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Jongejan F, Berger L, Reck J, Ferreira PT, de Jesus MS, Scott FB, de Avelar BR, Guimarães BG, Correia TR, Muhanguzi D, Vudriko P, Byaruhanga J, Tumwebaze M, Nagagi Y, Temba V, Biguezoton AS, Farougou S, Adehan S, Jumba H, Homminga L, Hulsebos I, Petersen A, Klafke G. RaTexT®: a novel rapid tick exposure test for detecting acaricide resistance in Rhipicephalus microplus ticks in Brazil. Parasit Vectors 2024; 17:365. [PMID: 39198870 PMCID: PMC11360494 DOI: 10.1186/s13071-024-06448-6] [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: 06/09/2024] [Accepted: 08/13/2024] [Indexed: 09/01/2024] Open
Abstract
BACKGROUND Acaricide resistance in cattle ticks is a significant concern in (sub)tropical regions, particularly Brazil. The Larval Packet Test (LPT) is the standard laboratory bioassay for resistance diagnosis, which requires triplicates of seven acaricidal dilutions plus controls to cover larval mortalities ranging between 0 and 100%. The value of the LPT lies in providing resistance ratios based on the ratio between the LC50 calculated with potentially resistant and susceptible ticks. However, LC50 ratios are difficult to translate into practical advice for farmers. Moreover, LPT requires laboratory facilities to maintain susceptible tick colonies, and it takes 6 weeks to obtain the larvae to be tested by LPT derived from engorged female ticks collected from cattle in the field. Our novel approach was twofold: first, we upgraded the LPT to the Resistance Intensity Test (RIT) by adopting the latest WHO guidelines for resistance detection in mosquitoes, which combines a 1 × recommended dose with 5 × and 10 × concentrated doses to reveal low, moderate and high resistance intensity, respectively. This reduced the number of test papers and tick larvae and, more importantly, provided relevant information on the resistance level. Our second innovative step was to abolish testing larvae entirely and expose partly engorged adult ticks to the same acaricidal doses immediately after removing them from cattle in the field. This resulted in the Rapid Tick exposure Test (RaTexT®), wherein partly engorged adult ticks were exposed to an acaricide-impregnated, specially designed matrix providing test results within 24 h. This approach directly compared resistance detection in tick larvae in the RIT with resistance in adult ticks in RaTexT®. METHODS Laboratory validation was conducted in Brazil with resistant and susceptible colonies of Rhipicephalus microplus ticks. For field validation, adult R. microplus ticks collected from different cattle farms in Brazil were evaluated for resistance to RaTexT®, and the results regarding their larval progenies were compared with those for the RIT. Partly engorged adult ticks derived from cattle infested with laboratory and field strains of R. microplus were exposed to deltamethrin in RaTexT® containers, which contained six rows of four interconnected compartments, accommodating five to eight semi-engorged female ticks with a preferred size ranging between 5 and 8 mm. The corresponding larvae of each strain were exposed in the RIT to the same deltamethrin concentrations in filter papers. RESULTS In RaTexT®, mortality in adult ticks from a resistant strain of R. microplus from Seropédica in Brazil was 38.4%, 54.2% and 75.0% at the 1 ×, 5 × and 10 × doses of deltamethrin, respectively. In RIT, mortality of larvae from the same resistant strain was 2.0%, 4.9% and 19.5% at 1 ×, 5 × and 10 × doses, respectively. The results of RaTexT® and RIT agreed since both tests identified a high level of resistance based on a cut-off of 90% mortality. In RaTexT®, mortality of adult ticks from a susceptible strain originating from Porto Alegre was 73.8%, 92.9% and 97.6% at the 1 ×, 5 × and 10 × doses, respectively. In RIT, mortality of larvae from the susceptible strain was 95.2%, 95.2% and 96.8% at the 1 ×, 5 × and 10 × doses, respectively. Interestingly, both tests identified a low number of unexpected resistant individuals in the susceptible strain since the mortality of neither larvae nor adults reached 100%. This effect remained unnoticed in the LPT, wherein a resistance ratio of 159.5 was found based on the LC50 of the resistant strain divided by the LC50 of the susceptible strain. Next, RaTexT® was compared with RIT using adult and larval ticks derived from three field strains of R. microplus in Brazil. RaTexT® detected high levels of resistance to deltamethrin in adult ticks in all strains, which was confirmed in larvae tested by the RIT. Both tests agreed on the same resistance level with significantly lower mortality rates in larvae than in adult ticks. CONCLUSIONS RaTexT® is a novel rapid pen-site test for detecting acaricide resistance in adult livestock ticks. It potentially replaces laborious tests using larval ticks and provides results within 24 h relevant to acaricide resistance management of livestock ticks.
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Affiliation(s)
- Frans Jongejan
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, Republic of South Africa.
- TBD International BV, BioScience Center, Wageningen University & Research, Runderweg 6, 8219 PK, Lelystad, The Netherlands.
| | - Laura Berger
- TBD International BV, BioScience Center, Wageningen University & Research, Runderweg 6, 8219 PK, Lelystad, The Netherlands
| | - José Reck
- Instituto de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde, 6000, Eldorado do Sul, RS, 92990-000, Brazil
| | - Priscila Teixeira Ferreira
- Instituto de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde, 6000, Eldorado do Sul, RS, 92990-000, Brazil
| | - Mariana Silveira de Jesus
- Instituto de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde, 6000, Eldorado do Sul, RS, 92990-000, Brazil
| | - Fabio Barbour Scott
- Instituto de Veterinária da Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, BR-465, Brazil
| | - Barbara Rauta de Avelar
- Instituto de Veterinária da Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, BR-465, Brazil
| | - Brena Gava Guimarães
- Instituto de Veterinária da Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, BR-465, Brazil
| | - Thais Ribeiro Correia
- Instituto de Veterinária da Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, BR-465, Brazil
| | - Dennis Muhanguzi
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Patrick Vudriko
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Joseph Byaruhanga
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Maria Tumwebaze
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Yakob Nagagi
- Tanzania Plant Health and Pesticides Authority (TPHPA), P.O. Box 3024, Arusha, Tanzania
| | - Violet Temba
- Tanzania Plant Health and Pesticides Authority (TPHPA), P.O. Box 3024, Arusha, Tanzania
| | - Abel S Biguezoton
- Centre International de Recherche-Développement sur l'élevage en zone Subhumide (CIRDES) Bobo-Dioulasso, Bobo-Dioulasso, Burkina Faso
| | - Souaïbou Farougou
- Ecole Polytechnique d'Abomey-Calavi, Université Abomey-Calavi, Cotonou, Republic of Benin
| | - Safiou Adehan
- Ecole Polytechnique d'Abomey-Calavi, Université Abomey-Calavi, Cotonou, Republic of Benin
| | - Humphrey Jumba
- International Livestock Research Institute, P.O.Box 30709, Nairobi, 00100, Kenya
| | - Laura Homminga
- TBD International BV, BioScience Center, Wageningen University & Research, Runderweg 6, 8219 PK, Lelystad, The Netherlands
| | - Iris Hulsebos
- TBD International BV, BioScience Center, Wageningen University & Research, Runderweg 6, 8219 PK, Lelystad, The Netherlands
| | - Alita Petersen
- TBD International BV, BioScience Center, Wageningen University & Research, Runderweg 6, 8219 PK, Lelystad, The Netherlands
| | - Guilherme Klafke
- Instituto de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde, 6000, Eldorado do Sul, RS, 92990-000, Brazil.
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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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Etiang P, Atim SA, Nkamwesiga J, Nalumenya D, Byaruhanga C, Odongo S, Vudriko P, Ademun AR, Biryomumaisho S, Erume J, Masembe C, Thomson EC, Muhanguzi D, Tweyongyere R. Identification and distribution of Rhipicephalus microplus in selected high-cattle density districts in Uganda: signaling future demand for novel tick control approaches. BMC Vet Res 2024; 20:119. [PMID: 38528496 DOI: 10.1186/s12917-024-03979-z] [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: 12/15/2023] [Accepted: 03/15/2024] [Indexed: 03/27/2024] Open
Abstract
BACKGROUND Rhipicephalus (Boophilus) microplus (Canestrini, 1888), the Asian blue tick, is a highly invasive and adaptable ectoparasite. This tick species has successfully established itself in most regions of the world, with movement of cattle being a major driver for its spread. In the recent past, R. microplus ticks have been reported in three districts of Uganda. Information on its spread and distribution are vital in deepening our understanding of the ecological scenarios that lead to tick persistence and in the formulation of control strategies. This is especially important in the cattle-dense districts. METHODS We randomly collected tick specimens from 1,461cattle spread across seven cattle dense districts located in the Central, Karamoja and West Nile regions of Uganda from January to September 2020. The ticks were identified using standard morpho-taxonomic keys and the R. microplus tick species identities were confirmed by sequencing of the ITS2 region, 12S rRNA and 16S rRNA genes and phylogenetic analyses. RESULTS Adult ticks (n = 13,019) were collected from 1,461 cattle. Seventeen tick species were identified based on morpho-taxonomic keys and the majority (47.4%; n=6184) of these were R. appendiculatus. In total, 257 R. microplus ticks were found infesting cattle in 18 study sites in the districts of Amudat, Kaabong, Napak (Karamoja region) and Arua (West Nile region). The identity of R. microplus was confirmed using molecular technics. No R. microplus tick was recorded in the districts of Lyantonde and Nakaseke (Central region). Arua district accounted for 82.1% (n=211) of the R. microplus ticks recorded followed by Napak district at 16.3% (n=42), while Amudat and Kaabong districts accounted for 1.5% (n=4). Rhipicephalus microplus and R. decoloratus co-existed in 6 of the 13 study sites in Arua district, while in another 6 study sites, no R. decoloratus was recorded. In the Karamoja region districts R. decoloratus co-existed with R.microplus. Of the total 618 ticks belonging to four species of the subgenus Boophilus recorded in this study, R. decoloratus accounted for 50.04% (n=334), followed by R. microplus at 41.58% (n=257), R. geigyi at 2.75% (n=17) and R. annulatus at 1.61% (n=10). In the districts of Amudat, Kaabong and Napak, R. decoloratus was more dominant (76.1%; n=179) of the three Rhipicephalus (Boophilus) tick species recorded, followed by R. microplus (19.5%; n=46) and R. geigyi (4.2%; n=10). Contrariwise, R. microplus was more dominant (84%; n=211) in Arua district followed by R. decoloratus (10.7%; n=27), R. annulatus (3.9%; n=10) and R. geigyi (1.1%; n=3). Phylogenetic analyses of the ITS2 region, 12S rRNA and 16S rRNA genes revealed subgrouping of the obtained sequences with the previously published R. microplus sequences from other parts of the world. CONCLUSION Rhipicephalus microplus ticks were found infesting cattle in four districts of Uganda. The inability to find R. decoloratus, an indigenous tick, from six sites in the district of Arua is suggestive of its replacement by R. microplus. Rhipicephalus microplus negatively affects livestock production, and therefore, there is a need to determine its distribution and to deepen the understanding of the ecological factors that lead to its spread and persistence in an area.
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Affiliation(s)
- Patrick Etiang
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
- Faculty of Agriculture and Animal Sciences, Busitema University, P.O. Box 236, Tororo, Uganda
| | - Stella A Atim
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
- Ministry of Agriculture, Animal Industry and Fisheries, P.O. Box 102, Entebbe, Uganda
| | - Joseph Nkamwesiga
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - David Nalumenya
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Charles Byaruhanga
- National Agricultural Research Organization, P.O. Box 259, Entebbe, Uganda
- Vectors and Vector-Borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa
| | - Steven Odongo
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Patrick Vudriko
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Anna Rose Ademun
- Ministry of Agriculture, Animal Industry and Fisheries, P.O. Box 102, Entebbe, Uganda
| | - Savino Biryomumaisho
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Joseph Erume
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Charles Masembe
- College of Natural Sciences (CONAS), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Emma C Thomson
- MRC-University of Glasgow Centre for Virus Research (CVR), Glasgow, United Kingdom
| | - Dennis Muhanguzi
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Robert Tweyongyere
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, P.O. Box 7062, Kampala, Uganda.
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Elati K, Daly N, Dhibi M, Laaribi H, Rekik M, Gharbi M. Repeated Cross-Sectional Survey of Ectoparasites in Sheep from Central Tunisia: Does Low Prevalence Indicate Good Hygiene or Resistance to Ectoparasites? Animals (Basel) 2024; 14:801. [PMID: 38473186 DOI: 10.3390/ani14050801] [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: 01/17/2024] [Revised: 02/26/2024] [Accepted: 03/02/2024] [Indexed: 03/14/2024] Open
Abstract
Sheep ectoparasites such as chewing lice, fleas and ticks are serious constraints to sheep productivity and are the cause of skin lesions in animals that decrease their market value. This study aims at investigating the ectoparasite fauna infesting small ruminants in the district of Sidi Bouzid (central Tunisia). A total of 1243 Barbarine and Queue Fine de l'Ouest (QFO) sheep were examined every two months for one year. Of the total animals examined, 74 were infested by at least 1 parasite group (5.95%). Three ectoparasite groups were identified as Psoroptes ovis (0.48%; 6/1243), ticks (5.3%; n = 66/1243) and one specimen of Ctenocephalides canis (0.08%; n = 1/1243). The most abundant tick among the 358 specimens was Rhipicephalus sanguineus sensu lato (n = 337; 94.1%), followed by Hyalomma impeltatum (n = 7/358; 1.9%), H. dromedarii (n = 7/358; 1.9%), H. excavatum (n = 5/358; 1.4%) and only two specimens of H. scupense (n = 2/358; 0.55%). The sheep herds showed low infestation prevalence by ectoparasite over the year, with a significant difference according to the seasons (p < 0.05). A higher infestation prevalence was recorded in March (14.36%). Barbarine sheep breed showed significantly higher infestation prevalence (16.8%) compared to QFO (0.8%) (p < 0.01). There were no differences in infestation prevalence according to sex of the animal or age groups. Knowledge of the ectoparasite population harboured by sheep, its activity dynamics and risk factors is required to develop effective ectoparasite control options. The low prevalence of ectoparasite infestation in sheep reported here may be due to possible genetic resistance or simply to successful hygiene measures implemented by farmers.
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Affiliation(s)
- Khawla Elati
- Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7, 14163 Berlin, Germany
- Veterinary Centre for Resistance Research, Freie Universität Berlin, Robert-Von-Ostertag-Str. 8, 14163 Berlin, Germany
| | - Nesrine Daly
- Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
| | - Mokhtar Dhibi
- Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
| | - Hela Laaribi
- Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
| | - Mourad Rekik
- International Center for Agricultural Research in the Dry Areas (ICARDA), P.O. Box 950764, Amman 11195, Jordan
| | - Mohamed Gharbi
- Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
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Lilak AA, Pecor DB, Matulis G, Potter AM, Wofford RN, Kearney MF, Mitchell S, Jaradat F, Kano A, Zimmerman DM, Hassell JM, Kumsa B, Kamau M, Linton YM, von Fricken ME. Data release: targeted systematic literature search for tick and tick-borne pathogen distributions in six countries in sub-Saharan Africa from 1901 to 2020. Parasit Vectors 2024; 17:84. [PMID: 38389097 PMCID: PMC10885379 DOI: 10.1186/s13071-023-06086-4] [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: 09/11/2023] [Accepted: 12/07/2023] [Indexed: 02/24/2024] Open
Abstract
BACKGROUND Surveillance data documenting tick and tick-borne disease (TBD) prevalence is needed to develop risk assessments and implement control strategies. Despite extensive research in Africa, there is no standardized, comprehensive review. METHODS Here we tackle this knowledge gap, by producing a comprehensive review of research articles on ticks and TBD between 1901 and 2020 in Chad, Djibouti, Ethiopia, Kenya, Tanzania, and Uganda. Over 8356 English language articles were recovered. Our search strategy included 19 related MeSH terms. Articles were reviewed, and 331 met inclusion criteria. Articles containing mappable data were compiled into a standardized data schema, georeferenced, and uploaded to VectorMap. RESULTS Tick and pathogen matrixes were created, providing information on vector distributions and tick-pathogen associations within the six selected African countries. CONCLUSIONS These results provide a digital, mappable database of current and historical tick and TBD distributions across six countries in Africa, which can inform specific risk modeling, determine surveillance gaps, and guide future surveillance priorities.
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Affiliation(s)
- Abigail A Lilak
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA
| | - David B Pecor
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | - Graham Matulis
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA
| | - Alexander M Potter
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | | | | | - Stephanie Mitchell
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
| | | | - Arisa Kano
- George Mason University, Fairfax, VA, USA
| | - Dawn M Zimmerman
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- Yale University, New Haven, CT, USA
| | - James M Hassell
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- Yale University, New Haven, CT, USA
| | - Bersissa Kumsa
- Department of Pathology & Parasitology, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Ethiopia
| | - Maureen Kamau
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Mpala Research Center, Nanyuki, Kenya
| | - Yvonne-Marie Linton
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | - Michael E von Fricken
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA.
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA.
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Chaka B, Osano AM, Wesley ON, Forbes PBC. Seasonal variation in pesticide residue occurrences in surface waters found in Narok and Bomet Counties, Kenya. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:1050. [PMID: 37589911 DOI: 10.1007/s10661-023-11629-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/22/2023] [Indexed: 08/18/2023]
Abstract
Narok and Bomet are agricultural counties in Kenya which depend on flowing surface waters for farming activities. Agrochemicals have frequently been used to increase agricultural produce in this region. Occasionally, appropriate pesticide utilization measures are not followed. These surface waters are also consumed domestically by humans, livestock, and wild animals thus posing safety concerns to them. The current study sought to evaluate the levels and nature of pesticide residues found in surface waters in the dry and wet seasons of these counties. Eight water samples were collected in July (dry season) and October (wet season) at four different river sites in each of the two counties predetermined by the agricultural activity of its proximate environs. Pesticides extracted by solid phase extraction were analyzed by gas chromatography-mass spectrometry. At least 38 different pesticides were detected in the two counties with the highest concentration being recorded for chlorpyrifos and piperidine in Narok and Bomet counties, respectively. The pesticides chlorpyrifos, cypermethrin, cyfluthrin, and cyhalothrin were more prevalent in Narok County while triazine, semicarbazone, and epinephrine were more prevalent in Bomet County. There were significantly more pesticides detected during the wet season (P ≤ 0.05). Out of the nine prevalent pesticides detected, four of them posed serious ecotoxicology concerns with risk quotients above 1.0 (high risk); thus, there is a need for more government policy interventions in deterring farming near riparian lands and in training of famers regarding best practice for pesticide applications.
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Affiliation(s)
- Bakari Chaka
- Department of Mathematics and Physical Sciences, Maasai Mara University, P.O. Box 861-20500, Narok, Kenya
| | - Aloys M Osano
- Department of Mathematics and Physical Sciences, Maasai Mara University, P.O. Box 861-20500, Narok, Kenya.
| | - Omwoyo N Wesley
- Department of Mathematics and Physical Sciences, Maasai Mara University, P.O. Box 861-20500, Narok, Kenya
| | - Patricia B C Forbes
- Department of Chemistry, Faculty of Agriculture and Natural Sciences, University of Pretoria, Pretoria, 0002, South Africa
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Santos JHM, Siddle HV, Raza A, Stanisic DI, Good MF, Tabor AE. Exploring the landscape of Babesia bovis vaccines: progress, challenges, and opportunities. Parasit Vectors 2023; 16:274. [PMID: 37563668 PMCID: PMC10413621 DOI: 10.1186/s13071-023-05885-z] [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: 05/24/2023] [Accepted: 07/17/2023] [Indexed: 08/12/2023] Open
Abstract
Bovine babesiosis, caused by different Babesia spp. such as B. bovis, B. bigemina, B. divergens, and B. major, is a global disease that poses a serious threat to livestock production. Babesia bovis infections are associated with severe disease and increased mortality in adult cattle, making it the most virulent agent of bovine babesiosis. Babesia bovis parasites undergo asexual reproduction within bovine red blood cells, followed by sexual reproduction within their tick vectors, which transmit the parasite transovarially. Current control methods, including therapeutic drugs (i.e., imidocarb) have been found to lead to drug resistance. Moreover, changing environmental factors add complexity to efficient parasite control. Understanding the fundamental biology, host immune responses, and host-parasite interactions of Babesia parasites is critical for developing next-generation vaccines to control acute disease and parasite transmission. This systematic review analyzed available research papers on vaccine development and the associated immune responses to B. bovis. We compiled and consolidated the reported vaccine strategies, considering the study design and rationale of each study, to provide a systematic review of knowledge and insights for further research. Thirteen studies published since 2014 (inclusive) represented various vaccine strategies developed against B. bovis such as subunit, live attenuated, and viral vector vaccines. Such strategies incorporated B. bovis proteins or whole live parasites with the latter providing the most effective prophylaxis against bovine babesiosis. Incorporating novel research approaches, such as "omics" will enhance our understanding of parasite vulnerabilities.
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Affiliation(s)
- John Harvey M Santos
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Hannah V Siddle
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Ali Raza
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Danielle I Stanisic
- Griffith University, Institute for Glycomics, Southport, Qld, 4215, Australia
| | - Michael F Good
- Griffith University, Institute for Glycomics, Southport, Qld, 4215, Australia
| | - Ala E Tabor
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia.
- The University of Queensland, School of Chemistry & Molecular Biosciences, St Lucia, Qld, 4072, Australia.
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Eneku W, Erima B, Byaruhanga AM, Atim G, Tugume T, Ukuli QA, Kibuuka H, Mworozi E, Douglas C, Koehler JW, Cleary NG, von Fricken ME, Tweyongyere R, Wabwire-Mangen F, Byarugaba DK. Wide distribution of Mediterranean and African spotted fever agents and the first identification of Israeli spotted fever agent in ticks in Uganda. PLoS Negl Trop Dis 2023; 17:e0011273. [PMID: 37498943 PMCID: PMC10409254 DOI: 10.1371/journal.pntd.0011273] [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: 04/04/2023] [Revised: 08/08/2023] [Accepted: 07/12/2023] [Indexed: 07/29/2023] Open
Abstract
Rickettsia microorganisms are causative agents of several neglected emerging infectious diseases in humans transmitted by arthropods including ticks. In this study, ticks were collected from four geographical regions of Uganda and pooled in sizes of 1-179 ticks based on location, tick species, life stage, host, and time of collection. Then, they were tested by real-time PCR for Rickettsia species with primers targeting gltA, 17kDa and ompA genes, followed by Sanger sequencing of the 17kDa and ompA genes. Of the 471 tick pools tested, 116 (24.6%) were positive for Rickettsia spp. by the gltA primers. The prevalence of Rickettsia varied by district with Gulu recording the highest (30.1%) followed by Luwero (28.1%) and Kasese had the lowest (14%). Tick pools from livestock (cattle, goats, sheep, and pigs) had the highest positivity rate, 26.9%, followed by vegetation, 23.1%, and pets (dogs and cats), 19.7%. Of 116 gltA-positive tick pools, 86 pools were positive using 17kDa primers of which 48 purified PCR products were successfully sequenced. The predominant Rickettsia spp. identified was R. africae (n = 15) in four tick species, followed by R. conorii (n = 5) in three tick species (Haemaphysalis elliptica, Rhipicephalus appendiculatus, and Rh. decoloratus). Rickettsia conorii subsp. israelensis was detected in one tick pool. These findings indicate that multiple Rickettsia spp. capable of causing human illness are circulating in the four diverse geographical regions of Uganda including new strains previously known to occur in the Mediterranean region. Physicians should be informed about Rickettsia spp. as potential causes of acute febrile illnesses in these regions. Continued and expanded surveillance is essential to further identify and locate potential hotspots with Rickettsia spp. of concern.
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Affiliation(s)
- Wilfred Eneku
- Makerere University, College of Veterinary Medicine, Kampala, Uganda
- Makerere University Walter Reed Project, Kampala, Uganda
| | - Bernard Erima
- Makerere University Walter Reed Project, Kampala, Uganda
| | | | - Gladys Atim
- Makerere University Walter Reed Project, Kampala, Uganda
| | - Titus Tugume
- Makerere University Walter Reed Project, Kampala, Uganda
| | | | - Hannah Kibuuka
- Makerere University Walter Reed Project, Kampala, Uganda
| | - Edison Mworozi
- Makerere University, College of Health Sciences, Kampala, Uganda
| | - Christina Douglas
- Diagnostic Systems Division, USAMRIID, Fort Detrick, Maryland, United States of America
| | - Jeffrey W. Koehler
- Diagnostic Systems Division, USAMRIID, Fort Detrick, Maryland, United States of America
| | - Nora G. Cleary
- Global and Community Health, George Mason University, Fairfax, Virginia, United States of America
| | - Michael E. von Fricken
- Global and Community Health, George Mason University, Fairfax, Virginia, United States of America
| | | | - Fred Wabwire-Mangen
- Makerere University Walter Reed Project, Kampala, Uganda
- Makerere University, School of Public Health, Kampala, Uganda
| | - Denis Karuhize Byarugaba
- Makerere University, College of Veterinary Medicine, Kampala, Uganda
- Makerere University Walter Reed Project, Kampala, Uganda
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Nemaungwe TM, van Dalen EMSP, Waniwa EO, Makaya PV, Chikowore G, Chidawanyika F. Biogeography of the theileriosis vector, Rhipicephalus appendiculatus under current and future climate scenarios of Zimbabwe. EXPERIMENTAL & APPLIED ACAROLOGY 2023:10.1007/s10493-023-00796-1. [PMID: 37171505 PMCID: PMC10293362 DOI: 10.1007/s10493-023-00796-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 04/25/2023] [Indexed: 05/13/2023]
Abstract
Climate directly influences the epidemiology of vector-borne diseases at various spatial and temporal scales. Following the recent increased incidences of theileriosis in Zimbabwe, a disease mainly transmitted by Rhipicephalus appendiculatus, we determined lethal temperatures for the species and current and possible future distribution using the machine learning algorithm 'Maxent'. Rhipicephalus appendiculatus larvae had an upper lethal temperature (ULT50) of about 44 ± 0.5 °C and this was marginally higher for nymphs and adults at 46 ± 0.5 °C. Environmental temperatures recorded in selected zonal tick microhabitats were below the determined lethal limits, indicating the ability of the tick to survive these regions. The resultant model under current climatic conditions showed areas with high suitability indices to the eastern, northeastern and southeastern parts of the country, mainly in Masvingo, Manicaland and Mashonaland Central provinces. Future predictions as determined by 2050 climatic conditions indicate a reduction in suitable habitats with the tick receding to presently cooler high elevation areas such as the eastern Highlands of Zimbabwe and a few isolated pockets in the interior of the country. Lowveld areas show low suitability under current climatic conditions and are expected to remain unsuitable in future. Overall, the study shows that R. appendiculatus distribution is constrained by climatic factors and helps identify areas of where occurrence of the species and the disease it transmits is highly likely. This will assist in optimizing disease surveillance and vector management strategies targeted at the species.
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Affiliation(s)
- Tinotenda M Nemaungwe
- Division of Veterinary Technical Services, Ministry of Lands, Fisheries, Water and Rural Development, Harare, Zimbabwe
- Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
| | - Ellie M S P van Dalen
- Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
| | - Emily O Waniwa
- Division of Veterinary Technical Services, Ministry of Lands, Fisheries, Water and Rural Development, Harare, Zimbabwe
| | - Pious V Makaya
- Division of Veterinary Technical Services, Ministry of Lands, Fisheries, Water and Rural Development, Harare, Zimbabwe
| | - Gerald Chikowore
- Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa
- Centre for Biological Control, Department of Zoology and Entomology, Rhodes University, Grahamstown, 6140, South Africa
| | - Frank Chidawanyika
- Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa.
- International Centre of Insect Physiology and Ecology (icipe), PO Box 30772-00100, Nairobi, Kenya.
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Achuthkumar A, Uchamballi S, Arvind K, Vasu DA, Varghese S, Ravindran R, Grace T. Transcriptome Profiling of Rhipicephalus annulatus Reveals Differential Gene Expression of Metabolic Detoxifying Enzymes in Response to Acaricide Treatment. Biomedicines 2023; 11:biomedicines11051369. [PMID: 37239047 DOI: 10.3390/biomedicines11051369] [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: 01/05/2023] [Revised: 03/19/2023] [Accepted: 03/28/2023] [Indexed: 05/28/2023] Open
Abstract
Ticks are hematophagous ectoparasites of economic consequence by virtue of being carriers of infectious diseases that affect livestock and other sectors of the agricultural industry. A widely prevalent tick species, Rhipicephalus (Boophilus) annulatus, has been recognized as a prime vector of tick-borne diseases in South Indian regions. Over time, the use of chemical acaricides for tick control has promoted the evolution of resistance to these widely used compounds through metabolic detoxification. Identifying the genes related to this detoxification is extremely important, as it could help detect valid insecticide targets and develop novel strategies for effective insect control. We performed an RNA-sequencing analysis of acaricide-treated and untreated R. (B.) annulatus and mapped the detoxification genes expressed due to acaricide exposure. Our results provided high-quality RNA-sequenced data of untreated and amitraz-treated R. (B.) annulatus, and then the data were assembled into contigs and clustered into 50,591 and 71,711 uni-gene sequences, respectively. The expression levels of the detoxification genes across different developmental stages of R. (B.) annulatu identified 16,635 transcripts as upregulated and 15,539 transcripts as downregulated. The annotations of the differentially expressed genes (DEGs) revealed the significant expression of 70 detoxification genes in response to the amitraz treatment. The qRT-PCR revealed significant differences in the gene expression levels across different life stages of R. (B.) annulatus.
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Affiliation(s)
- Amritha Achuthkumar
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kasaragod 671320, Kerala, India
| | - Shamjana Uchamballi
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kasaragod 671320, Kerala, India
| | - Kumar Arvind
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kasaragod 671320, Kerala, India
| | - Deepa Azhchath Vasu
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kasaragod 671320, Kerala, India
| | - Sincy Varghese
- Department of Biochemistry, Pazhassiraja College, Pulpally 673579, Kerala, India
| | - Reghu Ravindran
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode 673576, Kerala, India
| | - Tony Grace
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Kasaragod 671320, Kerala, India
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Ogo NI, Weka R, Nnabuife HE, Uchendu C, Obeta S, Opara M. Knowledge, Attitudes, and Practices of Pastoralists Towards Tick Bites, and Tick Control in Plateau State, Nigeria. Acta Parasitol 2023:10.1007/s11686-023-00670-5. [PMID: 36976439 DOI: 10.1007/s11686-023-00670-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 03/07/2023] [Indexed: 03/29/2023]
Abstract
PURPOSE Pastoralists regularly come in contact with ticks as they herd their animals and are exposed to pathogens that cause zoonotic diseases. No study has been conducted in Nigeria to evaluate the knowledge, attitudes, and practices (KAP) of these Pastoralists towards ticks, tick bite, and tick control, and thus this research. METHODS A KAP survey of pastoralists (n = 119) was conducted in Plateau State, Nigeria. Data generated were analysed using Statistical Package for Social Sciences (SPSS). RESULTS The majority of the pastoralists (99.2%) had knowledge of ticks, with 79% of them being aware that ticks attach and bite humans, whereas only 30.3% believed that ticks transmit diseases to humans. Eighty-four per cent of the pastoralists do not wear protective clothing while herding their animals and 81.5% indicated to having been bitten by ticks, whereas hospital visit after tick bite was low (7.6%). Statistically significant variables were observed when knowledge of the respondents were compared in relation to the ability of ticks to cause diseases (Χ2 = 9.980, P = 0.007); hospital visit after a bite (Χ2 = 11.453, P = 0.003); and the use of protective clothing for herding (Χ2 = 22.596, P = 0). The main tick control measure was hand picking (58.8%). CONCLUSIONS The pastoralists were unaware of the ability of ticks to transmit zoonotic pathogens. Preventive practices were insufficient to reduce tick bites, and thus were constantly exposed to tick-borne diseases. This study hopes to provide important insights for the development of educational awareness programmes for the pastoralists and serve as a guide for the health workers in designing future preventive programmes against tick-borne zoonoses in Nigeria.
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Affiliation(s)
- Ndudim Isaac Ogo
- Parasitology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
| | - Rebecca Weka
- Parasitology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria
| | - Henry Ekene Nnabuife
- Parasitology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria
| | - Chidebere Uchendu
- Department of Physiology, Biochemistry and Pharmacology, Faculty of Veterinary Medicine, University of Jos, Jos, Plateau State, Nigeria
| | - Sylvester Obeta
- Department of Veterinary Parasitology and Entomology, University of Abuja, Abuja, Nigeria
| | - Maxwell Opara
- Department of Veterinary Parasitology and Entomology, University of Abuja, Abuja, Nigeria
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Showler AT, Harlien JL. Desiccant Dusts, With and Without Bioactive Botanicals, Lethal to Rhipicephalus (Boophilus) microplus Canestrini (Ixodida: Ixodidae) in the Laboratory and on Cattle. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:346-355. [PMID: 36734019 DOI: 10.1093/jme/tjad010] [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: 11/06/2022] [Indexed: 06/18/2023]
Abstract
The exotic southern cattle fever tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Ixodida: Ixodidae), since its eradication from the United States in 1943, made a strong incursion into Texas, beginning 2016. The pest is arguably the most economically detrimental ectoparasite of cattle, Bos taurus L., worldwide. Current R. (B.) microplus control mostly relies on conventional synthetic acaricides to which the ixodid has been developing resistance. Our study demonstrates that commercially available desiccant dust products, with and without bioactive botanical additives, are strongly lethal, when applied dry, against larval R. (B.) microplus in the laboratory, and after being released on dust-treated cattle. Deadzone (renamed Celite 610, a diatomaceous earth product), Drione (silica gel + pyrethrins + piperonyl butoxide synergist), and EcoVia (silica gel + thyme oil), each prophylactically prevented larval R. (B.) microplus from attaching to and feeding on stanchioned calves. Desiccant dust-based products are less likely than conventional synthetic acaricides to decline in terms of efficacy as a result of ixodid resistance, and other desiccant dust advantages, including extended residual, flexibility in terms of application methods, environmental, animal, and human safety, and possible compatibility with organic, or 'green', production systems, are discussed. We anticipate that the desiccant dusts we evaluated, and others not included in this study (e.g., kaolin, perlite, and silica gel) will be effective when used with other control tactics in integrated pest management approaches for controlling R. (B.) microplus (and other ixodid species).
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Affiliation(s)
- Allan T Showler
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX 78028, USA
| | - Jessica L Harlien
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX 78028, USA
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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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Oundo JW, Masiga D, ten Bosch Q, Villinger J, Koenraadt CJ, Kalayou S. Epidemiology of tick-borne pathogens of cattle and tick control practices in coastal Kenya. Prev Vet Med 2022; 209:105777. [DOI: 10.1016/j.prevetmed.2022.105777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/29/2022] [Accepted: 10/07/2022] [Indexed: 11/17/2022]
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Molecular Characterization of Octopamine/Tyramine Receptor Gene of Amitraz-Resistant Rhipicephalus ( Boophilus) decoloratus Ticks from Uganda. Microorganisms 2022; 10:microorganisms10122384. [PMID: 36557637 PMCID: PMC9788083 DOI: 10.3390/microorganisms10122384] [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: 10/17/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/04/2022] Open
Abstract
We previously reported the emergence of amitraz-resistant Rhipicephalus (Boophilus) decoloratus ticks in the western region of Uganda. This study characterized the octopamine/tyramine receptor gene (OCT/Tyr) of amitraz-resistant and -susceptible R. (B.) decoloratus ticks from four regions of Uganda. The OCT/Tyr gene was amplified from genomic DNA of 17 R. (B.) decoloratus larval populations of known susceptibility to amitraz. The amplicons were purified, cloned and sequenced to determine mutations in the partial coding region of the OCT/Tyr gene. The amplified R. (B.) decoloratus OCT/Tyr gene was 91-100% identical to the R. (B.) microplus OCT/Tyr gene. Up to 24 single nucleotide polymorphisms (SNPs) were found in the OCT/Tyr gene from ticks obtained from high acaricide pressure areas, compared to 8 from the low acaricide pressure areas. A total of eight amino acid mutations were recorded in the partial OCT/Tyr gene from ticks from the western region, and four of them were associated with amitraz-resistant tick populations. The amino acid mutations M1G, L16F, D41G and V72A were associated with phenotypic resistance to amitraz with no specific pattern. Phylogenetic analysis revealed that the OCT/Tyr gene sequence from this study clustered into two distinct groups that separated the genotype from high acaricide pressure areas from the susceptible populations. In conclusion, this study is the first to characterize the R. (B.) decoloratus OCT/Tyr receptor gene and reports four novel amino acid mutations associated with phenotypic amitraz resistance in Uganda. However, lack of mutations in the ORF of the OCT/Tyr gene fragment for some of the amitraz-resistant R. (B.) decoloratus ticks could suggest that other mechanisms of resistance may be responsible for amitraz resistance, hence the need for further investigation.
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Liu YK, Liu GH, Liu L, Wang AB, Cheng TY, Duan DY. Comparative analysis of the anticoagulant activities and immunogenicity of HSC70 and HSC70 TKD of Haemaphysalis flava. Parasit Vectors 2022; 15:411. [PMID: 36335395 PMCID: PMC9636643 DOI: 10.1186/s13071-022-05521-2] [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: 06/30/2022] [Accepted: 10/02/2022] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Haemaphysalis flava is a hematophagous ectoparasite that acquires the nutrition needed for development and reproduction by sucking blood and digesting the blood meal. During blood-sucking and blood-meal digestion, the prevention of blood coagulation is important for this tick. Previous studies have shown that heat shock cognate 70 (HSC70) protein has certain anticoagulant activities, but its immunogenicity remains unclear. Also, whether the mutation of individual bases of the TKD-like peptide of HSC70 through the overlap extension method can change its anticoagulant activities and immunogenicity remains to be investigated. METHODS The gene encoding the HSC70 protein was cloned from a complementary DNA library synthesized from H. flava. The coding gene of the TKD-like peptide of HSC70 was mutated into a TKD peptide coding gene (HSC70TKD) using the overlap extension method. Escherichia coli prokaryotic expression plasmids were constructed to obtain the recombinant proteins of HSC70 (rHSC70) and HSC70TKD (rHSC70TKD). The purified rHSC70 and rHSC70TKD were evaluated at different concentrations for anticoagulant activities using four in vitro clotting assays. Emulsifying recombinant proteins with complete and incomplete Freund's adjuvants were subcutaneously immunized in Sprague Dawley rats. The serum antibody titers and serum concentrations of interferon-gamma (IFN-γ) and interleukin-4 (IL-4) were detected using an indirect enzyme-linked immunosorbent assay to assess the immunogenicity of rHSC70 and rHSC70TKD. RESULTS The open reading frame of HSC70 was successfully amplified and found to have a length of 1958 bp. The gene encoding the TKD-like peptide of HSC70 was artificially mutated, with the 1373-position adenine (A) of the original sequence mutated into guanine (G), the 1385-position cytosine (C) mutated into G and the 1386-position G mutated into C. rHSC70 and rHSC70TKD that fused with His-tag were obtained using the expression plasmids pET-28a-HSC70 and pET-28a-HSC70TKD, respectively. rHSC70 and rHSC70TKD prolonged the thrombin time (TT) and reduced the fibrinogen (FIB) content in the plasma, but did not affect the prothrombin time (PT) or activated partial thromboplastin time (APTT) when compared to the negative control. Interestingly, the ability of rHSC70TKD to prolong the TT and reduce the FIB content in the plasma was better than that of rHSC70. The specific antibody titers of both rHSC70 and rHSC70TKD in rat serum reached 1:124,000 14 days after the third immunization. The serum concentration of IFN-γ in the rHSC70TKD group was higher than that in the rHSC70 group. The rHSC70 group has the highest serum concentration of IL-4, and the serum concentration of IL-4 in the rHSC70TKD group was higher than that in the negative group. CONCLUSIONS rHSC70 and rHSC70TKD exhibited anticoagulant activities by prolonging the TT and reducing the FIB content in vitro. rHSC70TKD had better anticoagulant activities than rHSC70. Both rHSC70 and rHSC70TKD had good immunogenicity and induced humoral and cellular immunity.
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Affiliation(s)
- Yu-Ke Liu
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
| | - Guo-Hua Liu
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
| | - Lei Liu
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
| | - Ai-Bing Wang
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
| | - Tian-Yin Cheng
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
| | - De-Yong Duan
- grid.257160.70000 0004 1761 0331Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128 Hunan Province China
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Singh K, Kumar S, Sharma AK, Jacob S, RamVerma M, Singh NK, Shakya M, Sankar M, Ghosh S. Economic impact of predominant ticks and tick-borne diseases on Indian dairy production systems. Exp Parasitol 2022; 243:108408. [DOI: 10.1016/j.exppara.2022.108408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/27/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022]
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Wulff JP, Temeyer KB, Tidwell JP, Schlechte KG, Lohmeyer KH, Pietrantonio PV. Periviscerokinin (Cap 2b; CAPA) receptor silencing in females of Rhipicephalus microplus reduces survival, weight and reproductive output. Parasit Vectors 2022; 15:359. [PMID: 36203198 PMCID: PMC9535995 DOI: 10.1186/s13071-022-05457-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/24/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The cattle fever tick, Rhipicephalus (Boophilus) microplus, is a vector of pathogens causative of babesiosis and anaplasmosis, both highly lethal bovine diseases that affect cattle worldwide. In Ecdysozoa, neuropeptides and their G-protein-coupled receptors play a critical integrative role in the regulation of all physiological processes. However, the physiological activity of many neuropeptides is still unknown in ticks. Periviscerokinins (CAP2b/PVKs) are neuropeptides associated with myotropic and diuretic activities in insects. These peptides have been identified only in a few tick species, such as Ixodes ricinus, Ixodes scapularis and R. microplus, and their cognate receptor only characterized for the last two. METHODS Expression of the periviscerokinin receptor (Rhimi-CAP2bR) was investigated throughout the developmental stages of R. microplus and silenced by RNA interference (RNAi) in the females. In a first experiment, three double-stranded (ds) RNAs, named ds680-805, ds956-1109 and ds1102-1200, respectively, were tested in vivo. All three caused phenotypic effects, but only the last one was chosen for subsequent experiments. Resulting RNAi phenotypic variables were compared to those of negative controls, both non-injected and dsRNA beta-lactamase-injected ticks, and to positive controls injected with beta-actin dsRNA. Rhimi-CAP2bR silencing was verified by quantitative reverse-transcriptase PCR in whole females and dissected tissues. RESULTS Rhimi-CAP2bR transcript expression was detected throughout all developmental stages. Rhimi-CAP2bR silencing was associated with increased female mortality, decreased weight of surviving females and of egg masses, a delayed egg incubation period and decreased egg hatching (P < 0.05). CONCLUSIONS CAP2b/PVKs appear to be associated with the regulation of female feeding, reproduction and survival. Since the Rhimi-CAP2bR loss of function was detrimental to females, the discovery of antagonistic molecules of the CAP2b/PVK signaling system should cause similar effects. Our results point to this signaling system as a promising target for tick control.
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Affiliation(s)
- Juan P. Wulff
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475 USA
| | - Kevin B. Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture–Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
| | - Jason P. Tidwell
- Cattle Fever Tick Research Laboratory, United States Department of Agriculture–Agricultural Research Service, 22675 N. Moorefield Rd. Building 6419, Edinburg, TX 78541-5033 USA
| | - Kristie G. Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture–Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
| | - Kimberly H. Lohmeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture–Agricultural Research Service, 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
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Kabi F, Dhikusooka M, Matovu M, Mugerwa S, Kasaija P, Emudong P, Kirunda H, Contreras M, Gortazar C, De la Fuente J. Monitoring the Subolesin Vaccine Field Trial for Safer Control of Cattle Ticks Amidst Increasing Acaricide Resistance in Uganda. Vaccines (Basel) 2022; 10:vaccines10101594. [PMID: 36298461 PMCID: PMC9609280 DOI: 10.3390/vaccines10101594] [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: 08/25/2022] [Revised: 09/20/2022] [Accepted: 09/20/2022] [Indexed: 11/22/2022] Open
Abstract
A collaboration program was established between the group of Health and Biotechnology (SaBio) of the IREC Institute of Game and Wildlife Research (CSIC-UCLM-JCCM, Spain) and the National Agricultural Research Organization of Uganda (NARO) for the development of vaccines for the control of cattle ticks in Uganda. Controlled pen trials identified a tick protective antigen, Rhipicephalus appendiculatus Subolesin, and a cross-species-effective vaccine formulation. As the next step, a controlled vaccine field trial has been approved by Ugandan state regulatory authorities, the Uganda National Council for Science and Technology (UNCST) and the National Drug Authority (NDA), to evaluate the efficacy and effectiveness of the vaccine formulation for the control of cattle tick infestations under field conditions. The results of this trial may lead to the approval of the vaccine for application in Uganda to improve cattle health and production while reducing the use of acaricides.
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Affiliation(s)
- Fredrick Kabi
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
| | - Moses Dhikusooka
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
| | - Moses Matovu
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
| | - Swidiq Mugerwa
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
| | - Paul Kasaija
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC), Consejo Superior de Investigaciones Cientí ficas (CSIC), Universidad de Castilla-La Mancha (UCLM)-Junta de Comunidades de Castilla-La Mancha (JCCM), Ronda de Toledo 12, 13005 Ciudad Real, Spain
| | - Patrick Emudong
- National Livestock Resources Research Institute (NaLIRRI/NARO), Kampala P.O. Box 5704, Uganda
| | - Halid Kirunda
- Mbarara Zonal Agricultural Research and Development Institute (MbaZARDI), Mbarara City P.O. Box 389, Uganda
| | - Marinela Contreras
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC), Consejo Superior de Investigaciones Cientí ficas (CSIC), Universidad de Castilla-La Mancha (UCLM)-Junta de Comunidades de Castilla-La Mancha (JCCM), Ronda de Toledo 12, 13005 Ciudad Real, Spain
| | - Christian Gortazar
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC), Consejo Superior de Investigaciones Cientí ficas (CSIC), Universidad de Castilla-La Mancha (UCLM)-Junta de Comunidades de Castilla-La Mancha (JCCM), Ronda de Toledo 12, 13005 Ciudad Real, Spain
| | - Jose De la Fuente
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC), Consejo Superior de Investigaciones Cientí ficas (CSIC), Universidad de Castilla-La Mancha (UCLM)-Junta de Comunidades de Castilla-La Mancha (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
- Correspondence: or
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The Correlation between Subolesin-Reactive Epitopes and Vaccine Efficacy. Vaccines (Basel) 2022; 10:vaccines10081327. [PMID: 36016215 PMCID: PMC9414912 DOI: 10.3390/vaccines10081327] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/10/2022] [Accepted: 08/14/2022] [Indexed: 11/16/2022] Open
Abstract
Vaccination is an environmentally-friendly alternative for tick control. The tick antigen Subolesin (SUB) has shown protection in vaccines for the control of multiple tick species in cattle. Additionally, recent approaches in quantum vaccinomics have predicted SUB-protective epitopes and the peptide sequences involved in protein−protein interactions in this tick antigen. Therefore, the identification of B-cell−reactive epitopes by epitope mapping using a SUB peptide array could be essential as a novel strategy for vaccine development. Subolesin can be used as a model to evaluate the effectiveness of these approaches for the identification of protective epitopes related to vaccine protection and efficacy. In this study, the mapping of B-cell linear epitopes of SUB from three different tick species common in Uganda (Rhipicephalus appendiculatus, R. decoloratus, and Amblyomma variegatum) was conducted using serum samples from two cattle breeds immunized with SUB-based vaccines. The results showed that in cattle immunized with SUB from R. appendiculatus (SUBra) all the reactive peptides (Z-score > 2) recognized by IgG were also significant (Z-ratio > 1.96) when compared to the control group. Additionally, some of the reactive peptides recognized by IgG from the control group were also recognized in SUB cocktail−immunized groups. As a significant result, cattle groups that showed the highest vaccine efficacy were Bos indicus immunized with a SUB cocktail (92%), and crossbred cattle were immunized with SUBra (90%) against R. appendiculatus ticks; the IgG from these groups recognized overlapping epitopes from the peptide SPTGLSPGLSPVRDQPLFTFRQVGLICERMMKERESQIRDEYDHVLSAKLAEQYDTFVKFTYDQKRFEGATPSYLS (Z-ratio > 1.96), which partially corresponded to a Q38 peptide and the SUB protein interaction domain. These identified epitopes could be related to the protection and efficacy of the SUB-based vaccines, and new chimeras containing these protective epitopes could be designed using this new approach.
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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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Wulff JP, Temeyer KB, Tidwell JP, Schlechte KG, Xiong C, Lohmeyer KH, Pietrantonio PV. Pyrokinin receptor silencing in females of the southern cattle tick Rhipicephalus (Boophilus) microplus is associated with a reproductive fitness cost. Parasit Vectors 2022; 15:252. [PMID: 35818078 PMCID: PMC9272880 DOI: 10.1186/s13071-022-05349-w] [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: 02/22/2022] [Accepted: 05/28/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Rhipicephalus microplus is the vector of deadly cattle pathogens, especially Babesia spp., for which a recombinant vaccine is not available. Therefore, disease control depends on tick vector control. However, R. microplus populations worldwide have developed resistance to available acaricides, prompting the search for novel acaricide targets. G protein-coupled receptors (GPCRs) are involved in the regulation of many physiological processes and have been suggested as druggable targets for the control of arthropod vectors. Arthropod-specific signaling systems of small neuropeptides are being investigated for this purpose. The pyrokinin receptor (PKR) is a GPCR previously characterized in ticks. Myotropic activity of pyrokinins in feeding-related tissues of Rhipicephalus sanguineus and Ixodes scapularis was recently reported. METHODS The R. microplus pyrokinin receptor (Rhimi-PKR) was silenced through RNA interference (RNAi) in female ticks. To optimize RNAi, a dual-luciferase assay was applied to determine the silencing efficiency of two Rhimi-PKR double-stranded RNAs (dsRNA) prior to injecting dsRNA in ticks to be placed on cattle. Phenotypic variables of female ticks obtained at the endpoint of the RNAi experiment were compared to those of control female ticks (non-injected and beta-lactamase dsRNA-injected). Rhimi-PKR silencing was verified by quantitative reverse-transcriptase PCR in whole females and dissected tissues. RESULTS The Rhimi-PKR transcript was expressed in all developmental stages. Rhimi-PKR silencing was confirmed in whole ticks 4 days after injection, and in the tick carcass, ovary and synganglion 6 days after injection. Rhimi-PKR silencing was associated with an increased mortality and decreased weight of both surviving females and egg masses (P < 0.05). Delays in repletion, pre-oviposition and incubation periods were observed (P < 0.05). CONCLUSIONS Rhimi-PKR silencing negatively affected female reproductive fitness. The PKR appears to be directly or indirectly associated with the regulation of female feeding and/or reproductive output in R. microplus. Antagonists of the pyrokinin signaling system could be explored for tick control.
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Affiliation(s)
- Juan P. Wulff
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475 USA
| | - Kevin B. Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
| | - Jason P. Tidwell
- Cattle Fever Tick Research Laboratory, USDA-ARS, 22675 N. Moorefield Rd. Building 6419, Edinburg, TX 78541-5033 USA
| | - Kristie G. Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
| | - Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475 USA
| | - Kimberly H. Lohmeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
| | - Patricia V. Pietrantonio
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX 78028-9184 USA
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23
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Obaid MK, Islam N, Alouffi A, Khan AZ, da Silva Vaz I, Tanaka T, Ali A. Acaricides Resistance in Ticks: Selection, Diagnosis, Mechanisms, and Mitigation. Front Cell Infect Microbiol 2022; 12:941831. [PMID: 35873149 PMCID: PMC9299439 DOI: 10.3389/fcimb.2022.941831] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 06/02/2022] [Indexed: 11/13/2022] Open
Abstract
Ticks are blood-feeding ecto-parasites that have a cosmopolitan distribution in tropical and subtropical regions of the world. Ticks cause economic losses in the form of reduced blood, meat and dairy products, as well as pathogen transmission. Different acaricides such as organochlorines, organophosphates, formamidines (e.g. amitraz), synthetic pyrethroids, macrocyclic lactones, fipronil, and fluazuron are currently used sequentially or simultaneously to control tick infestations. Most acaricide treatments now face increasingly high chances of failure, due to the resistance selection in different tick populations against these drugs. Acaricide resistance in ticks can be developed in different ways, including amino acid substitutions that result in morphological changes in the acaricide target, metabolic detoxification, and reduced acaricide entry through the outer layer of the tick body. The current literature brings a plethora of information regarding the use of different acaricides for tick control, resistance selection, analysis of mutations in target sites, and resistance mitigation. Alternatives such as synergistic use of different acaricides, plant-derived phytochemicals, fungi as biological control agents, and anti-tick vaccines have been recommended to avoid and mitigate acaricide resistance. The purpose of this review was to summarize and discuss different acaricides applied for tick control, their mechanisms of action and resistance selection, genetic polymorphisms in their target molecules, as well as the approaches used for diagnosis and mitigation of acaricide resistance, specifically in Rhipicephalus microplus ticks.
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Affiliation(s)
| | - Nabila Islam
- Department of Chemistry, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Abdulaziz Alouffi
- King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | - Alam Zeb Khan
- Department of Pediatrics, Yale School of Medicine Yale University, New Haven, CT, United States
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia and Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Tetsuya Tanaka
- Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima, Japan
| | - Abid Ali
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, Pakistan
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Deblauwe I, De Wolf K, De Witte J, Schneider A, Verlé I, Vanslembrouck A, Smitz N, Demeulemeester J, Van Loo T, Dekoninck W, Krit M, Madder M, Müller R, Van Bortel W. From a long-distance threat to the invasion front: a review of the invasive Aedes mosquito species in Belgium between 2007 and 2020. Parasit Vectors 2022; 15:206. [PMID: 35698108 PMCID: PMC9195248 DOI: 10.1186/s13071-022-05303-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 04/26/2022] [Indexed: 11/10/2022] Open
Abstract
Invasive mosquito species (IMS) and their associated mosquito-borne diseases are emerging in Europe. In Belgium, the first detection of Aedes albopictus (Skuse 1894) occurred in 2000 and of Aedes japonicus japonicus (Theobald 1901) in 2002. Early detection and control of these IMS at points of entry (PoEs) are of paramount importance to slow down any possible establishment. This article reviews the introductions and establishments recorded of three IMS in Belgium based on published (2007-2014) and unpublished (2015-2020) data collected during several surveillance projects. In total, 52 PoEs were monitored at least once for the presence of IMS between 2007 and 2020. These included used tyre and lucky bamboo import companies, airports, ports, parking lots along highways, shelters for imported cutting plants, wholesale markets, industrial areas, recycling areas, cemeteries and an allotment garden at the country border with colonised areas. In general, monitoring was performed between April and November. Mosquitoes were captured with adult and oviposition traps as well as by larval sampling. Aedes albopictus was detected at ten PoEs, Ae. japonicus at three PoEs and Aedes koreicus (Edwards 1917) at two PoEs. The latter two species have established overwintering populations. The percentage of PoEs positive for Ae. albopictus increased significantly over years. Aedes albopictus is currently entering Belgium through lucky bamboo and used tyre trade and passive ground transport, while Ae. japonicus through used tyre trade and probably passive ground transport. In Belgium, the import through passive ground transport was first recorded in 2018 and its importance seems to be growing. Belgium is currently at the invasion front of Ae. albopictus and Ae. japonicus. The surveillance and control management actions at well-known PoEs associated to long-distance introductions are more straightforward than at less-defined PoEs associated with short-distance introductions from colonised areas. These latter PoEs represent a new challenge for IMS management in Belgium in the coming years. Aedes albopictus is expected to become established in Belgium in the coming years, hence increasing the likelihood of local arbovirus transmission. The implementation of a sustainable, structured and long-term IMS management programme, integrating active and passive entomological surveillance, vector control and Public Health surveillance is therefore pivotal.
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Affiliation(s)
- Isra Deblauwe
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Katrien De Wolf
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, Belgium
| | - Jacobus De Witte
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Anna Schneider
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Ingrid Verlé
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Adwine Vanslembrouck
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Nathalie Smitz
- Royal Museum for Central Africa (BopCo), Tervuren, Belgium
| | - Julie Demeulemeester
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | | | - Wouter Dekoninck
- Royal Belgian Institute of Natural Sciences (Scientific Heritage Service), Brussels, Belgium
| | - Meryam Krit
- The Unit of Eco-Modelling, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Maxime Madder
- Clinglobal, Tamarin, Mauritius
- Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort, South Africa
| | - Ruth Müller
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Wim Van Bortel
- The Unit of Entomology, Department Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Outbreak Research Team, Institute of Tropical Medicine, Antwerp, Belgium
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Ozelame KPC, Mattia MMC, Dedavid e Silva LA, Randall LM, Corvo I, Saporiti T, Seixas A, da Silva Vaz I, Alvarez G. Novel tick glutathione transferase inhibitors as promising acaricidal compounds. Ticks Tick Borne Dis 2022; 13:101970. [DOI: 10.1016/j.ttbdis.2022.101970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 01/21/2023]
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Sharma AK, Tiwari SS, Kumar S, Rawat AKS, Srivastava S, Ray D, Singh NK, Rawat SS, Sangwan AK, Ghosh S. Establishment of antitick efficacy of a phytoformulation prepared from Annona squamosa leaf extracts for the management of acaricide resistant tick infestations on cattle. Acta Trop 2022; 233:106463. [PMID: 35460645 DOI: 10.1016/j.actatropica.2022.106463] [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: 01/12/2022] [Revised: 04/08/2022] [Accepted: 04/10/2022] [Indexed: 11/18/2022]
Abstract
To combat the problem of acaricide resistance in ticks, efforts have been made to develop eco-friendly herbal acaricides which are safe for animal use with no possibilities of evoking environment and residual toxicity. In the present study, the acaricidal properties of a commonly available plant, Annona squamosa have been established to develop a novel antitick phytoformulation using leaf extract, suitable solvents and emulsifier for managing resistant tick infestations in animals. The quality control of the safe and stable phytoformulation using Rutin as a major constituent was maintained by HPTLC profiling. Several phytformulations (A-E) were prepared and formulation 'C' is identifried as the most effective showing 52.5-75% antitick activity against in vitro treated resistant strains of R. microplus (IVRI-IV and V) with 33.8-40.2% inhibition of oviposition while 65-85% mortality against multiacaricide resistant field populations. The phytoformulation provided 70.4% efficacy after first larval challenge in experimentally infested animals. The field efficacy of the formulation in different multilocational field trials was 68.53-77.8%. The detail antitick efficacy of the formulation along with safety and stability are explained as a component of antitck technology to manage resistant tick problem in livestock.
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Affiliation(s)
- Anil Kumar Sharma
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122 U.P. India
| | - Shashi Shankar Tiwari
- Pharmacognosy and Ethnopharmacology Division, CSIR-National Botanical Research Institute, Lucknow 226001 U.P., India
| | - Sachin Kumar
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122 U.P. India
| | - Ajay Kumar Singh Rawat
- Pharmacognosy and Ethnopharmacology Division, CSIR-National Botanical Research Institute, Lucknow 226001 U.P., India
| | - Sharad Srivastava
- Pharmacognosy and Ethnopharmacology Division, CSIR-National Botanical Research Institute, Lucknow 226001 U.P., India
| | - Debdatta Ray
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122 U.P. India
| | - Nirbhay Kumar Singh
- Department of Veterinary Parasitology, College of Veterinary Science, Guru Angad Dev Veterinary & Animal Sciences University, Ludhiana 141004 Punjab India
| | - Sumer Singh Rawat
- Department of Animals Husbandry, Govt. of Rajasthan, Chittorgarh 312001 Rajasthan, India
| | - Arun Kumar Sangwan
- Department of Veterinary Parasitology, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, 125004 Haryana, India
| | - Srikanta Ghosh
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243122 U.P. India.
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Integrative Alternative Tactics for Ixodid Control. INSECTS 2022; 13:insects13030302. [PMID: 35323601 PMCID: PMC8948879 DOI: 10.3390/insects13030302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 02/04/2023]
Abstract
Simple Summary Hard ticks are important for economic and health reasons, and control has mainly relied upon use of synthetic acaricides. Contemporary development of resistance and concerns relating to health and environmental safety have elicited exploration into alternative tactics for hard tick management. Some examples of alternative tactics involve biological control, desiccant dusts, growth regulators, vaccines, cultural methods, and ingested medications. Abstract Ixodids (hard ticks), ectoparasitic arthropods that vector the causal agents of many serious diseases of humans, domestic animals, and wildlife, have become increasingly difficult to control because of the development of resistance against commonly applied synthetic chemical-based acaricides. Resistance has prompted searches for alternative, nonconventional control tactics that can be used as part of integrated ixodid management strategies and for mitigating resistance to conventional acaricides. The quest for alternative control tactics has involved research on various techniques, each influenced by many factors, that have achieved different degrees of success. Alternative approaches include cultural practices, ingested and injected medications, biological control, animal- and plant-based substances, growth regulators, and inert desiccant dusts. Research on biological control of ixodids has mainly focused on predators, parasitoid wasps, infective nematodes, and pathogenic bacteria and fungi. Studies on animal-based substances have been relatively limited, but research on botanicals has been extensive, including whole plant, extract, and essential oil effects on ixodid mortality, behavior, and reproduction. The inert dusts kaolin, silica gel, perlite, and diatomaceous earth are lethal to ixodids, and they are impervious to environmental degradation, unlike chemical-based toxins, remaining effective until physically removed.
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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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Dzemo WD, Thekisoe O, Vudriko P. Development of acaricide resistance in tick populations of cattle: A systematic review and meta-analysis. Heliyon 2022; 8:e08718. [PMID: 35059516 PMCID: PMC8760414 DOI: 10.1016/j.heliyon.2022.e08718] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 10/25/2021] [Accepted: 01/04/2022] [Indexed: 12/27/2022] Open
Abstract
The development of acaricide resistance in ticks infesting cattle is a major problem in the livestock industry in tropical and subtropical regions worldwide. To determine the current global trends and prevalence of acaricide resistance development (ARD) in tick populations of cattle, a systematic review and meta-analysis with an emphasis on Rhipicephalus (Boophilus) microplus was conducted. Data searches from five English electronic databases yielded 88 journal articles published between 1992 and 2020. In total, 218 in - vitro bioassays were used to investigate 3939 tick populations of cattle; of these, the 57.6% that exhibited ARD were largely limited to South America (Brazil), Central America (Mexico), and Asia (India). A total of 3391 of these tick populations were R. (B.) microplus, of which 2013 exhibited ARD. Random effects meta-analyses indicated that the exhibition of ARD was higher in R. (B.) microplus (66.2%) than in other tick species. Global prevalence estimates of ARD in R. (B.) microplus vary as a function of geography, detection methods, and acaricide compounds. In general, high heterogeneity was noted among the studies. However, homogeneity was observed among studies from India, suggesting the establishment of acaricide resistance in Indian R. (B.) microplus populations. Current tick control interventions are urgently required to limit the evolution and implications of resistance development.
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Affiliation(s)
- William Diymba Dzemo
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University, Private Bag X1, Mthatha 5117, South Africa.,Unit for Environmental Sciences and Management, North West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, 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, P.O Box 7062, Kampala, Uganda
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Githaka NW, Kanduma EG, Wieland B, Darghouth MA, Bishop RP. Acaricide resistance in livestock ticks infesting cattle in Africa: Current status and potential mitigation strategies. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2022; 2:100090. [PMID: 35664895 PMCID: PMC9160480 DOI: 10.1016/j.crpvbd.2022.100090] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 04/10/2022] [Accepted: 05/07/2022] [Indexed: 11/19/2022]
Abstract
In many African countries, tick control has recently been the responsibility of resource-poor farmers rather than central government veterinary departments. This has led to an increase in acaricide resistance, threatening the welfare of livestock farmers in sub-Saharan Africa. Resistance has evolved to the three classes of acaricides used most extensively in the continent, namely fourth-generation synthetic pyrethroids (SP), organophosphates (OP) and amidines (AM), in virtually all countries in which they have been deployed across the globe. Most current data are derived from research in Australia and Latin America, with the majority of studies on acaricide resistance in Africa performed in South Africa. There is also limited recent research from West Africa and Uganda. These studies confirm that acaricide resistance in cattle ticks is a major problem in Africa. Resistance is most frequently directly assayed in ticks using the larval packet test (LPT) that is endorsed by FAO, but such tests require a specialist tick-rearing laboratory and are relatively time consuming. To date they have only been used on a limited scale in Africa and resistance is often still inferred from tick numbers on animals. Rapid tests for resistance in ticks, would be better than the LPT and are theoretically possible to develop. However, these are not yet available. Resistance can be mitigated through integrated control strategies, comprising a combination of methods, including acaricide class rotation or co-formulations, ethnoveterinary practices, vaccination against ticks and modified land management use by cattle, with the goal of minimising the number of acaricide applications required per year. There are data suggesting that small-scale farmers in Africa are often unaware of the chemical differences between different acaricide brands and use these products at concentrations other than those recommended by the manufacturers, or in incorrect rotations or combinations of the different classes of chemicals on the market. There is an urgent need for a more evidence-based approach to acaricide usage in small-scale livestock systems in Africa, including direct measurements of resistance levels, combined with better education of farmers regarding acaricide products and how they should be deployed for control of livestock ticks. Resistance to all fourth-generation acaricides is widespread in cattle ticks and is a major problem in Africa. Acaricide resistance monitoring through the larval packet tests is mostly absent. The integration of ethnoveterinary products with synthetic acaricides is a promising strategy. Strengthening laboratory testing and farmersʼ education can lead to rational acaricide use.
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Affiliation(s)
- Naftaly W. Githaka
- International Livestock Research Institute (ILRI), P.O. Box 30709-00100, Nairobi, Kenya
- Corresponding author. Twitter icon
| | - Esther G. Kanduma
- Department of Biochemistry, Faculty of Science and Technology, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya
| | - Barbara Wieland
- International Livestock Research Institute (ILRI), P.O. Box 30709-00100, Nairobi, Kenya
| | - Mohamed A. Darghouth
- Laboratoire de Parasitologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de lʼEnseignement Supérieur Agricoles and La Manouba University, 2020, Sidi Thabet, Tunisia
| | - Richard P. Bishop
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA
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Molecular survey of cattle ticks in Burundi: First report on the presence of the invasive Rhipicephalus microplus tick. PLoS One 2021; 16:e0261218. [PMID: 34890445 PMCID: PMC8664164 DOI: 10.1371/journal.pone.0261218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/27/2021] [Indexed: 12/04/2022] Open
Abstract
A recent research study on prevalence of tick-borne pathogens in Burundi reported high prevalence and endemicity of Theileria parva, Anaplasma marginale and Babesia bigemina infections in cattle. Detailed information about tick species infesting animals, their distribution and genetic diversity in Burundi is outdated and limited. This study therefore assessed the prevalence and genetic diversity of tick species infesting cattle across agroecological zones (AEZs) in Burundi. A cross-sectional study on the occurrence of tick species was conducted in 24 districts of Burundi between October and December 2017. Differential identification and characterization of ticks collected was conducted using tick morphological keys and molecular tools (cox1 and 12S rRNA gene). Chi-square test was used to test for association between agroecological zones and the prevalence of tick species. Phylogenetic relationships were inferred using bayesian and maximum likelihood algorithms. A total of 483 ticks were collected from the five AEZs sampled. Six tick species comprising of Rhipicephalus appendiculatus, R. sanguineus, R. evertsi evertsi, R. microplus, R. decoloratus and Amblyomma variegatum were observed. Rhipicephalus appendiculatus were the most prevalent ticks (~45%). A total of 138 specimens (28%) were found to be Rhipicephalus microplus, suggesting an emerging threat for cattle farmers. Twelve R. appendiculatus cox1 haplotypes were obtained from 106 specimens that were sequenced. Two cox1 haplotypes of R. microplus which clustered into previously reported Clade A were observed. Rhipicephalus sanguineus and R. evertsi evertsi ticks, the vectors of numerous zoonotic pathogens, were collected from cattle, which constitute a high risk for public health. These findings reveal an overlapping distribution of tick vectors in Burundi. The design of ticks and tick-borne diseases control strategies should consider the distribution of different vectors across the AEZs particularly the presence of the highly invasive R. microplus tick in Burundi and the potential risk of introducing the pathogenic Babesia bovis.
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Allan FK, Sindoya E, Adam KE, Byamungu M, Lea RS, Lord JS, Mbata G, Paxton E, Mramba F, Torr SJ, Morrison WI, Handel I, Morrison LJ, Auty HK. A cross-sectional survey to establish Theileria parva prevalence and vector control at the wildlife-livestock interface, Northern Tanzania. Prev Vet Med 2021; 196:105491. [PMID: 34562810 PMCID: PMC8573586 DOI: 10.1016/j.prevetmed.2021.105491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 09/02/2021] [Accepted: 09/09/2021] [Indexed: 11/28/2022]
Abstract
East Coast fever (ECF) in cattle is caused by the protozoan parasite Theileria parva, transmitted by Rhipicephalus appendiculatus ticks. In cattle ECF is often fatal, causing annual losses >$500 million across its range. The African buffalo (Syncerus caffer) is the natural host for T. parva but the transmission dynamics between wild hosts and livestock are poorly understood. This study aimed to determine the prevalence of T. parva in cattle, in a 30 km zone adjacent to the Serengeti National Park, Tanzania where livestock and buffalo co-exist, and to ascertain how livestock keepers controlled ECF and other vector-borne diseases of cattle. A randomised cross-sectional cattle survey and questionnaire of vector control practices were conducted. Blood samples were collected from 770 cattle from 48 herds and analysed by PCR to establish T. parva prevalence. Half body tick counts were recorded on every animal. Farmers were interviewed (n = 120; including the blood sampled herds) using a standardised questionnaire to obtain data on vector control practices. Local workshops were held to discuss findings and validate results. Overall prevalence of T. parva in cattle was 5.07% (CI: 3.70-7.00%), with significantly higher prevalence in older animals. Although all farmers reported seeing ticks on their cattle, tick counts were very low with 78% cattle having none. Questionnaire analysis indicated significant acaricide use with 79% and 41% of farmers reporting spraying or dipping with cypermethrin-based insecticides, respectively. Some farmers reported very frequent spraying, as often as every four days. However, doses per animal were often insufficient. These data indicate high levels of acaricide use, which may be responsible for the low observed tick burdens and low ECF prevalence. This vector control is farmer-led and aimed at both tick- and tsetse-borne diseases of livestock. The levels of acaricide use raise concerns regarding sustainability; resistance development is a risk, particularly in ticks. Integrating vaccination as part of this community-based disease control may alleviate acaricide dependence, but increased understanding of the Theileria strains circulating in wildlife-livestock interface areas is required to establish the potential benefits of vaccination.
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Affiliation(s)
- Fiona K Allan
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom.
| | - Emmanuel Sindoya
- Minstry of Livestock and Fisheries, Serengeti District Livestock Office, Mugumu, Tanzania
| | - Katherine E Adam
- Innogen Institute, Science Technology and Innovation Studies; School of Social and Political Science, University of Edinburgh, Old Surgeons' Hall, High School Yards, Edinburgh, United Kingdom
| | | | - Rachel S Lea
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jennifer S Lord
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Geofrey Mbata
- Vector and Vector-borne Diseases Research Institute, Tanga, Tanzania
| | - Edith Paxton
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Furaha Mramba
- Tanzania Veterinary Laboratory Agency, Dar es Salaam, Tanzania
| | - Stephen J Torr
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - W Ivan Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Ian Handel
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Liam J Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Harriet K Auty
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, United Kingdom (Previously Epidemiology Research Unit, SRUC, Inverness, United Kingdom)
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Shyma KP, Gupta JP, Parsani HR, Ankuya KJ, Singh V. Ivermectin resistance in the multi-host tick Hyalomma anatolicum (Acari: Ixodidae) in India. Ticks Tick Borne Dis 2021; 12:101791. [PMID: 34329928 DOI: 10.1016/j.ttbdis.2021.101791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 07/02/2021] [Accepted: 07/02/2021] [Indexed: 11/18/2022]
Abstract
The multi-host tick, Hyalomma anatolicum is a widely distributed vector of many pathogens of veterinary and public health importance. Ivermectin (IVM), as an alternative to control pyrethroid-resistant ticks, has been used extensively for the past 4-6 years in tropical and sub-tropical countries including India resulting in declining tick control efficacy. The present study used adult immersion test (AIT) to examine the resistance status of H. anatolicum collected from three districts in the Indian state of Gujarat against ivermectin. Probit analysis was used for calculation of concentration-mortality regressions; concentrations required for 50% mortality (LC50) and 95% mortality (LC95), along with confidence intervals; slope of mortality; % inhibition of oviposition; and discriminating concentration (DC). The calculated LC50 and LC95 estimates were utilized to determine resistance ratios (RR50, RR95) and the resistance levels (RL) of the field ticks compared to the susceptible population. The DC (2 x LC95) for IVM was calculated as 84.48 ppm, using susceptible H. anatolicum ticks (KHD). Lower estimates of the coefficient of non-determination (1-R2) for AIT ranged from 0.06 to 0.27, and the range of RR50 and RR95 values against IVM was estimated to be from 1.43 to 52.06 and 1.14 to 71.99, respectively, which indicated a varying degree of resistance among the field tick populations. Based on RR50 values, tick populations from Danta and Palanpur showed resistance level IV and II, respectively. Another four populations (Vadgam, Kankrej, Saraswati and Sidhpur) were classified as having level I resistance status against IVM. To our knowledge, this is the first report of ivermectin resistance in H. anatolicum from Gujarat, India.
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Affiliation(s)
- K P Shyma
- Department of Veterinary Parasitology, College of Veterinary Science & AH, Kamdhenu University (Erstwhile SDAU), Sardarkrushinagar, 385506 Gujarat (India).
| | - Jay Prakash Gupta
- Department of Animal Genetics & Breeding, College of Veterinary Science & AH, Kamdhenu University (Erstwhile SDAU), Sardarkrushinagar, 385506 Gujarat (India).
| | - H R Parsani
- Department of Veterinary Parasitology, College of Veterinary Science & AH, Kamdhenu University (Erstwhile SDAU), Sardarkrushinagar, 385506 Gujarat (India).
| | - K J Ankuya
- Department of Livestock Production & Management, College of Veterinary Science & AH, Kamdhenu University (Erstwhile SDAU), Sardarkrushinagar, 385506 Gujarat (India).
| | - Veer Singh
- Department of Veterinary Parasitology, College of Veterinary Science & AH, Kamdhenu University (Erstwhile SDAU), Sardarkrushinagar, 385506 Gujarat (India); Director Resident Instruction-cum-Dean, Post Graduate Studies, BASU, Patna, 800 014, Bihar (India).
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Molecular detection of selected tick-borne pathogens infecting cattle at the wildlife-livestock interface of Queen Elizabeth National Park in Kasese District, Uganda. Ticks Tick Borne Dis 2021; 12:101772. [PMID: 34214889 DOI: 10.1016/j.ttbdis.2021.101772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/19/2021] [Accepted: 06/03/2021] [Indexed: 11/22/2022]
Abstract
In Uganda, ticks and tick-borne diseases (TBDs) pose a big challenge to farmers. They reduce cattle productivity and cause severe economic damage. Several studies have documented the prevalence of tick-borne pathogens in cattle; however, their genetic characteristics and the role of wildlife-livestock interaction in the epidemiology of the TBDs are not well documented. This study assessed the prevalence and genetic diversity of various tick-borne pathogens (TBPs) as well as the risk factors associated with the occurrence of TBPs in blood samples of 208 randomly selected cattle from 16 farms located around Queen Elizabeth National Park (QENP) in Kasese District in western Uganda. Farming practices, disease challenges, and the level of wildlife-livestock interactions were assessed by a questionnaire survey amongst farm owners. Polymerase chain reaction (PCR) assays revealed that 62.9% (131/208) cattle samples were positive for one or more pathogens. Using specific PCR assays, we detected Theileria spp., Theileria parva, Anaplasma marginale, Anaplasma platys-like, and Babesia bigemina at 50.5%, 27.9%, 19.2%, 11.5% and 8.7%, respectively. We also confirmed the infection of samples by Theileria velifera and Theileria mutans after sequencing the Theileria spp. 18S rRNA gene. The risk factors associated with the occurrence of TBPs included communal grazing, herd size, age, and proximity to QENP. Phylogenetic analysis of the T. parva p104 gene showed a high identity to the previous isolates from Uganda and other East African countries and clustered closer to the buffalo (Syncerus caffer) isolates, suggesting a possible cross-species transmission. The sequences of A. marginale groEL and B. bigemina RAP-1a formed well-supported clades with high identities to the previous isolates identified from central and eastern Uganda. The isolates obtained from A. phagocytophilum 16S rRNA gene sequences showed relationship with A. platys-like, Anaplasma sp., uncultured Anaplasma species and A. phagocytophilum isolates from Africa, Asia, Europe, and the USA. The findings of the present study showed that TBDs are still a burden to farmers and that management practices in this area may increase the transmission of pathogens between livestock and wildlife.
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Cattle ticks and tick-borne diseases: a review of Uganda's situation. Ticks Tick Borne Dis 2021; 12:101756. [PMID: 34134062 DOI: 10.1016/j.ttbdis.2021.101756] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/14/2021] [Accepted: 05/24/2021] [Indexed: 02/06/2023]
Abstract
Herein we review the epidemiology of ticks and tick-borne diseases (TTBDs), their impact on livestock health and on the economy, control and associated challenges in Uganda. Ticks are leading vectors of economically important pathogens and are widespread in Uganda due to suitable climatic conditions. Besides the physical injury inflicted on the animal host, ticks transmit a number of pathogens that can cause morbidity and mortality of livestock if untreated, resulting in economic losses. Uganda suffers an aggregated annual loss (direct and indirect) of over USD 1.1 billion in the TTBDs complex. East Coast fever (ECF) caused by a protozoan haemoparasite, Theileria parva, is the most prevalent and economically important tick-borne disease (TBD) in Uganda and its vector, the brown ear tick (Rhipicephalus appendiculatus) widely distributed. Other prevalent TBDs in Uganda include anaplasmosis, babesiosis and heartwater. We highlight the role of agro-ecological zones (AEZs) and livestock management system in the distribution of TTBDs, citing warm and humid lowlands as being ideal habitats for ticks and endemic for TBDs. Control of TTBDs is a matter of great importance as far as animal health is concerned in Uganda. Indigenous cattle, which make up over 90% of the national herd are known to be more tolerant to TTBDs and most farms rely on endemic stability to TBDs for control. However, exotic cattle breeds are more capital intensive than indigenous breeds, but the increasing adoption of tick-susceptible exotic cattle breeds (especially dairy) in western and central Uganda demands intensive use of acaricides for tick control and prevention of TBDs. Such acaricide pressure has unfortunately led to selection of acaricide-resistant tick populations and the consequent acaricide resistance observed in the field. Vaccination against ECF, selective breeding for tick resistance and integrated tick control approaches that limit tick exposure, could be adopted to interrupt spread of acaricide resistance. We recommend increasing monitoring and surveillance for TTBDs and for emerging acaricide resistance, improved extension services and sensitization of farmers on tick control measures, appropriate acaricide use and the development and implementation of vaccines for the control of TTBDs as more sustainable and effective interventions. A tick control policy should be developed, taking into account variations of agro-ecological zones, farm circumstances and indigenous technical knowledge, and this should be incorporated into the overall animal health program.
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Mutavi F, Heitkönig I, Wieland B, Aarts N, Van Paassen A. Tick treatment practices in the field: Access to, knowledge about, and on-farm use of acaricides in Laikipia, Kenya. Ticks Tick Borne Dis 2021; 12:101757. [PMID: 34147920 DOI: 10.1016/j.ttbdis.2021.101757] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 11/19/2022]
Abstract
The prevention of tick-borne diseases is a major challenge for livestock production globally. Tick control strategies include the use of acaricides, but the prescribed strategies do not achieve the desired results in several countries, including Kenya. To better understand how tick treatment practices, contribute to reported tick treatment failures, we assessed livestock owners' acaricide procurement, level of knowledge about acaricides and tick resistance, and how they apply acaricides. We also assessed the quality of the commonly available acaricides. We focused on three livestock systems in Laikipia County, Kenya: two private ranches; one community ranch whose members communally graze their cattle and acquire and apply acaricides; and individual livestock owners in two pastoral communities who individually graze their cattle and acquire and apply acaricides. Through interviews and focus group discussions we assessed; access to acaricides, livestock owners' knowledge, and acaricide use practices; interview data were triangulated with participant observations (n = 107). We analysed nine commonly used acaricides to determine the active ingredient concentration and we determined the concentration of active ingredients in acaricide dilutions collected on farms. All livestock owners had access to and used chemical acaricides for tick control, predominantly amitraz-based. Private ranchers bought one amitraz-based acaricide in bulk directly from the manufacturer, while all other livestock owners bought from agrovet shops. The livestock owners acquired knowledge about acaricides from their own experiences and through experience-based recommendations from peers, but not from the technical information provided by the manufacturers and agrovet shops. All pastoral livestock frequently changed acaricide brand and active ingredient class. A large majority of pastoralists (86%) mixed acaricide brands within and across active ingredient classes; a smaller majority (56%) mixed acaricides with crop pesticides and insecticides. Our lab tests confirmed the content description on the labels bought from agrovet shops. However, on-farm acaricide dilutions from all three livestock systems deviated from the level recommended for effective treatment. If too diluted, the acaricide does not kill ticks, promoting resistance development. If too concentrated, this increases environmental contamination and raises public health concerns. Livestock owners lack a technical understanding of the functioning of acaricides, compromising their use and effectiveness. The widely adopted mixing of acaricides with insecticides and pesticides raises serious health concerns.
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Affiliation(s)
- Faith Mutavi
- Strategic Communication Group, Wageningen University, P.O. Box 8130-6700 EW Wageningen, the Netherlands; Wildlife Ecology and Conservation Group, Wageningen University, PO Box 47-6700AA Wageningen, the Netherlands; International Livestock Research Institute, PO Box 30709-00100, Nairobi, Kenya.
| | - Ignas Heitkönig
- Wildlife Ecology and Conservation Group, Wageningen University, PO Box 47-6700AA Wageningen, the Netherlands
| | - Barbara Wieland
- International Livestock Research Institute, PO Box 5689 Addis Ababa, Ethiopia; Institute of Virology and Immunology, P.O Box 3350 - 3001 Bern Mittelhäusern, Switzerland; Department of Infectious Diseases and Pathobiology (DIP), Vetsuisse Faculty, University of Bern, P.O Box 3350 - 3001 Bern Mittelhäusern, Switzerland
| | - Noelle Aarts
- Strategic Communication Group, Wageningen University, P.O. Box 8130-6700 EW Wageningen, the Netherlands; Institute for Science in Society, Radboud University, Faculty of Science, P.O. Box 9010, 6500 GL Nijmegen, the Netherlands
| | - Annemarie Van Paassen
- Knowledge, Technology and Innovation Group, Wageningen University, P.O. Box 8130-6700 EW Wageningen, the Netherlands
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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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Sporadic outbreaks of crimean-congo haemorrhagic fever in Uganda, July 2018-January 2019. PLoS Negl Trop Dis 2021; 15:e0009213. [PMID: 33684124 PMCID: PMC7971858 DOI: 10.1371/journal.pntd.0009213] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 03/18/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Introduction Crimean-Congo haemorrhagic fever (CCHF) is a tick-borne, zoonotic viral disease that causes haemorrhagic symptoms. Despite having eight confirmed outbreaks between 2013 and 2017, all within Uganda’s ‘cattle corridor’, no targeted tick control programs exist in Uganda to prevent disease. During a seven-month-period from July 2018-January 2019, the Ministry of Health confirmed multiple independent CCHF outbreaks. We investigated to identify risk factors and recommend interventions to prevent future outbreaks. Methods We defined a confirmed case as sudden onset of fever (≥37.5°C) with ≥4 of the following signs and symptoms: anorexia, vomiting, diarrhoea, headache, abdominal pain, joint pain, or sudden unexplained bleeding in a resident of the affected districts who tested positive for Crimean-Congo haemorrhagic fever virus (CCHFv) by RT-PCR from 1 July 2018–30 January 2019. We reviewed medical records and performed active case-finding. We conducted a case-control study and compared exposures of case-patients with age-, sex-, and sub-county-matched control-persons (1:4). Results We identified 14 confirmed cases (64% males) with five deaths (case-fatality rate: 36%) from 11 districts in western and central region. Of these, eight (73%) case-patients resided in Uganda’s ‘cattle corridor’. One outbreak involved two case-patients and the remainder involved one. All case-patients had fever and 93% had unexplained bleeding. Case-patients were aged 6–36 years, with persons aged 20–44 years more affected (AR: 7.2/1,000,000) than persons ≤19 years (2.0/1,000,000), p = 0.015. Most (93%) case-patients had contact with livestock ≤2 weeks before symptom onset. Twelve (86%) lived <1 km from grazing fields compared with 27 (48%) controls (ORM-H = 18, 95% CI = 3.2-∞) and 10 (71%) of 14 case-patients found ticks attached to their bodies ≤2 weeks before symptom onset, compared to 15 (27%) of 56 control-persons (ORM-H = 9.3, 95%CI = 1.9–46). Conclusions CCHF outbreaks occurred sporadically during 2018–2019, both within and outside ‘cattle corridor’ districts of Uganda. Most cases were associated with tick exposure. The Ministry of Health should partner with the Ministry of Agriculture, Animal Industry and Fisheries to develop joint nationwide tick control programs and strategies with shared responsibilities through a One Health approach. Uganda has had multiple Crimean-Congo haemorrhagic fever outbreaks since 2013 when the first outbreak was confirmed. Tick exposure has been identified as the major risk factor by our study and this finding was similar with other studies done during outbreaks in Uganda. However, Uganda still lacks national tick control guidelines and indiscriminate use of acaricides (pesticides specially for ticks) has been observed widely. This has been cited to influence increased tick resistance to acaricides. Our study might not indicate whether tick resistance to acaricides has increased tick populations in Uganda however it is imperative that tick control is considered in efforts of prevention and control of CCHF outbreaks. We therefore recommend improved tick control in Uganda through national regulations on acaricide distribution and use, development of strategies to reduce tick resistance to acaricides in the country, and more community-based engagement of tick control in livestock management.
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Alota SL, Edquiban TRJ, Galay RL, Bernardo JMG, Sandalo KAC, Divina BP, Tanaka T. Determination of resistance status to amitraz in the cattle tick Rhipicephalus (Boophilus) microplus from Luzon, Philippines, through bioassay and molecular analysis. EXPERIMENTAL & APPLIED ACAROLOGY 2021; 83:399-409. [PMID: 33590359 DOI: 10.1007/s10493-021-00593-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 01/23/2021] [Indexed: 06/12/2023]
Abstract
Tick infestations and tick-borne diseases are among the leading causes of economic losses in the cattle industry worldwide. Amitraz is one of the most commonly used chemical acaricides against the cattle tick Rhipicephalus (Boophilus) microplus. Resistance to amitraz has been reported in many countries but not in the Philippines. This study aimed to determine whether cattle ticks from provinces in northern and southern Luzon, Philippines, are resistant to amitraz. Engorged or nearly engorged female ticks were collected from 21 farms and allowed to lay eggs to produce larvae. Larval packet test (LPT) was performed using three concentrations of amitraz, as well as a negative control (diluent). Reverse-transcription polymerase chain reaction (RT-PCR) was also performed to amplify a fragment of the octopamine/tyramine receptor gene and was subjected to sequence analysis by multiple nucleotide and amino acid sequence alignments together with reference strain, amitraz-susceptible strain, and amitraz-resistant strain reported in other countries. LPT results suggest the absence of resistance in all of the tested populations. Interestingly, analysis of the octopamine/tyramine receptor amino acid sequence revealed four out of 14 larval pools having substitutions similar to that of the reported amitraz-resistant strains. Although no apparent resistance was observed in this study, prudent use of amitraz should be practiced as the development of resistance is still likely to occur in the future.
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Affiliation(s)
- Sherwin L Alota
- School of Veterinary Medicine, Isabela State University-Echague, 3309, Echague, Isabela, Philippines
| | - Tisha Rogelle J Edquiban
- Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, 4031, Los Baños, Laguna, Philippines
| | - Remil L Galay
- Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, 4031, Los Baños, Laguna, Philippines.
| | - John Michael G Bernardo
- Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, 4031, Los Baños, Laguna, Philippines
| | - Kristina Andrea C Sandalo
- Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, 4031, Los Baños, Laguna, Philippines
| | - Billy P Divina
- Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, 4031, Los Baños, Laguna, Philippines
| | - Tetsuya Tanaka
- Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Korimoto, Kagoshima, 890-0065, Japan
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Lubembe DM, Odongo DO, Joubert F, Sibeko-Matjila KP. Limited diversity in the CD8+ antigen-coding loci in Theileria parva parasites from cattle from southern and eastern Africa. Vet Parasitol 2021; 291:109371. [PMID: 33621717 DOI: 10.1016/j.vetpar.2021.109371] [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: 08/01/2020] [Accepted: 01/23/2021] [Indexed: 11/17/2022]
Abstract
Theileria parva infections in cattle causes huge economic losses in the affected African countries, directly impacting the livelihood of the poor small-holder farmers. The current immunization protocol using live sporozoites in eastern Africa, is among the control measures designed to limit T. parva infections in cattle. However, the ability of the immune protection induced by this immunization to protect against field parasites has been compromised by the diversity of the parasite involving the schizont antigen genes. Previous studies have reported on the antigenic diversity of T. parva parasites from southern and eastern Africa, however, similar reports on T. parva parasites particularly from cattle from southern Africa remains scanty, due to the self-limiting nature of Corridor disease. Thus, we evaluated the diversity of CD8+ T-cell regions of ten schizont antigen genes in T. parva parasites associated with Corridor disease and East Coast fever (ECF) from southern and eastern Africa respectively. Regions of schizont antigen (TpAg) genes containing the CD8+ T-cell epitopes (CTL determinants) were amplified from genomic DNA extracted from blood of T. parva positive samples, cloned and sequenced. The results revealed limited diversity between the two parasite groups from cattle from southern and eastern Africa, defying the widely accepted notion that antigen-encoding loci in cattle-derived parasites are conserved, while in buffalo-derived parasites, they are extensively variable. This suggests that only a sub-population of parasites is successfully transmitted from buffalo to cattle, resulting in the limited antigenic diversity in Corridor disease parasites. Tp4, Tp5, Tp7 and Tp8 showed limited to absence of diversity in both parasite groups, suggesting the need to further investigate their immunogenic properties for consideration as candidates for a subunit vaccine. Distinct and common variants of Tp2 were detected among the ECF parasites from eastern Africa indicating evidence of parasite mixing following immunization. This study provides additional information on the comparative diversity of TpAg genes in buffalo- and cattle-derived T. parva parasites from cattle from southern and eastern Africa.
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Affiliation(s)
- Donald M Lubembe
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, South Africa.
| | - David O Odongo
- School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - Fourie Joubert
- Centre for Bioinformatics and Computational Biology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Hatfield, South Africa
| | - Kgomotso P Sibeko-Matjila
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, South Africa
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Geographic distribution of boophilid ticks in communal grazing cattle in the north-eastern region of the Eastern Cape Province, South Africa. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2021; 23:100538. [PMID: 33678391 DOI: 10.1016/j.vprsr.2021.100538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/16/2021] [Accepted: 01/18/2021] [Indexed: 11/22/2022]
Abstract
The boophilid ticks are regarded as highly adaptive tick species in tropical and subtropical regions and considered to be the most economically important ectoparasites to cattle worldwide. To that, a geographical survey to investigate the distribution of boophilid ticks on grazing cattle was conducted seasonally between October 2018 and September 2019 at Elundini, Senqu and Walter Sisulu Local Municipalities in the north-eastern region of the Eastern Cape Province (ECP). Ten cattle were selected randomly during the tick sampling at each locality. Ticks were carefully removed from cattle and placed into sampling tubes containing 70% ethanol. During tick sampling, special attention was paid to the tick predilection sites such as lower perineum, neck, dewlap and ventral body parts which are the preferred sites for blue ticks. Based on the morphological traits, a total of 6176 ticks belonging to two boophilid tick species of Rhipicephalus were identified: Rhipicephalus decoloratus (98.30%) and Rhipicephalus microplus (1.70%). Locality and season significantly influenced boophilid tick distribution (P < 0.05). Rhipicephalus decoloratus had a significantly higher prevalence (P < 0.05) in Elundini during the hot-dry (3.37 ± 0.121) and hot-wet (3.35 ± 0.121) seasons compared to other localities. In Senqu, R. microplus had high counts (P < 0.05) during the post-rainy season (1.06 ± 0027) compared to other localities. Interestingly, the current study recorded Asiatic invasive pantropical blue tick (R. microplus) for the first time in the north-eastern region of the ECP. This tick is of great veterinary economic importance locally and globally, and thus necessitates continuous monitoring and control.
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Ghosh S, Parthasarathi BC, Kumar B. Current status and future prospects of multi-antigen tick vaccine. J Vector Borne Dis 2021; 58:183-192. [DOI: 10.4103/0972-9062.321739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Kasozi KI, Welburn SC, Batiha GES, Marraiki N, Nalumenya DP, Namayanja M, Matama K, Zalwango KK, Matovu W, Zirintunda G, Ekou J, Kembabazi S, Mugasa CM, Kitibwa A, Tayebwa DS, Musinguzi SP, Mahero M, Ssengendo I, Nanteza A, Matovu E, MacLeod ET. Molecular epidemiology of anaplasmosis in small ruminants along a human-livestock-wildlife interface in Uganda. Heliyon 2020; 7:e05688. [PMID: 33437885 PMCID: PMC7788096 DOI: 10.1016/j.heliyon.2020.e05688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 09/28/2020] [Accepted: 12/04/2020] [Indexed: 12/14/2022] Open
Abstract
Background Information as regards the epidemiology of the Anaplasmataceae in small ruminants in several low- and middle-income countries is scarce. Methods In this study a total of 712 DNA samples collected from small ruminants were analyzed for Anaplasmataceae and Anaplasma ovis using the 16S rRNA and MSP4 genes respectively. Infection risk was assessed by location, sex and age of the animals and qGIS® was used to construct spatial maps. Results The prevalence of Anaplasmataceae spp was 89.1% (95% CI: 77.5–95.9) and 79.1% (95% CI: 75.9–82.1) in ovines and caprines respectively (RR = 1.1, 95% CI: 1.0–1.3); higher than those previously reported in other eastern African countries. The prevalence of A. ovis was 26.1% and 25.4% for both ovines and caprines respectively with ovines showing significantly higher levels of infection than caprines (P < 0.05). The risk of Anaplasma ovis infections was not affected by age (OR = 1.2, 95% CI: 0.9–1.7) or sex (OR = 1.1, 95% CI: 0.6–2.0). Small ruminants located at the forest edge (<0.3 km) showed higher A. ovis prevalence than those found inland with infections present in the midland regions associated with increased agricultural activity. Conclusion Anaplasma ovis remains a major challenge for small ruminant husbandry in Uganda and infections are under-reported. Policy efforts to prioritize management of Anaplasmataceae for small ruminant health would promote livestock productivity in vulnerable communities, improving livelihoods and ecosystem health.
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Affiliation(s)
- Keneth Iceland Kasozi
- Infection Medicine, Deanery of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, United Kingdom
- Department of Animal Production and Management, Faculty of Agriculture and Agricultural Sciences, Busitema University Arapai Campus, Box 203 Soroti, Uganda
- School of Medicine, Kabale University, Box 317 Kabale, Uganda
- Corresponding author.
| | - Susan Christina Welburn
- Infection Medicine, Deanery of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, United Kingdom
- Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, International Campus, 718 East Haizhou Road, Haining 314400, China
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, AlBeheira, Egypt
| | - Najat Marraiki
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - David Paul Nalumenya
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Monica Namayanja
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Kevin Matama
- Kampala International University Western Campus, Box 71 Bushenyi, Uganda
| | - Kelly Katenta Zalwango
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Wycliff Matovu
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Gerald Zirintunda
- Department of Animal Production and Management, Faculty of Agriculture and Agricultural Sciences, Busitema University Arapai Campus, Box 203 Soroti, Uganda
| | - Justine Ekou
- Department of Animal Production and Management, Faculty of Agriculture and Agricultural Sciences, Busitema University Arapai Campus, Box 203 Soroti, Uganda
| | | | - Claire Mack Mugasa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Annah Kitibwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Dickson Stuart Tayebwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Simon Peter Musinguzi
- Faculty of Agriculture and Environmental Sciences, Kabale University, Box 315 Kabale, Uganda
| | - Michael Mahero
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, USA
| | - Ibrahim Ssengendo
- Kampala International University Western Campus, Box 71 Bushenyi, Uganda
| | - Anne Nanteza
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Enock Matovu
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Box 7062 Kampala, Uganda
| | - Ewan Thomas MacLeod
- Infection Medicine, Deanery of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, United Kingdom
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Takata M, Misato S, Ozoe F, Ozoe Y. A point mutation in the β-adrenergic-like octopamine receptor: possible association with amitraz resistance. PEST MANAGEMENT SCIENCE 2020; 76:3720-3728. [PMID: 32431064 DOI: 10.1002/ps.5921] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/11/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Amitraz is a unique formamidine-class acaricide/insecticide that effectively controls ticks, mites, and insect pests. However, the recent emergence of amitraz-resistant cattle ticks is a serious problem that requires an urgent solution. A nonsynonymous single nucleotide polymorphism (A181T) leading to an amino acid substitution (I61F) in the β-adrenergic-like (β-AL) octopamine receptor (OAR) of amitraz-resistant southern cattle ticks (Rhipicephalus microplus) (RmβAOR) was proposed to be a cause of the amitraz resistance. However, it remains unclear whether this substitution exerts any functional effect on the action of amitraz. To make this clear, the functional role of this mutation was examined using an orthologous OAR (BmOAR2) from the silkworm (Bombyx mori). RESULTS Both amitraz and its metabolite N2 -(2,4-dimethylphenyl)-N1 -methyformamidine (DPMF) elevated intracellular cyclic AMP levels as orthosteric OAR agonists in HEK-293 cells stably expressing BmOAR2. The I45F mutant of BmOAR2 (equivalent to I61F in RmβAOR) was generated and tested for its sensitivity to amitraz and DPMF. The assay result showed that the I45F mutation reduces the potency of DPMF to a level similar to that of the endogenous agonist (R)-OA in wild-type BmOAR2. CONCLUSION The amino acid substitution found in the first transmembrane segment of RmβAOR most likely causes target-site insensitivity to DPMF, which might contribute to the resistance of R. microplus to amitraz. This needs to be further confirmed using RmβAOR. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Mizuki Takata
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Seishi Misato
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Fumiyo Ozoe
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Yoshihisa Ozoe
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
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Tumwebaze MA, Byamukama B, Tayebwa DS, Byaruhanga J, Angwe MK, Galon EM, Liu M, Lee SH, Ringo AE, Adjou Moumouni PF, Li J, Li Y, Ji S, Vudriko P, Xuan X. First Molecular Detection of Babesia ovis, Theileria spp., Anaplasma spp., and Ehrlichia ruminantium in Goats from Western Uganda. Pathogens 2020; 9:pathogens9110895. [PMID: 33121172 PMCID: PMC7692732 DOI: 10.3390/pathogens9110895] [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: 09/28/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 12/14/2022] Open
Abstract
Ticks and tick-borne diseases are major impediments to livestock production. To date, there have been several studies on the prevalence of tick-borne pathogens (TBPs) in cattle, but very few studies have documented TBPs in goats in Uganda. In this study, polymerase chain reaction assays and sequence analysis of different molecular markers were used to assess the presence and genetic characteristics of TBPs in 201 goats from Kasese district in western Uganda. The risk factors associated with TBP infections were also analyzed. We detected Theileria spp. (13.4%), Anaplasma phagocytophilum (10.9%), Anaplasma ovis (5.5%), Babesia ovis (5.5%), and Ehrlichia ruminantium (0.5%). The sequences of B. ovis ssu rRNA and A. ovismsp4 genes showed some degree of diversity among the parasite isolates in this study. The E. ruminantium pCS20 sequence formed a well-supported clade with isolates from Amblyomma variegatum ticks from Uganda. Wildlife interaction, sampling location, low body condition score, tick infestation, and herd size were significantly associated with TBP infections in the goats. The findings in this study provide important information on the epidemiology of tick-borne pathogens in Uganda, and show that goats could be potential reservoirs for tick-borne pathogens.
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Affiliation(s)
- Maria Agnes Tumwebaze
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
| | - Benedicto Byamukama
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
| | - Dickson Stuart Tayebwa
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
- Department of Veterinary Pharmacy, Clinical & Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda
| | - Joseph Byaruhanga
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
| | - Martin Kamilo Angwe
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
| | - Eloiza May Galon
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Mingming Liu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Seung-Hun Lee
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
- College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea
| | - Aaron Edmond Ringo
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
- Zanzibar Livestock Research Institute, Ministry of Agriculture, Natural Resources, Livestock and Fisheries, P.O. Box 159 Zanzibar, Tanzania
| | - Paul Franck Adjou Moumouni
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Jixu Li
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Yongchang Li
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Shengwei Ji
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
| | - Patrick Vudriko
- Research Center for Tropical Diseases and Vector Control, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda; (D.S.T.); (J.B.); (M.K.A.)
- Department of Veterinary Pharmacy, Clinical & Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala 7062, Uganda
- Correspondence: (P.V.); (X.X.)
| | - Xuenan Xuan
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; (M.A.T.); (B.B.); (E.M.G.); (M.L.); (S.-H.L.); (A.E.R.); (P.F.A.M.); (J.L.); (Y.L.); (S.J.)
- Correspondence: (P.V.); (X.X.)
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Ni J, Ren Q, Luo J, Chen Z, Xu X, Guo J, Tan Y, Liu W, Qu Z, Wu Z, Wang J, Li Y, Guan G, Luo J, Yin H, Liu G. Ultrasound-assisted extraction extracts from Stemona japonica (Blume) Miq. and Cnidium monnieri (L.) Cuss. could be used as potential Rhipicephalus sanguineus control agents. Exp Parasitol 2020; 217:107955. [PMID: 32649953 DOI: 10.1016/j.exppara.2020.107955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 05/18/2020] [Accepted: 07/03/2020] [Indexed: 12/01/2022]
Abstract
Nicotiana tabacum, Stemona japonica, and Cnidium monnieri are common plants that are widely used for their anti-parasitic properties. The purpose of this study was to evaluate the acaricidal activity of extracts from these plants against the brown dog tick, Rhipicephalus sanguineus. A composition analysis of crude extracts by GC-MS was conducted to discover compounds with acaricidal effects. The toxicity of extraction against the engorged nymphs of R. sanguineus was evaluated by an immersion test. The results showed that the crude extracts of S. japonica and C. monnieri in varying ratios, concentrations, and from different extraction methods, had a killing effect on R. sanguineus. Lethality reached 76.67% ± 0.04410 when using a 1:1 extract of S. japonica:C. monnieri in 75% ethanol with ultrasonic extraction; the crude extract was determined at a concentration of 0.5 g/mL. GC-MS results showed that osthole and 5-hydroxymethylfurfural (5-HMF) are the main components of the extract. These results suggested that ultrasound-assisted extraction (UAE) extracts contained acaricidal components acting against R. sanguineus, which may result in the development of effective extracts of S. japonica and C. monnieri as a source of low-toxicity, plant-based, natural acaricidal drugs.
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Affiliation(s)
- Jun Ni
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Qiaoyun Ren
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Jin Luo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Ze Chen
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Xiaofeng Xu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Junhui Guo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Yangchun Tan
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Wenge Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Zhiqiang Qu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Zegong Wu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Jinming Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Youquan Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Guiquan Guan
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Jianxun Luo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China
| | - Hong Yin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, 225009, PR China
| | - Guangyuan Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
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Nchu F, Nyangiwe N, Muhanguzi D, Nzalawahe J, Nagagi YP, Msalya G, Joseph NA, Kimaro EG, Mollel M, Temba V, Harouna DV. Development of a practical framework for sustainable surveillance and control of ticks and tick-borne diseases in Africa. Vet World 2020; 13:1910-1921. [PMID: 33132605 PMCID: PMC7566270 DOI: 10.14202/vetworld.2020.1910-1921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 07/22/2020] [Indexed: 12/24/2022] Open
Abstract
A workshop on ticks and tick-borne diseases (T&TBDs) was held on June 25 and 26, 2019, at the Tropical Pesticides Research Institute, Division of Livestock and Human Diseases Vector Control, Arusha, Tanzania. The objectives of the workshop were to discuss the current situation and to formulate actionable strategies to improve surveillance and control of T&TBDs in Africa. The workshop was funded by the National Research Foundation and the Cape Peninsula University of Technology and attended by livestock health providers, farmers, and researchers from East, West, and Southern African countries. During the workshop, experts presented recent surveillance data focused on T&TBDs; participants discussed research opportunities and community engagement. The primary outcome of the workshop was the creation of a new research consortium known as The African Consortium for T&TBDs. The consortium is intended to function as a community for researchers, students, farmers, policymakers, extension workers, and community members who are interested in the advancement of T&TBD control. The consortium will engage in research activities that focus on comprehensive surveillance of T&TBDs, developing tick acaricide resistance, alternative tick control programs, and policy development and education. These areas were identified as top priorities to be developed to improve T&TBD control on the continent.
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Affiliation(s)
- Felix Nchu
- Department of Horticultural Sciences, Cape Peninsula University of Technology, Bellville, Symphony Way, Bellville, Cape Town, 7535, South Africa
| | - Nkululeko Nyangiwe
- Department of Rural Development and Agrarian Reform, Döhne Agricultural Development Institute, Private Bag X15, Stutterheim 4930, South Africa.,Department of Conservation Ecology and Entomology, University of Stellenbosch, Stellenbosch 7602, South Africa
| | - Dennis Muhanguzi
- Department of Biomolecular and Biolaboratory Sciences, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Jahashi Nzalawahe
- Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P. O. Box 3019, Chuo Kikuu, Morogoro, Tanzania
| | - Yakob Petro Nagagi
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - George Msalya
- Department of Animal, Aquaculture and Range Sciences, College of Agriculture, Sokoine University of Agriculture, P. O. Box 3004, Chuo Kikuu, Morogoro, Tanzania.,Laboratory of Animal Breeding and Genetics, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
| | - Natala Audu Joseph
- Department of Veterinary Parasitology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Esther Gwae Kimaro
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Margaret Mollel
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Violet Temba
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Difo Voukang Harouna
- Department of Food Biotechnology and Nutritional Sciences, Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
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Byaruhanga J, Odua F, Ssebunya Y, Aketch O, Tayebwa DS, Rwego IB, Vudriko P. Comparison of Tick Control and Antibiotic Use Practices at Farm Level in Regions of High and Low Acaricide Resistance in Uganda. Vet Med Int 2020; 2020:4606059. [PMID: 32908661 PMCID: PMC7474386 DOI: 10.1155/2020/4606059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 03/19/2020] [Accepted: 07/01/2020] [Indexed: 11/25/2022] Open
Abstract
Uganda has experienced tick acaricide resistance in the livestock sector. With increase in incidence of tick-borne diseases (TBDs), use of antibiotics for control of TBDs and other opportunistic diseases has raisedserious concerns. The purpose of this study was to compare the farmers' tick control and antibiotic use practices on farms in regions of low (LARA) and high (HARA) tick acaricide resistance in Uganda, determine the prevalence of antibiotic residues in milk from both regions, and identify factors associated with antibiotic residues in milk. One representative district was selected from each region from which 10 farms were randomly selected. Delvotest SP-NT® test kit was used to detect antibiotic residues in milk. Half-body tick counts and acaricide efficacy tests were performed. Majority (70%) of HARA's respondents reported a corresponding increase in a monthly incidence of TBDs with an average of 3.2 cases of TBDs treated per farm compared to 0.2 cases in LARA. East Coast fever (ECF) was identified as the most common TBD in both regions, though cases of coinfection were more common in HARA. Half of HARA's respondents reported a corresponding increase in the use of antibiotics on their farms due to tick resistance compared to LARA. Antibiotics were the most used drugs on farms in both regions with oxytetracycline being the commonly used antibiotic. Ticks from HARA were resistant to deltamethrin, amitraz, and coformulation (chlorpyriphos and cypermethrin) while resistance against deltamethrin was confirmed in LARA. HARA farms had a significantly higher prevalence of antibiotic residues (21.25%) in raw milk than in LARA (4%) farms (p < 0.05). Acaricide resistance and practice of reading drug use instructions were significantly associated with antibiotic residues in milk at farm level. Overall, the study provides vital information linking acaricide resistance to antibiotic use practices, consequently leading to antibiotic residues in milk.
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Affiliation(s)
- Joseph Byaruhanga
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Fred Odua
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Yvette Ssebunya
- Division of Veterinary Regulation and Inspection, Department of Animal Health, Ministry of Agriculture, Animal Industry and Fisheries, Entebbe, Uganda
| | - Olivia Aketch
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Dickson Stuart Tayebwa
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Innocent B. Rwego
- One Health Division, Department of Veterinary Population Medicine, College of Veterinary Medicine, St. Paul, Falcon Heights, MN 55108, USA
- Department of Biosecurity, Ecosystems and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Patrick Vudriko
- Research Center for Tropical Diseases and Vector Control, Department of Veterinary Pharmacy, Clinics and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
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Resistance of ticks on cattle to amitraz in Zimbabwe. Trop Anim Health Prod 2020; 52:3323-3330. [PMID: 32780260 DOI: 10.1007/s11250-020-02364-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/31/2020] [Indexed: 10/23/2022]
Abstract
Resistance of one host and three host ticks on cattle to amitraz was studied using samples from five diptanks in the Domboshawa Communal Land Area of Zimbabwe. A random tick profile and a questionnaire survey on the tick control practices of the area were also carried out. Engorged Rhipicephalus (Boophilus) decoloratus, Rhipicephalus appendiculatus and Amblyomma hebraeum females were randomly collected from cattle presented for dipping at the 5 diptanks and were allowed to oviposit separately at T: 28 °C and RH: 85-95%. Larvae obtained were tested for resistance against various amitraz concentrations (1-0.0078125%) using the Larval Packet Test (LPT) and were compared with susceptible reference strains of R. (B.) decoloratus (Makuti strain, 2017), R. appendiculatus (Lake Chivero strain, 2015) and A. hebraeum (Lake Mutirikwi strain, 2017). The most abundant tick species were R. (B.) decoloratus (27.2%), Hyalomma rufipes (20.0%), H. truncatum (16.0%), R. appendiculatus (12.0%) and R. evertsi evertsi (11.9%). Amblyomma hebraeum (8.6%) and A. variegatum (1.8%) were the least common in the collection; this suggests that they were not well established in Domboshawa. Low amitraz resistance (RL = I) was detected only in R. (B.) decoloratus at 2 of the 5 diptanks. In the future, decentralised tick control due to inadequate and inconsistent supply of acaricides could introduce a number of factors which could contribute towards resistance development.
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50
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Lubembe DM, Odongo DO, Salih DA, Sibeko-Matjila KP. Microsatellite and minisatellite genotyping of Theileria parva population from southern Africa reveals possible discriminatory allele profiles with parasites from eastern Africa. Ticks Tick Borne Dis 2020; 11:101539. [PMID: 32993948 DOI: 10.1016/j.ttbdis.2020.101539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/20/2020] [Accepted: 07/30/2020] [Indexed: 10/23/2022]
Abstract
The control of Theileria parva, a protozoan parasite that threatens almost 50% of the cattle population in Africa, is still a challenge in many affected countries. Theileria parva field parasites from eastern Africa, and parasites comprising the current live T. parva vaccine widely deployed in the same region have been reported to be genotypically diverse. However, similar reports on T. parva parasites from southern Africa are limited, especially in Corridor disease designated areas. Establishing the extent of genetic exchange in T. parva populations is necessary for effective control of the parasite infection. Twelve polymorphic microsatellite and minisatellite loci were targeted for genotypic and population genetics analysis of T. parva parasites from South Africa, Mozambique, Kenya and Uganda using genomic DNA prepared from cattle and buffalo blood samples. The results revealed genotypic similarities among parasites from the two regions of Africa, with possible distinguishing allelic profiles on three loci (MS8, MS19 and MS33) for parasites associated with Corridor disease in South Africa, and East Coast fever in eastern Africa. Individual populations were in linkage equilibrium (VD<L), but when considered as one combined population, linkage disequilibrium (VD>L) was observed. Genetic divergence was observed to be more within (AMOVA = 74%) than between (AMOVA = 26%) populations. Principal coordinate analysis showed clustering that separated buffalo-derived from cattle-derived T. parva parasites, although parasites from cattle showed a close genetic relationship. The results also demonstrated geographic sub-structuring of T. parva parasites based on the disease syndromes caused in cattle in the two regions of Africa. These findings provide additional information on the genotypic diversity of T. parva parasites from South Africa, and reveal possible differences based on three loci (MS8, MS19 and MS33) and similarities between buffalo-derived T. parva parasites from southern and eastern Africa.
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Affiliation(s)
- Donald M Lubembe
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
| | - David O Odongo
- School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - Diaeldin A Salih
- Central Veterinary Research Laboratory, P.O. Box 8067, Khartoum, Sudan
| | - Kgomotso P Sibeko-Matjila
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa
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