644 DOI: 10.3390/ani12192511] [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: 06/13/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022] Open
Abstract
Ehrlichia ruminantium (E. ruminantium) is the causative agent of heartwater disease and it is mainly transmitted to livestock by Amblyomma hebraeum (A. hebraeum) tick in South Africa. This study investigated the occurrence of E. ruminantium and its genetic diversity in ticks within Ngaka Modiri Molema district of North West Province in South Africa. Genomic DNA was extracted from whole A. hebraeum ticks totaling 876 and resulted in a total of 292 pooled DNA samples. Firstly, conventional PCR was used to detect Ehrlichia spp. targeting the dsbA gene, followed by nested PCR targeting the Map1 gene performed on DNA pool samples that were positive from the first PCR. One hundred and six tick DNA pool samples were positive by dsbA gene PCR for the presence of Ehrlichia spp. with minimum infection rate (MIR) of 121, while 13/106 were positive by Map1 PCR with MIR of 15. Different E. ruminantium Map1 genotypes (NWUe1, NWUe2, NWUe3, NWUe5, and NWUe6) were detected from tick samples and were closely related to more than 13 gene sequences of E. ruminantium from the NCBI GenBank database. These findings suggest that there is a significant diversity of E. ruminantium infecting ticks in the study area.
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Affiliation(s)
- Sifiso S. Mnisi
- Department of Animal Health, School of Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
| | - Malekoba B. N. Mphuthi
- Department of Animal Health, School of Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
| | - Tsepo Ramatla
- Unit for Environmental Sciences and Management, North-West University, Private Bag X6001, Potchefstroom 2531, South Africa
- Correspondence: ; Tel.: +27-18-299-2521
| | - Lehlohonolo S. Mofokeng
- Unit for Environmental Sciences and Management, North-West University, Private Bag X6001, Potchefstroom 2531, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North-West University, Private Bag X6001, Potchefstroom 2531, South Africa
| | - Michelo Syakalima
- Department of Animal Health, School of Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
- Disease Control Department, School of Veterinary Medicine, University of Zambia, Lusaka P.O. Box 32379, Zambia
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Tawana M, Onyiche TE, Ramatla T, Mtshali S, Thekisoe O. Epidemiology of Ticks and Tick-Borne Pathogens in Domestic Ruminants across Southern African Development Community (SADC) Region from 1980 until 2021: A Systematic Review and Meta-Analysis. Pathogens 2022; 11:pathogens11080929. [PMID: 36015049 PMCID: PMC9414594 DOI: 10.3390/pathogens11080929] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/14/2022] [Accepted: 04/15/2022] [Indexed: 11/16/2022] Open
Abstract
Ticks are hematophagous ectoparasites that are capable of infesting a wide range of mammals, including domestic animals, ruminants, wildlife, and humans across the world, and they transmit disease-causing pathogens. Numerous individual epidemiological studies have been conducted on the distribution and prevalence of ticks and tick-borne diseases (TBDs) in the Southern African Developing Community (SADC) region, but no effort has been undertaken to synchronize findings, which would be helpful in the implementation of consolidated tick control measures. With the aim of generating consolidated pooled prevalence estimates of ticks and TBDs in the SADC region, we performed a systematic review and meta-analysis of published articles using the PRISMA 2020 guidelines. A deep search was performed on five electronic databases, namely, PubMed, ScienceDirect, Google Scholar, AJOL, and Springer Link. Of the 347 articles identified, only 61 of the articles were eligible for inclusion. In total, 18,355 tick specimens were collected, belonging to the genera Amblyomma, Haemaphysalis, Hyalomma, and Rhipicephalus (including Boophilus) across several countries, including South Africa (n = 8), Tanzania (n = 3), Zambia (n = 2), Zimbabwe (n = 2), Madagascar (n = 2), Angola (n = 2), Mozambique (n = 1), and Comoros (n = 1). The overall pooled prevalence estimate (PPE) of TBPs in livestock was 52.2%, with the highest PPE in cattle [51.2%], followed by sheep [45.4%], and goats [29.9%]. For bacteria-like and rickettsial TBPs, Anaplasma marginale had the highest PPE of 45.9%, followed by A. centrale [14.7%], A. phagocytophilum [2.52%], and A. bovis [0.88%], whilst Ehrlichia ruminantium had a PPE of 4.2%. For piroplasmids, Babesia bigemina and B. bovis had PPEs of 20.8% and 20.3%, respectively. Theileria velifera had the highest PPE of 43.0%, followed by T. mutans [29.1%], T. parva [25.0%], and other Theileria spp. [14.06%]. Findings from this study suggest the need for a consolidated scientific approach in the investigation of ticks, TBPs, and TBDs in the whole SADC region, as most of the TBDs are transboundary and require a regional control strategy.
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Affiliation(s)
- Mpho Tawana
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - ThankGod E. Onyiche
- Department of Veterinary Parasitology and Entomology, University of Maiduguri, Maiduguri 600230, Nigeria
| | - Tsepo Ramatla
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
- Correspondence: ; Tel.: +27-18-299-2521
| | - Sibusiso Mtshali
- Foundational Research and Services, South African National Biodiversity Institute, National Zoological Gardens, Pretoria 0001, South Africa
- University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
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Basit MA, Ijaz M, Khan JA, Ashraf K, Abbas RZ. Molecular Evidence and Hematological Profile of Bovines Naturally Infected with Ehrlichiosis in Southern Punjab, Pakistan. Acta Parasitol 2022; 67:72-78. [PMID: 34138414 DOI: 10.1007/s11686-021-00433-0] [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: 12/26/2020] [Accepted: 06/01/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE Ehrlichiosis is one of the tick-borne diseases, which is not only neglected in Pakistan but only a few reports have been documented throughout the globe. The purpose of this study is to highlight and report the neglected pathogen from bovines in Pakistan. METHODS In this study, the pathogen was detected initially based on microscopy, followed by the molecular confirmation and phylogenetic analysis of the pathogen from bovines from south Punjab, Pakistan. The hematological parameters were also assessed in Ehrlichia positive and negative animals. The information of different disease determinants was analyzed by a logistic regression model on SPSS. RESULTS The study has reported an 11.98% (23/192) prevalence of Ehrlichiosis from bovines. The prevalence was slightly more in cattle (13.5%) as compared to the buffaloes (10.4%). The previous tick's history and tick control methods were proved to be the key factors with the occurrence of the disease. The isolates from Pakistan Ehrlichia spp. Pakistan/31, 36, and 8 clustered with the isolates from the USA, Nicaraguan, France, South Africa, and Uganda. Platelet count, hemoglobin level, and hematocrit were found significantly decreased in Ehrlichia affected animals when compared to the healthy bovines. CONCLUSION This is the first report of ehrlichiosis from bovines in Pakistan and will provide the roadmap for future research.
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Campbell Z, Coleman P, Guest A, Kushwaha P, Ramuthivheli T, Osebe T, Perry B, Salt J. Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys. Prev Vet Med 2021; 189:105279. [PMID: 33581421 PMCID: PMC8024747 DOI: 10.1016/j.prevetmed.2021.105279] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/18/2020] [Accepted: 01/18/2021] [Indexed: 12/15/2022]
Abstract
Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.
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Affiliation(s)
- Zoë Campbell
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya.
| | - Paul Coleman
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Andrea Guest
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Peetambar Kushwaha
- GALVmed Asia Office, Unit 118 & 120 B, Splendor Forum, Plot No 3, Jasola District Centre, Jasola, New Delhi, 110025, India
| | - Thembinkosi Ramuthivheli
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Tom Osebe
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Brian Perry
- Nuffield College of Clinical Medicine, University of Oxford, United Kingdom; College of Medicine and Veterinary Medicine, University of Edinburgh, Arthurstone House, Meigle, Blairgowrie, PH12 8QW, Scotland, United Kingdom
| | - Jeremy Salt
- GALVmed UK Office, Doherty Building, Pentlands Science Park, Bush Loan, Penicuik Edinburgh, EH26 0PZ, Scotland, United Kingdom
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Nguyen AHL, Tiawsirisup S, Kaewthamasorn M. Molecular detection and genetic characterization of Anaplasma marginale and Anaplasma platys-like (Rickettsiales: Anaplasmataceae) in water buffalo from eight provinces of Thailand. BMC Vet Res 2020; 16:380. [PMID: 33032591 PMCID: PMC7542745 DOI: 10.1186/s12917-020-02585-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 09/20/2020] [Indexed: 12/26/2022] Open
Abstract
Background Anaplasmosis, an animal disease caused by rickettsial bacteria in the genus Anaplasma, is of considerable economic importance in livestock animals in many countries worldwide. The objectives of this study were to determine the identity, prevalence, and geographic distribution of Ehrlichia and Anaplasma in naturally infected water buffalo in Thailand using PCR amplification and sequencing of the 16S ribosomal RNA and heat shock protein groEL genes. A total of 456 buffalo blood samples from Thailand were investigated. Species identification and genetic differentiation of intra-population and inter-population with the global isolates were conducted based on nucleotide sequences. Interplay between the infection and host factors was also assessed. Results Overall, 41% of water buffalo were found to be infected with rickettsial organisms in the family Anaplasmataceae, but Ehrlichia spp., Neorickettsia spp., and Wolbachia spp. were not found in any of the sequenced samples in this study. Female buffalo were more frequently infected with bacteria in the family Anaplasmataceae than males [71 out of 176 females (40.3%) versus 11 out of 47 males (23.4%)]. The Odds Ratio value indicated that the risk of infection for female buffalo was 2.2-fold higher than that for males (p < 0.05). We detected three haplotypes of A. marginale 16S rRNA gene and they were placed in a clade that was closely related to the A. marginale in buffalo in China; and cattle in Thailand, Uganda, and China. Homology searching of groEL sequences against the GenBank™ database using the BLASTn algorithm revealed that the obtained sequences had a high percentage similarity (98.36–99.62%) to A. platys sequences. The groEL sequences of three A. platys-like isolates were clustered in the same clade as the A. platys from the tick Rhipicephalus microplus in China. Conclusions Our data showed that the apparently healthy buffalo were naturally infected by bacteria in the family Anaplasmataceae at a relatively high prevalence. We also report the finding of A. platys-like infections in water buffalo in Thailand for the first time. Water buffalo serving as the reservoir host of anaplasmosis is of concern for managing the disease control and prevention in ruminants.
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Affiliation(s)
- Anh H L Nguyen
- The international graduate course of Veterinary Science and Technology (VST), Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.,Veterinary Parasitology Research Group, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Sonthaya Tiawsirisup
- Animal Vector-Borne Disease Research Unit, The Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Morakot Kaewthamasorn
- Veterinary Parasitology Research Group, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand. .,Animal Vector-Borne Disease Research Unit, The Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
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Peter SG, Gakuya DW, Maingi N, Mulei CM. Prevalence and risk factors associated with Ehrlichia infections in smallholder dairy cattle in Nairobi City County, Kenya. Vet World 2019; 12:1599-1607. [PMID: 31849422 PMCID: PMC6868257 DOI: 10.14202/vetworld.2019.1599-1607] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/03/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND AND AIM Ehrlichiosis caused by Ehrlichia ruminantium is a tick-borne disease of great economic importance in cattle production worldwide. Despite its economic impact, limited knowledge is available on its epidemiology in Africa, including Kenya. Suspected cases of E. ruminantium infections have been reported in the recent past to the University of Nairobi's Veterinary Hospital, prompting the need to investigate their possible re-emergence. Therefore, this study was aimed at determining the prevalence of E. ruminantium among smallholder dairy cattle in Nairobi City County and to assess potential risk factors. This knowledge may guide the development of appropriate control strategies of ehrlichiosis, subsequently reducing associated losses. MATERIALS AND METHODS A total of 107 smallholder dairy farms from Nairobi City County were recruited for the study. Blood samples were collected from 314 apparently healthy dairy cattle, and Giemsa-stained blood smears were screened under the microscope for Ehrlichia species. A commercial antigen enzyme-linked immunosorbent assay (ELISA) kit was then used to confirm the presence of the infections in serum samples. A pre-tested questionnaire was used to collect data on management practices that may be potential risk factors. A univariate and mixed-effects logistic regression was then used to determine significant risk factors. RESULTS On microscopy, 79.3% (249/314) of the sampled animals had Ehrlichia-like inclusion bodies in white blood cells, though only 18.6% (95% confidence interval [CI] 14.2-23.0) of these were confirmed to be E. ruminantium on ELISA. A farm-level prevalence of 35.5% (95% CI 27.0-45.3) was reported. Female-headed households (p=0.013), farms in Langata region (p=0.027), cleaning of cowsheds fortnightly (p=0.019), and roofing of cowshed (p=0.022) were factors significantly associated with E. ruminantium infections. CONCLUSION There is a relatively high prevalence of E. ruminantium infections in apparently healthy cattle in smallholder dairy farms in this area, warranting control measures. It is critical to improve animal welfare-related factors, such as cowshed cleaning and roofing, as well as the strategic location of farms, especially, since reservoirs may reduce infection levels in the farms, in relation to wildlife. However, since Ehrlichia-like inclusion bodies other than those of E. ruminantium were observed in this study, there is a need to investigate further these factors and the possibility of other Ehrlichia species infecting cattle in the study area.
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Affiliation(s)
- Shepelo Getrude Peter
- Department of Clinical Studies, Faculty of Veterinary Medicine, University of Nairobi, Kenya
| | - Daniel Waweru Gakuya
- Department of Clinical Studies, Faculty of Veterinary Medicine, University of Nairobi, Kenya
| | - Ndichu Maingi
- Department of Veterinary Pathology, Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Nairobi, Kenya
| | - Charles Matiku Mulei
- Department of Clinical Studies, Faculty of Veterinary Medicine, University of Nairobi, Kenya
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