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Evans A, Madder M, Fourie J, Halos L, Kumsa B, Kimbita E, Byaruhanga J, Mwiine FN, Muhanguzi D, Adehan SB, Toure A, Nzalawahe J, Aboagye-Antwi F, Ogo NI, Meyer L, Jongejan F, Cheikhi IB, Fisher M, Holdsworth P. Acaricide resistance status of livestock ticks from East and West Africa and in vivo efficacy of acaricides to control them. Int J Parasitol Drugs Drug Resist 2024; 25:100541. [PMID: 38761529 PMCID: PMC11133915 DOI: 10.1016/j.ijpddr.2024.100541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 05/20/2024]
Abstract
Through a collaborative effort across six Sub-Saharan African countries, using recognized international assessment techniques, 23 stocks of three tick species (Rhipicephalus microplus, Rhipicephalus appendiculatus and Amblyomma variegatum) of economic importance for rural small holder farming communities from East and West Africa were collected from cattle, and evaluated in in vitro larval packet tests (LPT). The results demonstrated medium to high resistance to chlorfenvinphos and amitraz across species. Rhipicephalus microplus demonstrated high level alpha-cypermethrin and cypermethrin resistance. Stocks of A. variegatum (West Africa) and R. appendiculatus (Uganda) demonstrated medium level ivermectin resistance. The four least susceptible stocks (East and West African R. microplus, A. variegatum and R. appendiculatus) were taken into in vivo controlled cattle studies where fipronil was found effective against West and East African R. microplus isolates although persistent efficacy failed to reach 90%. Cymiazole and cypermethrin, and ivermectin based acaricides were partially effective against R. microplus without persistent efficacy. Flumethrin spray-on killed A. variegatum within 72 h for up to 10 days posttreatment, however product application was directly to tick attachment sites, which may be impractical under field conditions. A flumethrin pour-on formulation on goats provided persistent efficacy against A. variegatum for up to one-month. Therapeutic control was achieved against R. appendiculatus through weekly spraying cattle with flumethrin, amitraz or combined cymiazole and cypermethrin. A fipronil pour-on product offered four-week residual control against R. appendiculatus (with slow onset of action). Few studies have assessed and directly compared acaricidal activity in vitro and in vivo. There was some discordance between efficacy indicated by LPT and in vivo results. This observation calls for more research into accurate and affordable assessment methods for acaricide resistance. No single active or product was effective against all three tick species, emphasising the need for the development of alternative integrated tick management solutions.
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Affiliation(s)
- Alec Evans
- Clinglobal, B03/04, The Tamarin Commercial Hub, Jacaranda Avenue, Tamarin, 90903, Mauritius.
| | - Maxime Madder
- Clinglobal, B03/04, The Tamarin Commercial Hub, Jacaranda Avenue, Tamarin, 90903, Mauritius.
| | - Josephus Fourie
- Clinvet USA, 1479 Talmadge Hill South, Waverly, NY, 14892, USA.
| | - Lénaïg Halos
- Bill & Melinda Gates Foundation, Seattle, WA, USA.
| | - Bersissa Kumsa
- Department of Parasitology, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Ethiopia.
| | - Elikira Kimbita
- Department of Veterinary Microbiology and Parasitology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, PO Box 3019, Morogoro, Tanzania.
| | - Joseph Byaruhanga
- Department of Bio-molecular Resources and Bio-laboratory Sciences (BBS), College of Veterinary Medicine, Makerere University, Kampala, Uganda.
| | - Frank Norbert Mwiine
- Department of Bio-molecular Resources and Bio-laboratory Sciences (BBS), College of Veterinary Medicine, Makerere University, Kampala, Uganda.
| | - Dennis Muhanguzi
- Department of Bio-molecular Resources and Bio-laboratory Sciences (BBS), College of Veterinary Medicine, Makerere University, Kampala, Uganda.
| | - Safiou Bienvenu Adehan
- National Institute of Agricultural Research (INRAB), Animal and Fisheries Health and Nutrition Support Laboratory (LASNAH), 01 BP 884, Cotonou, Benin.
| | - Alassane Toure
- Université Nangui Abrogoua, UFR Sciences de la Nature, 02 Bp 801 Abidjan 02, Côte d'Ivoire, Nigeria.
| | - Jahashi Nzalawahe
- Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania.
| | - Fred Aboagye-Antwi
- Department of Animal Biology and Conservation Science, School of Biological Sciences, College of Basic and Applied Sciences, University of Ghana, Legon-Accra, Ghana.
| | - Ndudim Isaac Ogo
- National Veterinary Research Institute, Vom, Plateau State, Nigeria.
| | - Leon Meyer
- Clinvet S.A., Douar Dbabej, Beni Yekhlef B.P 301, CP 28815, Mohammedia, Morocco.
| | - Frans Jongejan
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, 0110, South Africa.
| | | | - Maggie Fisher
- Veterinary Research Management Limited, Shernacre Cottage, Lower Howsell Road, Malvern, WR141UX, Worcestershire, United Kingdom.
| | - Peter Holdsworth
- PAH Consultancy Pty Ltd, 3/27 Gaunson Crescent, Wanniassa, Canberra, ACT, 2903, Australia.
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Monakale KS, Ledwaba MB, Smith RM, Gaorekwe RM, Malatji DP. A systematic review of ticks and tick-borne pathogens of cattle reared by smallholder farmers in South Africa. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2024; 6:100205. [PMID: 39258000 PMCID: PMC11386001 DOI: 10.1016/j.crpvbd.2024.100205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 07/24/2024] [Accepted: 07/26/2024] [Indexed: 09/12/2024]
Abstract
Ticks are important ectoparasites of domestic animals, wild animals and humans. They spread a variety of infective agents such as protozoans, viruses, and bacteria. Cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens due to the type of production system practiced by the farmers. Hence, this review was focused on the occurrence of ticks and tick-borne pathogens in cattle reared by smallholder farmers in South Africa. The systematic search produced a total of 13,408 articles from four databases, and after screening processes, the review utilized 23 articles published between 1983 and 2023. A total of 26 tick species belonging to seven genera were identified in the reviewed articles, with Rhipicephalus (Boophilus) decoloratus and Rhipicephalus evertsi evertsi being the most frequently reported tick species in South Africa followed by Amblyomma hebreum, Rhipicephalus appendiculatus, Hyalomma marginatum rufipes, Rhipicephalus microplus, Rhipicephalus follis, Rhipicephalus gertrudae and Hyalomma truncatum. The most frequently reported tick-borne pathogens across the provinces included Babesia bigemina, Babesia bovis, and Anaplasma marginale, with Eastern Cape Province accounting for most of the records followed by KwaZulu-Natal and Mpumalanga Provinces. The findings of this review confirm that cattle reared by smallholder farmers harbour various ticks and tick-borne pathogens of veterinary, public health and economic importance, and regular monitoring of tick infestations in South Africa is recommended to avoid disease outbreaks.
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Affiliation(s)
- Katleho Sechaba Monakale
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Science, University of South Africa, South Africa
| | - Maphuthi Betty Ledwaba
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Science, University of South Africa, South Africa
| | - Rae Marvin Smith
- Department of Life and Consumer Science, College of Agriculture and Environmental Science, University of South Africa, South Africa
| | - Realeboga Masego Gaorekwe
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Science, University of South Africa, South Africa
| | - Dikeledi Petunia Malatji
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Science, University of South Africa, South Africa
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3
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Meiring C, Labuschagne M. Using QUASR-PCR as a field-based genotyping assay for a tick acaricide resistance marker. Sci Rep 2024; 14:13584. [PMID: 38866908 PMCID: PMC11169234 DOI: 10.1038/s41598-024-64401-0] [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: 03/22/2024] [Accepted: 06/07/2024] [Indexed: 06/14/2024] Open
Abstract
A novel, turnkey, field-based workflow was developed and validated using Rhipicephalus microplus DNA as a template to detect the presence of the voltage-gated sodium channel kdr mutation. The field-based compatible workflow comprises manual sample homogenization for DNA extraction, PCR amplification of the targets in a closed tube, and end-point detection of the PCR products. An R. microplus species-specific assay was also included to confirm species identity and ensure the validity of the kdr mutation assay. The assays were sensitive and specific to the targets, and the workflow resulted in a turnaround time of approximately 1 h at a low cost. The novel combination of PCR with closed-tube and end-point fluorescent detection allows for easy conversion of existing conventional lab-based PCR assays into field-based detection assays. The incorporation of custom-designed 3D-printed components in the workflow provides easy adaptability and modification of the components for diverse nucleic acid detection workflows.
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Affiliation(s)
- Christina Meiring
- , Clinglobal, B03/04, The Tamarin Commercial Hub, Jacaranda Avenue, Tamarin, 90903, Mauritius
- , Clinomics, Uitzich Road, Bainsvlei, Bloemfontein, 9338, South Africa
| | - Michel Labuschagne
- , Clinglobal, B03/04, The Tamarin Commercial Hub, Jacaranda Avenue, Tamarin, 90903, Mauritius.
- , Clinomics, Uitzich Road, Bainsvlei, Bloemfontein, 9338, South Africa.
- Department of Microbiology and Biochemistry, Faculty: Natural and Agricultural Sciences, PO Box 339, Bloemfontein, 9300, Republic of South Africa.
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Noh SM, Ujczo J, Alperin DC, Jarvis SM, Solyman MSM, Koku R, Akinsulie OC, Hoffmann EE. Identification of Anaplasma marginale adhesins for entry into Dermacentor andersoni tick cells using phage display. Infect Immun 2024; 92:e0054023. [PMID: 38727242 PMCID: PMC11237752 DOI: 10.1128/iai.00540-23] [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: 12/24/2023] [Accepted: 04/15/2024] [Indexed: 06/12/2024] Open
Abstract
Anaplasma marginale is an obligate, intracellular, tick-borne bacterial pathogen that causes bovine anaplasmosis, an often severe, production-limiting disease of cattle found worldwide. Methods to control this disease are lacking, in large part due to major knowledge gaps in our understanding of the molecular underpinnings of basic host-pathogen interactions. For example, the surface proteins that serve as adhesins and, thus, likely play a role in pathogen entry into tick cells are largely unknown. To address this knowledge gap, we developed a phage display library and screened 66 A. marginale proteins for their ability to adhere to Dermacentor andersoni tick cells. From this screen, 17 candidate adhesins were identified, including OmpA and multiple members of the Msp1 family, including Msp1b, Mlp3, and Mlp4. We then measured the transcript of ompA and all members of the msp1 gene family through time, and determined that msp1b, mlp2, and mlp4 have increased transcript during tick cell infection, suggesting a possible role in host cell binding or entry. Finally, Msp1a, Msp1b, Mlp3, and OmpA were expressed as recombinant protein. When added to cultured tick cells prior to A. marginale infection, all proteins except the C-terminus of Msp1a reduced A. marginale entry by 2.2- to 4.7-fold. Except OmpA, these adhesins lack orthologs in related pathogens of humans and animals, including Anaplasma phagocytophilum and the Ehrlichia spp., thus limiting their utility in a universal tick transmission-blocking vaccine. However, this work greatly advances efforts toward developing methods to control bovine anaplasmosis and, thus, may help improve global food security.
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Affiliation(s)
- Susan M. Noh
- Animal Disease Research Unit, United States Department of Agriculture, Agricultural Research Service, Pullman, Washington, USA
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Jessica Ujczo
- Animal Disease Research Unit, United States Department of Agriculture, Agricultural Research Service, Pullman, Washington, USA
| | - Debra C. Alperin
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Shelby M. Jarvis
- Animal Disease Research Unit, United States Department of Agriculture, Agricultural Research Service, Pullman, Washington, USA
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Muna S. M. Solyman
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Roberta Koku
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Olalekan C. Akinsulie
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
| | - Elizabeth E. Hoffmann
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, USA
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de la Fuente J, Ghosh S. Evolution of tick vaccinology. Parasitology 2024:1-8. [PMID: 38586999 DOI: 10.1017/s003118202400043x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Ticks represent a major concern for society worldwide. Ticks are also difficult to control, and vaccines represent the most efficacious, safe, economically feasible and environmentally sustainable intervention. The evolution of tick vaccinology has been driven by multiple challenges such as (1) Ticks are difficult to control, (2) Vaccines control tick infestations by reducing ectoparasite fitness and reproduction, (3) Vaccine efficacy against multiple tick species, (4) Impact of tick strain genetic diversity on vaccine efficacy, (5) Antigen combination to improve vaccine efficacy, (6) Vaccine formulations and delivery platforms and (7) Combination of vaccines with transgenesis and paratransgenesis. Tick vaccine antigens evolved from organ protein extracts to recombinant proteins to chimera designed by vaccinomics and quantum vaccinomics. Future directions will advance in these areas together with other novel technologies such as multiomics, AI and Big Data, mRNA vaccines, microbiota-driven probiotics and vaccines, and combination of vaccines with other interventions in collaboration with regions with high incidence of tick infestations and tick-borne diseases for a personalized medicine approach.
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Affiliation(s)
- José de la Fuente
- SaBio. Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM, Ronda de Toledo 12, 13005 Ciudad Real, Spain
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA
| | - Srikant Ghosh
- Entomology Laboratory, Parasitology Division, ICAR-Indian Veterinary Research Institute, Izatnagar 243122, Bareilly, UP, India
- Eastern Regional Station- Indian Veterinary Research Institute, 37 Belgachia Road, Kolkata-700037, West Bengal, India
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Leal LLLL, Ferreira LL, de Morais IML, Salvador VF, Trindade ASN, Pereira Neto O, Soares VE, de Almeida Borges F, Monteiro CMDO, Lopes WDZ. What is the optimal timing to initiate strategic control of Rhipicephalus microplus in taurine cattle in a tropical region? EXPERIMENTAL & APPLIED ACAROLOGY 2024; 92:217-232. [PMID: 38329588 DOI: 10.1007/s10493-023-00877-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 12/26/2023] [Indexed: 02/09/2024]
Abstract
Cattle tick control poses a significant challenge for livestock in tropical and subtropical regions. The objective of this study was to determine the most suitable timing to initiate a strategic tick control program and to identify the ideal number of acaricide treatments for adult taurine cattle (Bos taurus taurus) in a tropical region throughout the year. Three groups with 10 bovines each were performed: T01 (strategic treatment in late autumn/winter/late spring, every 28 days), T02 (strategic treatment to act in the "first tick generation" - early spring/summer/early autumn, every 28 days) and T03 (control). Tick counts (females 4-8 mm) were conducted every 14 days. If the tick burden in any group reached 30 or more during these counts, we applied an additional treatment. Over the course of a year, T02 required significantly fewer (p < 0.05) acaricide treatments than T01, with nine treatments for T02 and eleven for T01. Furthermore, during the tick counts, animals in T02 showed a lower tick burden compared to those in T01. Initiating the strategic tick control program in early spring, corresponding to the first tick generation, proved more effective than starting in autumn. This approach not only required fewer acaricide treatments but also resulted in a reduced tick burden. These benefits are particularly valuable in terms of animal welfare and managing acaricide resistance issues.
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Affiliation(s)
- Luccas Lourenzzo Lima Lins Leal
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Lorena Lopes Ferreira
- Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Igor Maciel Lopes de Morais
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Vanessa Ferreira Salvador
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Artur Siqueira Nunes Trindade
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | | | | | - Fernando de Almeida Borges
- Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | - Caio Marcio de Oliveira Monteiro
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
- Departamento de Biociências e Tecnologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Welber Daniel Zanetti Lopes
- Centro de Parasitologia Veterinária, Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
- Departamento de Biociências e Tecnologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
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7
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Ngetich C, Kamau L, Simbauni J, Mwendia C, Owido M, Kiio I, Matika O, Foster S, Birkett M, Djikeng A, Watson KA, Githaka N. The potential for use of haematological and anti-IgE humoral responses as phenotypic markers for tick resistance in cattle. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2023; 5:100159. [PMID: 38179546 PMCID: PMC10764256 DOI: 10.1016/j.crpvbd.2023.100159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 11/08/2023] [Accepted: 11/23/2023] [Indexed: 01/06/2024]
Abstract
Approximately 80% of the global cattle population is at risk of infestation and infection by ticks and tick-borne diseases (TTBDs). The economic losses from animal mortality, reduced production, vector control costs and animal treatment are very substantial, hence there is an urgent need to develop and deploy alternative vector control strategies. Breeding for host tick resistance has the potential for sustainable large-scale TTBD control especially in cattle. The gold standard method for phenotyping tick resistance in cattle is by counting ticks on the body but is very laborious and subjective. Better methods for phenotyping tick resistance more objectively, faster and at scale, are essential for selecting host genetic resistance to ticks. This study investigated the correlation between haematological cellular profiles and immunological responses (immunoglobulin E, IgE) and full body tick counts in herds of Bos indicus and Bos taurus following artificial tick challenge with Rhipicephalus decoloratus larvae. Fifty-four Friesian and Ayrshire (Bos taurus) and 52 East African Zebu (Bos indicus) calves were each infested with ∼2500 larvae. Near-replete adult female ticks (≥ 4.5 mm) were counted daily from Day 20-25. Blood and serum samples were obtained from each animal on Days 0 and 23 for cellular blood and IgE titre analysis, respectively. The indicine cattle were refractory to R. decoloratus infestation in comparison with the taurine breed (P < 0.0001). Repeated measurements of blood components pre-infestation revealed a significant (P < 0.05) association with tick count in IgE and red blood cells, haematocrit, and haemoglobin post-infestation. There was also a strong positive correlation between the tick counts and red blood cell numbers, haemoglobin, haematocrit, and IgE concentration (P < 0.0001) following tick challenge. The application of this approach to phenotype host resistance needs to be assessed using higher cattle numbers and with different tick species or genera.
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Affiliation(s)
- Collins Ngetich
- International Livestock Research Institute (ILRI), PO Box 30709, Nairobi 00100, Kenya
- Zoological Sciences and Animal Sciences Department, Kenyatta University, P.O. Box 43844, Nairobi 00100, Kenya
| | - Lucy Kamau
- Zoological Sciences and Animal Sciences Department, Kenyatta University, P.O. Box 43844, Nairobi 00100, Kenya
| | - Jemimah Simbauni
- Zoological Sciences and Animal Sciences Department, Kenyatta University, P.O. Box 43844, Nairobi 00100, Kenya
| | - Charles Mwendia
- Biochemistry and Molecular Biology Department, Egerton University, P.O. Box 536-20115, Egerton, Kenya
| | - Milton Owido
- International Livestock Research Institute (ILRI), PO Box 30709, Nairobi 00100, Kenya
| | - Irene Kiio
- International Livestock Research Institute (ILRI), PO Box 30709, Nairobi 00100, Kenya
| | - Oswald Matika
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush Campus, EH25 9RG, UK
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, EH25 9RG, UK
| | - Sarah Foster
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Michael Birkett
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Appolinaire Djikeng
- International Livestock Research Institute (ILRI), PO Box 30709, Nairobi 00100, Kenya
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, EH25 9RG, UK
| | - Kellie Anne Watson
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush Campus, EH25 9RG, UK
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, EH25 9RG, UK
| | - Naftaly Githaka
- International Livestock Research Institute (ILRI), PO Box 30709, Nairobi 00100, Kenya
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Riggio V, Madder M, Labuschagne M, Callaby R, Zhao R, Djikeng A, Fourie J, Prendergast JGD, Morrison LJ. Meta-analysis of heritability estimates and genome-wide association for tick-borne haemoparasites in African cattle. Front Genet 2023; 14:1197160. [PMID: 37576560 PMCID: PMC10417722 DOI: 10.3389/fgene.2023.1197160] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 07/05/2023] [Indexed: 08/15/2023] Open
Abstract
The control of tick-borne haemoparasites in cattle largely relies on the use of acaricide drugs against the tick vectors, with some vaccination also being used against selected pathogens. These interventions can be difficult in Africa, where accessibility and cost of vaccines can be issues, and the increasing resistance of tick vectors to the widely used acaricides is a complication to disease control. A potential complementary control strategy could be the exploitation of any natural host genetic resistance to the pathogens. However, there are currently very few estimates of the extent of host resistance to tick-borne haemoparasites, and a significant contributing factor to this knowledge gap is likely to be the difficulty of collecting appropriate samples and data in the smallholder systems that predominate livestock production in low- and middle-income countries, particularly at scale. In this study, we have estimated the heritability for the presence/absence of several important haemoparasite species (including Anaplasma marginale, Babesia bigemina, Babesia bovis, and Ehrlichia ruminantium), as well as for relevant traits such as body weight and body condition score (BCS), in 1,694 cattle from four African countries (Burkina Faso, Ghana, Nigeria, and Tanzania). Heritability estimates within countries were mostly not significant, ranging from 0.05 to 0.84 across traits and countries, with standard errors between 0.07 and 0.91. However, the weighted mean of heritability estimates was moderate and significant for body weight and BCS (0.40 and 0.49, respectively), with significant heritabilities also observed for the presence of A. marginale (0.16) and E. ruminantium (0.19). In a meta-analysis of genome-wide association studies (GWAS) for these traits, two peaks were identified as reaching the suggestive significance threshold (p < 1.91 × 10-7 and p < 1.89 × 10-7, respectively): one on chromosome 24 for BCS and one on chromosome 8 for the E. ruminantium infection status. These findings indicate that there is likely to be a genetic basis that contributes to pathogen presence/absence for tick-borne haemoparasite species, which could potentially be exploited to improve cattle resistance in Africa to the economically important diseases caused by these pathogens.
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Affiliation(s)
- Valentina Riggio
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | | | | | - Rebecca Callaby
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Rongrong Zhao
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Appolinaire Djikeng
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | | | - James G. D. Prendergast
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Liam J. Morrison
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
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9
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Bishop RP, Githaka NW, Bazarusanga T, Bhushan C, Biguezoton A, Vudriko P, Muhanguzi D, Tumwebaze M, Bosco TJ, Shacklock C, Kiama J, Madder M, Maritz-Olivier C, Zhao W, Maree F, Majekodunmi AO, Halos L, Jongejan F, Evans A. Control of ticks and tick-borne diseases in Africa through improved diagnosis and utilisation of data on acaricide resistance. Parasit Vectors 2023; 16:224. [PMID: 37415211 DOI: 10.1186/s13071-023-05803-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/08/2023] [Indexed: 07/08/2023] Open
Abstract
A meeting, sponsored by the Bill and Melinda Gates Foundation (BMGF) and organised by Clinglobal, was held at The International Livestock Research Institute (ILRI) in Nairobi, Kenya, from 19th - to 21st October 2022. The meeting assembled a unique group of experts on tick control in Africa. Academia, international agencies (FAO and ILRI), the private Animal Health sector and government veterinary services were represented. The significant outcomes included: (i) a shared commitment to standardisation and improvement of acaricide resistance bioassay protocols, particularly the widely used larval packet test (LPT); (ii) development of novel molecular assays for detecting acaricide resistance; (3) creation of platforms for disseminating acaricide resistance data to farmers, veterinary service providers and veterinary authorities to enable more rational evidence-based control of livestock ticks. Implementation of enhanced control will be facilitated by several recently established networks focused on control of parasites in Africa and globally, whose activities were presented at the meeting. These include a newly launched community of practice on management of livestock ticks, coordinated by FAO, an African module of the World Association for the Advancement of Veterinary Parasitology (WAAVP-AN) and the MAHABA (Managing Animal Health and Acaricides for a Better Africa) initiative of Elanco Animal Health.
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Affiliation(s)
| | | | | | | | | | - Patrick Vudriko
- Research Centre for Tropical Diseases and Vector Control (RTC) Makerere University, Kampala, Uganda
| | - Dennis Muhanguzi
- Molecular and Computational Biology Research Group, Makerere University, Kampala, Uganda
| | - Maria Tumwebaze
- Research Centre for Tropical Diseases and Vector Control (RTC) Makerere University, Kampala, Uganda
| | | | | | | | | | - Christine Maritz-Olivier
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Weining Zhao
- United Nations Food and Agriculture Organisation, Rome, Italy
| | | | - Ayodele O Majekodunmi
- Emergency Centre for Transboundary Diseases (ECTAD), Food and Agriculture Organisation of the United Nations, Rome, Italy
| | - Lenaig Halos
- Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Frans Jongejan
- United Nations Food and Agriculture Organisation, Rome, Italy
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10
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Dzemo WD, Vudriko P, Ramatla T, Thekisoe O. Acaricide Resistance Development in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) Populations against Amitraz and Deltamethrin on Communal Farms of the King Sabata Dalindyebo Municipality, South Africa. Pathogens 2023; 12:875. [PMID: 37513722 PMCID: PMC10383965 DOI: 10.3390/pathogens12070875] [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: 05/19/2023] [Revised: 06/08/2023] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
Chemical acaricides are widely used to control ticks and tick-borne pathogens in cattle. However, prolonged and indiscriminate use of these chemicals inevitably leads to the selection of resistant ticks. In-vitro bioassays (adult and larval immersion tests) were conducted to assess amitraz and deltamethrin resistance in Rhipicephalus (Boophilus) microplus populations from communal farms of the King Sabata Dalindyebo municipality of South Africa. Data generated on percentage inhibition of oviposition (%IO) revealed that all the tick populations assessed showed resistance (%IO ≤ 95%) to at least one of the acaricides. All six tick populations assessed for efficacy (%IO ≥ 95%) at the DD) with deltamethrin were resistant (%IO ≤ 95%) and only one of the six tick populations assessed for efficacy with amitraz was susceptible. Based on the resistance ratios (RR), the adult immersion test detected amitraz and deltamethrin resistance in three (RR ranging from 2.30 to 3.21) and five (RR ranging from 4.10 to 14.59) of the six tick populations, respectively. With the larval immersion test, deltamethrin and amitraz resistance (larval mortality < 90% at the DD) was detected in all four and three of four R. (B.) microplus populations assessed, respectively. These data are critical for the design of an effective and sustainable tick control strategy on the communal farms.
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Affiliation(s)
- William Diymba Dzemo
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University, Mthatha 5117, South Africa
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Patrick Vudriko
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala P.O. Box 7062, Uganda
| | - Tsepo Ramatla
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
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11
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Parizi LF, Githaka NW, Logullo C, Zhou J, Onuma M, Termignoni C, da Silva Vaz I. Universal Tick Vaccines: Candidates and Remaining Challenges. Animals (Basel) 2023; 13:2031. [PMID: 37370541 DOI: 10.3390/ani13122031] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 05/29/2023] [Accepted: 06/17/2023] [Indexed: 06/29/2023] Open
Abstract
Recent advancements in molecular biology, particularly regarding massively parallel sequencing technologies, have enabled scientists to gain more insight into the physiology of ticks. While there has been progress in identifying tick proteins and the pathways they are involved in, the specificities of tick-host interaction at the molecular level are not yet fully understood. Indeed, the development of effective commercial tick vaccines has been slower than expected. While omics studies have pointed to some potential vaccine immunogens, selecting suitable antigens for a multi-antigenic vaccine is very complex due to the participation of redundant molecules in biological pathways. The expansion of ticks and their pathogens into new territories and exposure to new hosts makes it necessary to evaluate vaccine efficacy in unusual and non-domestic host species. This situation makes ticks and tick-borne diseases an increasing threat to animal and human health globally, demanding an urgent availability of vaccines against multiple tick species and their pathogens. This review discusses the challenges and advancements in the search for universal tick vaccines, including promising new antigen candidates, and indicates future directions in this crucial research field.
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Affiliation(s)
- Luís Fernando Parizi
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 91501-970, Brazil
| | | | - Carlos Logullo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
| | - Jinlin Zhou
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Misao Onuma
- Department of Infectious Diseases, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Carlos Termignoni
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 91501-970, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
- Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 91501-970, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
- Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre 91540-000, Brazil
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12
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Tesfaye T, Abate A. Knowledge, attitude and practices study of acaricide usage and tick control in South Omo Zone pastoral areas, South-Western Ethiopia. Heliyon 2023; 9:e17212. [PMID: 37342571 PMCID: PMC10277579 DOI: 10.1016/j.heliyon.2023.e17212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 06/06/2023] [Accepted: 06/09/2023] [Indexed: 06/23/2023] Open
Abstract
Although acaricide chemotherapy is widely used to control tick infestation in Ethiopia, its effectiveness is uncertain due to misusage by herdsmen. Currently, there is no study being conducted in the South Omo Zone of Ethiopia which shows the knowledge, attitude, and practice (KAP) and associated factors of acaricide usage by herdsmen. Therefore, this study was conducted to assess KAP of 120 (83 male and 37 female) pastoralist and agro-pastoralist of Bena-Tsemay district through structured questionnaire survey. Accordingly, Ivermectin was the most preferred acaricide by majority (62.5%) of the herdsmen. Half (50%) of the herdsmen confessed that price of acaricide is the defining variable for acaricide preference in their location where 60.83% of them obtain acaricides from private drug shops. Majority (60%) of the respondents said that they obtain information about acaricide usage from drug sellers in the vet drug shops. According to 72.50% of the respondents, acaricide application/injection on the infested herd was conducted by the herdsmen. A 95.83% of our interviewee revealed that there was no training or awareness creation being given on how to inject or apply acaricide on tick infested animals. Moreover, all responders (100%) confessed that they didn't have a practice of weighing animals and measuring acaricide dosage prior to injection/application. The incidence of acaricide poisoning on animal and personnel was reported by 19.17% and 22.5% of respondents, respectively. Simple logistic regression analysis revealed that gender (OR = 5.09, OR 95% CI = 2.30-11.72), practice of acaricide rotation (OR = 3.22, OR 95% CI = 1.41-7.64) and personnel preference for acaricide application (OR = 2.66, OR 95% CI = 1.18-6.15) were significantly (P < 0.05) associated with the knowledge score of the respondents. On the other hand, respondent's attitude score was significantly (P < 0.05) associated with their acaricide rotation practice (OR = 3.20, OR 95% CI = 1.39-7.53) and personnel preference for acaricide application (OR = 6.61, OR 95% CI = 2.78-16.93). Similarly, practice of acaricide rotation (OR = 5.31, OR 95% CI = 2.26-12.96) and personnel preference for acaricide application (OR = 7.21, OR 95% CI = 3.03-17.99) were significantly linked with the practice score of the respondents towards acaricide usage. In conclusion, ticks are the major challenge in the study area despite widespread usage of acaricides. Because of extensive misusage of available acaricides, awareness creation should be applied to narrow KAP gaps and to conserve the efficacy of these chemicals. Furthermore, acaricide efficacy investigation (in vitro and in vivo) should be conducted to know the status of commonly used acaricides in the area.
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13
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Strydom T, Lavan RP, Torres S, Heaney K. The Economic Impact of Parasitism from Nematodes, Trematodes and Ticks on Beef Cattle Production. Animals (Basel) 2023; 13:1599. [PMID: 37238028 PMCID: PMC10215612 DOI: 10.3390/ani13101599] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/01/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
Global human population growth requires the consumption of more meat such as beef to meet human needs for protein intake. Cattle parasites are a constant and serious threat to the development of the beef cattle industry. Studies have shown that parasites not only reduce the performance of beef cattle, but also negatively affect the profitability of beef agriculture and have many other impacts, including contributing to the production of greenhouse gases. In addition, some zoonotic parasitic diseases may also threaten human health. Therefore, ongoing cattle parasite research is crucial for continual parasite control and the development of the beef cattle industry. Parasitism challenges profitable beef production by reducing feed efficiency, immune function, reproductive efficiency, liveweight, milk yield, calf yield and carcass weight, and leads to liver condemnations and disease transmission. Globally, beef cattle producers incur billions (US$) in losses due to parasitism annually, with gastrointestinal nematodes (GIN) and cattle ticks causing the greatest economic impact. The enormity of losses justifies parasitic control measures to protect profits and improve animal welfare. Geographical differences in production environment, management practices, climate, cattle age and genotype, parasite epidemiology and susceptibility to chemotherapies necessitate control methods customized for each farm. Appropriate use of anthelmintics, endectocides and acaricides have widely been shown to result in net positive return on investment. Implementing strategic parasite control measures, with thorough knowledge of parasite risk, prevalence, parasiticide resistance profiles and prices can result in positive economic returns for beef cattle farmers in all sectors.
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Affiliation(s)
- Tom Strydom
- MSD Animal Health, 20 Spartan Road, Isando, Kempton Park 1619, South Africa;
| | - Robert P. Lavan
- Merck & Co., Inc., 126 E. Lincoln Avenue, Rahway, NJ 07065, USA
| | - Siddhartha Torres
- Merck Animal Health, 2 Giralda Farms, Madison, NJ 07940, USA; (S.T.); (K.H.)
| | - Kathleen Heaney
- Merck Animal Health, 2 Giralda Farms, Madison, NJ 07940, USA; (S.T.); (K.H.)
- Heaney Veterinary Consulting, 303 Fletcher Lake Avenue, Bradley Beach, NJ 07720, USA
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14
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Some MV, Biguezoton AS, Githaka N, Adakal H, Dayo GK, Belem A, Zoungrana S, Stachurski F, Chevillon C. The potential of Rhipicephalus microplus as a vector of Ehrlichia ruminantium in West Africa. Ticks Tick Borne Dis 2023; 14:102117. [PMID: 36603230 DOI: 10.1016/j.ttbdis.2022.102117] [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: 02/03/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 01/01/2023]
Abstract
Heartwater, or cowdriosis, is a virulent tick-borne rickettsial disease of ruminants caused by Ehrlichia ruminantium, biologically transmitted by Amblyomma species (A. variegatum in West Africa). In West Africa, this bacterium was recently reported to naturally infect the invasive cattle tick, Rhipicephalus microplus (Rm) through trans-ovarian transmission from replete adult females to offspring. A 'sheep-tick-sheep' cycle was set up to determine whether feeding the progeny of these ticks on naïve sheep could lead to infection, and to compare clinical outcomes resulting from this transmission with those observed following infection by the natural A. variegatum (Av) vector. Using local strains of ticks (KIMINI-Rm and KIMINI-Av) and of E. ruminantium (BK242), we recorded, using the PCR technique, the presence of bacterial DNA in ticks (larvae for Av and females for Rm) engorged on sheep inoculated by BK242-infected blood. The bacterial DNA was also detected in the next stages of the lifecycle of R. microplus (eggs and larvae), and in sheep infested either by those R. microplus larvae or by A. variegatum nymphs moulted from larvae engorged on blood-inoculated sheep. Bacterial infection in these sheep was demonstrated by detecting antibodies to E. ruminantium using the MAP1-B ELISA and by isolation of the bacterium on cell culture from blood. The sequences of PCS20 gene detected in ticks and sheep were identical to that of the BK242 strain. Our results confirm that R. microplus can acquire and transmit E. ruminantium to the next stage. However, this transmission resulted in a mild subclinical disease whereas severe clinical disease was observed in sheep infested by A. variegatum infected nymphs, suggesting differences in the tick/bacteria relationship. Future studies will focus on replicating these findings with ticks of different isolates and life stages to determine if R. microplus is playing a role in the epidemiology of heartwater in West Africa. Additionally, studies will investigate whether sheep that are seropositive due to infestation by E. ruminantium-infected R. microplus are subsequently protected against heartwater. Such data will add to our understanding of the possible impact of R. microplus in areas where it has become recently established.
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Affiliation(s)
- Mireille V Some
- Unité de recherche Maladies à Vecteurs et Biodiversité (UMaVeB), Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 454 Bobo-Dioulasso 01, Burkina Faso; Institut du Développement Rural (IDR), Université Nazi BONI, 01 BP 1091, Bobo-Dioulasso 01, Burkina Faso
| | - Abel S Biguezoton
- Unité de recherche Maladies à Vecteurs et Biodiversité (UMaVeB), Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 454 Bobo-Dioulasso 01, Burkina Faso.
| | - Naftaly Githaka
- Animal and Human Health Program, International Livestock Research Institute (ILRI), Nairobi, Kenya, P.O. Box 30709-00100, Nairobi, Kenya
| | - Hassane Adakal
- Département des Sciences et Techniques de l'Elevage (DSTE/FASE), Université Dan Dicko Dan Koulodo, Maradi BP 465, Niger
| | - Guiguigbaza-Kossigan Dayo
- Unité de recherche Maladies à Vecteurs et Biodiversité (UMaVeB), Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 454 Bobo-Dioulasso 01, Burkina Faso
| | - Adrien Belem
- Institut du Développement Rural (IDR), Université Nazi BONI, 01 BP 1091, Bobo-Dioulasso 01, Burkina Faso
| | - Sébastien Zoungrana
- Unité de recherche Maladies à Vecteurs et Biodiversité (UMaVeB), Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 454 Bobo-Dioulasso 01, Burkina Faso
| | - Frédéric Stachurski
- CIRAD, UMR ASTRE, Montpellier F-34398, France; ASTRE, Univ Montpellier, CIRAD, INRAE, Montpellier, France
| | - Christine Chevillon
- MIVEGEC (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle), Univ. Montpellier-CNRS-IRD, Montpellier, France
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15
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Inspiring Anti-Tick Vaccine Research, Development and Deployment in Tropical Africa for the Control of Cattle Ticks: Review and Insights. Vaccines (Basel) 2022; 11:vaccines11010099. [PMID: 36679944 PMCID: PMC9866923 DOI: 10.3390/vaccines11010099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/23/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
Ticks are worldwide ectoparasites to humans and animals, and are associated with numerous health and economic effects. Threatening over 80% of the global cattle population, tick and tick-borne diseases (TTBDs) particularly constrain livestock production in the East, Central and Southern Africa. This, therefore, makes their control critical to the sustainability of the animal industry in the region. Since ticks are developing resistance against acaricides, anti-tick vaccines (ATVs) have been proposed as an environmentally friendly control alternative. Whereas they have been used in Latin America and Australia to reduce tick populations, pathogenic infections and number of acaricide treatments, commercially registered ATVs have not been adopted in tropical Africa for tick control. This is majorly due to their limited protection against economically important tick species of Africa and lack of research. Recent advances in various omics technologies and reverse vaccinology have enabled the identification of many candidate anti-tick antigens (ATAs), and are likely to usher in the next generation of vaccines, for which Africa should prepare to embrace. Herein, we highlight some scientific principles and approaches that have been used to identify ATAs, outline characteristics of a desirable ATA for vaccine design and propose the need for African governments to investment in ATV research to develop vaccines relevant to local tick species (personalized vaccines). We have also discussed the prospect of incorporating anti-tick vaccines into the integrated TTBDs control strategies in the sub-Saharan Africa, citing the case of Uganda.
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