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de Glanville WA, Allan KJ, Nyarobi JM, Thomas KM, Lankester F, Kibona TJ, Claxton JR, Brennan B, Carter RW, Crump JA, Halliday JEB, Ladbury G, Mmbaga BT, Mramba F, Nyasebwa OM, Rubach MP, Rostal MK, Sanka P, Swai ES, Szemiel AM, Willett BJ, Cleaveland S. An outbreak of Rift Valley fever among peri-urban dairy cattle in northern Tanzania. Trans R Soc Trop Med Hyg 2022; 116:1082-1090. [PMID: 36040309 PMCID: PMC9623736 DOI: 10.1093/trstmh/trac076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 07/12/2022] [Accepted: 08/01/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Human and animal cases of Rift Valley fever (RVF) are typically only reported during large outbreaks. The occurrence of RVF cases that go undetected by national surveillance systems in the period between these outbreaks is considered likely. The last reported cases of RVF in Tanzania occurred during a large outbreak in 2007-2008. METHODS Samples collected between 2017 and 2019 from livestock suffering abortion across northern Tanzania were retrospectively tested for evidence of RVF virus infection using serology and reverse transcription quantitative polymerase chain reaction (RT-qPCR). RESULTS A total of 14 RVF-associated cattle abortions were identified among dairy cattle in a peri-urban area surrounding the town of Moshi. RVF cases occurred from May to August 2018 and were considered to represent an undetected, small-scale RVF outbreak. Milk samples from 3 of 14 cases (21%) were found to be RT-qPCR positive. Genotyping revealed circulation of RVF viruses from two distinct lineages. CONCLUSIONS RVF outbreaks can occur more often in endemic settings than would be expected on the basis of detection by national surveillance. The occurrence of RVF cases among peri-urban dairy cattle and evidence for viral shedding in milk, also highlights potentially emerging risks for RVF associated with increasing urban and peri-urban livestock populations.
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Affiliation(s)
- William A de Glanville
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.,University of Global Health Equity, Kigali 6955, Rwanda
| | - Kathryn J Allan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.,School of Veterinary Medicine, University of Glasgow, Glasgow G61 1QH, UK
| | - James M Nyarobi
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.,Nelson Mandela African Institution of Science and Technology, Arusha 255, Tanzania
| | - Kate M Thomas
- Centre for International Health, University of Otago, Dunedin 9054, New Zealand.,Kilimanjaro Clinical Research Institute, Moshi 2236, Tanzania
| | - Felix Lankester
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164, USA.,Global Animal Health Tanzania, Arusha 1642, Tanzania
| | - Tito J Kibona
- Nelson Mandela African Institution of Science and Technology, Arusha 255, Tanzania
| | - John R Claxton
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Benjamin Brennan
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, G61 1QH, UK
| | - Ryan W Carter
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - John A Crump
- Centre for International Health, University of Otago, Dunedin 9054, New Zealand.,Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, NC 27710, USA.,Duke Global Health Institute, Duke University, Durham, NC 27710, USA.,Kilimanjaro Christian Medical University College, Tumaini University, Moshi 3010, Tanzania
| | - Jo E B Halliday
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Georgia Ladbury
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Blandina T Mmbaga
- Kilimanjaro Clinical Research Institute, Moshi 2236, Tanzania.,Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, NC 27710, USA.,Kilimanjaro Christian Medical University College, Tumaini University, Moshi 3010, Tanzania
| | - Furaha Mramba
- Tanzania Veterinary Laboratory Agency, Dar es Salaam 9254, Tanzania
| | | | - Matthew P Rubach
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, NC 27710, USA.,Duke Global Health Institute, Duke University, Durham, NC 27710, USA.,Programme in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore
| | - Melinda K Rostal
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.,EcoHealth Alliance, New York, NY 10018, USA
| | - Paul Sanka
- Tanzania Veterinary Laboratory Agency, Dar es Salaam 9254, Tanzania
| | | | - Agnieszka M Szemiel
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, G61 1QH, UK
| | - Brian J Willett
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, G61 1QH, UK
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
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2
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de Glanville WA, Nyarobi JM, Kibona T, Halliday JEB, Thomas KM, Allan KJ, Johnson PCD, Davis A, Lankester F, Claxton JR, Rostal MK, Carter RW, de Jong RMF, Rubach MP, Crump JA, Mmbaga BT, Nyasebwa OM, Swai ES, Willett B, Cleaveland S. Inter-epidemic Rift Valley fever virus infection incidence and risks for zoonotic spillover in northern Tanzania. PLoS Negl Trop Dis 2022; 16:e0010871. [PMID: 36306281 PMCID: PMC9665400 DOI: 10.1371/journal.pntd.0010871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 11/15/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a mosquito-borne pathogen that has caused epidemics involving people and animals across Africa and the Arabian Peninsula. A number of studies have found evidence for the circulation of RVFV among livestock between these epidemics but the population-level incidence of infection during this inter-epidemic period (IEP) is rarely reported. General force of infection (FOI) models were applied to age-adjusted cross-sectional serological data to reconstruct the annual FOI and population-level incidence of RVFV infection among cattle, goats, and sheep in northern Tanzania from 2009 through 2015, a period without reported Rift Valley fever (RVF) cases in people or animals. To evaluate the potential for zoonotic RVFV spillover during this period, the relationship between village-level livestock RVFV FOI and human RVFV seropositivity was quantified using multi-level logistic regression. The predicted average annual incidence was 72 (95% Credible Interval [CrI] 63, 81) RVFV infections per 10,000 animals and 96 (95% CrI 81, 113), 79 (95% CrI 62, 98), and 39 (95% CrI 28, 52) per 10,000 cattle, sheep, and goats, respectively. There was variation in transmission intensity between study villages, with the highest estimated village-level FOI 2.49% (95% CrI 1.89, 3.23) and the lowest 0.12% (95% CrI 0.02, 0.43). The human RVFV seroprevalence was 8.2% (95% Confidence Interval 6.2, 10.9). Human seropositivity was strongly associated with the village-level FOI in livestock, with the odds of seropositivity in an individual person increasing by around 1.2 times (95% CrI 1.1, 1.3) for each additional annual RVFV seroconversion per 1,000 animals. A history of raw milk consumption was also positively associated with human seropositivity. RVFV has circulated at apparently low levels among livestock in northern Tanzania in the period since the last reported epidemic. Although our data do not allow us to confirm human RVFV infections during the IEP, a strong association between human seropositivity and the FOI in cattle, goats, and sheep supports the hypothesis that RVFV circulation among livestock during the IEP poses a risk for undetected zoonotic spillover in northern Tanzania. We provide further evidence for the likely role of raw milk consumption in RVFV transmission from animals to people.
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Affiliation(s)
- William A. de Glanville
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- University of Global Health Equity, Kigali, Rwanda
- * E-mail: (WAdG); (SC)
| | - James M. Nyarobi
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Tito Kibona
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Jo E. B. Halliday
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Kate M. Thomas
- Centre for International Health, University of Otago, Dunedin, New Zealand
- Kilimanjaro Clinical Research Institute, Moshi, United Republic of Tanzania
| | - Kathryn J. Allan
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Paul C. D. Johnson
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Alicia Davis
- School of Social and Political Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Felix Lankester
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington, United States of America
- Global Animal Health Tanzania, Arusha, Tanzania
| | - John R. Claxton
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Melinda K. Rostal
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- EcoHealth Alliance, New York, New York, United States of America
| | - Ryan W. Carter
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Rosanne M. F. de Jong
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Matthew P. Rubach
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina, United States of America
- Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
- Programme in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore
| | - John A. Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina, United States of America
- Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
- Kilimanjaro Christian Medical University College, Tumaini University, Moshi, Tanzania
| | - Blandina T. Mmbaga
- Kilimanjaro Clinical Research Institute, Moshi, United Republic of Tanzania
- Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
- Kilimanjaro Christian Medical University College, Tumaini University, Moshi, Tanzania
| | - Obed M. Nyasebwa
- Ministry of Livestock and Fisheries, Dodoma, United Republic of Tanzania
| | - Emanuel S. Swai
- Ministry of Livestock and Fisheries, Dodoma, United Republic of Tanzania
| | - Brian Willett
- MRC University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Sarah Cleaveland
- School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail: (WAdG); (SC)
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3
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Thomas KM, Kibona T, Claxton JR, de Glanville WA, Lankester F, Amani N, Buza JJ, Carter RW, Chapman GE, Crump JA, Dagleish MP, Halliday JEB, Hamilton CM, Innes EA, Katzer F, Livingstone M, Longbottom D, Millins C, Mmbaga BT, Mosha V, Nyarobi J, Nyasebwa OM, Russell GC, Sanka PN, Semango G, Wheelhouse N, Willett BJ, Cleaveland S, Allan KJ. Prospective cohort study reveals unexpected aetiologies of livestock abortion in northern Tanzania. Sci Rep 2022; 12:11669. [PMID: 35803982 PMCID: PMC9270399 DOI: 10.1038/s41598-022-15517-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 06/24/2022] [Indexed: 11/15/2022] Open
Abstract
Livestock abortion is an important cause of productivity losses worldwide and many infectious causes of abortion are zoonotic pathogens that impact on human health. Little is known about the relative importance of infectious causes of livestock abortion in Africa, including in subsistence farming communities that are critically dependent on livestock for food, income, and wellbeing. We conducted a prospective cohort study of livestock abortion, supported by cross-sectional serosurveillance, to determine aetiologies of livestock abortions in livestock in Tanzania. This approach generated several important findings including detection of a Rift Valley fever virus outbreak in cattle; high prevalence of C. burnetii infection in livestock; and the first report of Neospora caninum, Toxoplasma gondii, and pestiviruses associated with livestock abortion in Tanzania. Our approach provides a model for abortion surveillance in resource-limited settings. Our findings add substantially to current knowledge in sub-Saharan Africa, providing important evidence from which to prioritise disease interventions.
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Affiliation(s)
- Kate M Thomas
- Centre for International Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
- Kilimanjaro Clinical Research Institute, Good Samaritan Foundation, Moshi, United Republic of Tanzania.
- Ministry for Primary Industries, New Zealand Food Safety, Wellington, New Zealand.
| | - Tito Kibona
- Nelson Mandela African Institution of Science and Technology (NM-AIST), Tengeru, United Republic of Tanzania
| | - John R Claxton
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - William A de Glanville
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Felix Lankester
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
- Global Animal Health Tanzania, Arusha, United Republic of Tanzania
| | - Nelson Amani
- Kilimanjaro Clinical Research Institute, Good Samaritan Foundation, Moshi, United Republic of Tanzania
| | - Joram J Buza
- Nelson Mandela African Institution of Science and Technology (NM-AIST), Tengeru, United Republic of Tanzania
| | - Ryan W Carter
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Gail E Chapman
- School of Veterinary Medicine, University of Glasgow, Glasgow, UK
| | - John A Crump
- Centre for International Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Kilimanjaro Christian Medical University College, Moshi, United Republic of Tanzania
| | | | - Jo E B Halliday
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | | | | | | | | | | | - Caroline Millins
- School of Veterinary Medicine, University of Glasgow, Glasgow, UK
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Blandina T Mmbaga
- Kilimanjaro Clinical Research Institute, Good Samaritan Foundation, Moshi, United Republic of Tanzania
- Kilimanjaro Christian Medical University College, Moshi, United Republic of Tanzania
| | - Victor Mosha
- Kilimanjaro Clinical Research Institute, Good Samaritan Foundation, Moshi, United Republic of Tanzania
| | - James Nyarobi
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Obed M Nyasebwa
- Ministry of Livestock and Fisheries, Zonal Veterinary Centre-Arusha, Arusha, United Republic of Tanzania
| | | | - Paul N Sanka
- Tanzania Veterinary Laboratory Agency, Arusha, United Republic of Tanzania
| | - George Semango
- Nelson Mandela African Institution of Science and Technology (NM-AIST), Tengeru, United Republic of Tanzania
| | - Nick Wheelhouse
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, UK
| | - Brian J Willett
- Medical Research Council, University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Kathryn J Allan
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- School of Veterinary Medicine, University of Glasgow, Glasgow, UK
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4
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de Glanville WA, Davis A, Allan KJ, Buza J, Claxton JR, Crump JA, Halliday JEB, Johnson PCD, Kibona TJ, Mmbaga BT, Swai ES, Uzzell CB, Yoder J, Sharp J, Cleaveland S. Classification and characterisation of livestock production systems in northern Tanzania. PLoS One 2020; 15:e0229478. [PMID: 33378382 PMCID: PMC7773236 DOI: 10.1371/journal.pone.0229478] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 12/07/2020] [Indexed: 01/03/2023] Open
Abstract
Livestock keepers in sub-Saharan Africa face a range of pressures, including climate change, land loss, restrictive policies, and population increase. Widespread adaptation in response can lead to the emergence of new, non-traditional typologies of livestock production. We sought to characterise livestock production systems in two administrative regions in northern Tanzania, an area undergoing rapid social, economic, and environmental change. Questionnaire and spatial data were collected from 404 livestock-keeping households in 21 villages in Arusha and Manyara Regions in 2016. Multiple factor analysis and hierarchical cluster analysis were used to classify households into livestock production systems based on household-level characteristics. Adversity-based indicators of vulnerability, including reports of hunger, illness, and livestock, land and crop losses were compared between production systems. Three distinct clusters emerged through this process. The ethnic, environmental and livestock management characteristics of households in each cluster broadly mapped onto traditional definitions of 'pastoral', 'agro-pastoral' and 'smallholder' livestock production in the study area, suggesting that this quantitative classification system is complementary to more qualitative classification methods. Our approach allowed us to demonstrate a diversity in typologies of livestock production at small spatial scales, with almost half of study villages comprising more than one production system. We also found indicators of change within livestock production systems, most notably the adoption of crop agriculture in the majority of pastoral households. System-level heterogeneities in vulnerability were evident, with agro-pastoral households most likely to report hunger and pastoral households most likely to report illness in people and livestock, and livestock losses. We demonstrate that livestock production systems can provide context for assessing household vulnerability in northern Tanzania. Policy initiatives to improve household and community well-being should recognise the continuing diversity of traditional livestock production systems in northern Tanzania, including the diversity that can exist at small spatial scales.
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Affiliation(s)
- William A. de Glanville
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Alicia Davis
- School of Social and Political Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Kathryn J. Allan
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Joram Buza
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - John R. Claxton
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - John A. Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, NC, United States of America
- Duke Global Health Institute, Duke University, Durham, NC, United States of America
- Kilimanjaro Christian Medical University College, Tumaini University, Moshi, Tanzania
| | - Jo E. B. Halliday
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Paul C. D. Johnson
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Tito J. Kibona
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Blandina T. Mmbaga
- Duke Global Health Institute, Duke University, Durham, NC, United States of America
- Kilimanjaro Christian Medical University College, Tumaini University, Moshi, Tanzania
- Kilimanjaro Clinical Research Institute, Moshi, Tanzania
| | - Emmanuel S. Swai
- Department of Veterinary Services, Ministry of Livestock and Fisheries, Dhaka, Tanzania
| | - Christopher B. Uzzell
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jonathan Yoder
- School of Economic Sciences, Washington State University, Pullman, WA, United States of America
| | - Jo Sharp
- School of Geography and Sustainable Development, University of St Andrews, St Andrews, United Kingdom
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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5
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Semango G, Hamilton CM, Kreppel K, Katzer F, Kibona T, Lankester F, Allan KJ, Thomas KM, Claxton JR, Innes EA, Swai ES, Buza J, Cleaveland S, de Glanville WA. The Sero-epidemiology of Neospora caninum in Cattle in Northern Tanzania. Front Vet Sci 2019; 6:327. [PMID: 31681800 PMCID: PMC6798052 DOI: 10.3389/fvets.2019.00327] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/11/2019] [Indexed: 11/13/2022] Open
Abstract
Neospora caninum is a protozoan intracellular parasite of animals with a global distribution. Dogs act as definitive hosts, with infection in cattle leading to reproductive losses. Neosporosis can be a major source of income loss for livestock keepers, but its impacts in sub-Saharan Africa are mostly unknown. This study aimed to estimate the seroprevalence and identify risk factors for N. caninum infection in cattle in northern Tanzania, and to link herd-level exposure to reproductive losses. Serum samples from 3,015 cattle were collected from 380 households in 20 villages between February and December 2016. Questionnaire data were collected from 360 of these households. Household coordinates were used to extract satellite derived environmental data from open-access sources. Sera were tested for the presence of N. caninum antibodies using an indirect ELISA. Risk factors for individual-level seropositivity were identified with logistic regression using Bayesian model averaging (BMA). The relationship between herd-level seroprevalence and abortion rates was assessed using negative binomial regression. The seroprevalence of N. caninum exposure after adjustment for diagnostic test performance was 21.5% [95% Credibility Interval (CrI) 17.9-25.4]. The most important predictors of seropositivity selected by BMA were age greater than 18 months [Odds ratio (OR) = 2.17, 95% CrI 1.45-3.26], the local cattle population density (OR = 0.69, 95% CrI 0.41-1.00), household use of restricted grazing (OR = 0.72, 95% CrI 0.25-1.16), and an increasing percentage cover of shrub or forest land in the environment surrounding a household (OR = 1.37, 1.00-2.14). There was a positive relationship between herd-level N. caninum seroprevalence and the reported within-herd abortion rate (Incidence Rate Ratio = 1.03, 95% CrI 1.00-1.06). Our findings suggest N. caninum is likely to be an important cause of abortion in cattle in Tanzania. Management practices, such as restricted grazing, are likely to reduce the risk of infection and suggest contamination of communal grazing areas may be important for transmission. Evidence for a relationship between livestock seropositivity and shrub and forest habitats raises questions about a potential role for wildlife in the epidemiology of N. caninum in Tanzania.
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Affiliation(s)
- George Semango
- Nelson Mandela African Institution of Science and Technology, Tengeru, Tanzania
| | - Clare M. Hamilton
- Moredun Research Institute, Pentlands Science Park, Edinburgh, United Kingdom
| | - Katharina Kreppel
- Nelson Mandela African Institution of Science and Technology, Tengeru, Tanzania
| | - Frank Katzer
- Moredun Research Institute, Pentlands Science Park, Edinburgh, United Kingdom
| | - Tito Kibona
- Nelson Mandela African Institution of Science and Technology, Tengeru, Tanzania
| | - Felix Lankester
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, United States
| | - Kathryn J. Allan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Kate M. Thomas
- Centre for International Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Good Samaritan Foundation, Kilimanjaro Clinical Research Institute, Moshi, Tanzania
| | - John R. Claxton
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Elizabeth A. Innes
- Moredun Research Institute, Pentlands Science Park, Edinburgh, United Kingdom
| | | | - Joram Buza
- Nelson Mandela African Institution of Science and Technology, Tengeru, Tanzania
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - William A. de Glanville
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
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6
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Hughes EC, Kibona TK, de Glanville WA, Lankester F, Davis A, Carter RW, de Jong RMF, Nyasebwa OM, Claxton JR, Cleaveland S, Allan KJ. Taenia multiceps
coenurosis in Tanzania: a major and under-recognised livestock disease problem in pastoral communities. Vet Rec 2019; 184:191. [DOI: 10.1136/vr.105186] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/02/2018] [Accepted: 11/16/2018] [Indexed: 11/03/2022]
Affiliation(s)
- Ellen C Hughes
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
| | - Tito K Kibona
- Nelson Mandela African Institute of Science and Technology, Arusha; Arusha Tanzania
| | - William A de Glanville
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
| | - Felix Lankester
- Paul G. Allen School for Global Animal Health, Washington State University; Pullman Washington USA
| | - Alicia Davis
- Institute of Health and Wellbeing, College of Social Sciences, University of Glasgow; Glasgow UK
| | - Ryan W Carter
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
| | - Rosanne M F de Jong
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
| | - Obed M Nyasebwa
- Zonal Veterinary Centre, Ministry of Livestock and Fisheries; Arusha Tanzania
| | - John R Claxton
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
- Nelson Mandela African Institute of Science and Technology, Arusha; Arusha Tanzania
| | - Kathryn J Allan
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow; Glasgow UK
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7
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Abstract
Fasciola hepatica causes significant morbidity and mortality in dairy cattle in the Andean region of Cajamarca, Peru, where prevalence of infection of up to 78% has been reported. ELISA and Western blot analyses were used to characterise antibody responses in dairy cattle to adult F. hepatica to excretory-secretory (E/S), somatic (SO) and surface (SU) antigens. Three groups of dairy cattle - calves, heifers and adult cows - naturally exposed to F. hepatica in this region, were monitored every 2 months over a 2-year period. Calves, heifers and adult cows all had antibodies which recognised a 28kDa protein in the SO preparation, whereas only adult cows had antibodies that recognised a 28kDa protein in E/S products. All three groups of cattle responded to a 60-66kDa group of proteins in E/S and SU preparations and a 17kDa antigen in SO products was recognised by antibodies from cows and heifers but not calves. The total antibody response to E/S antigens measured by ELISA, increased over time in calves and remained constantly high over the 2-year period in all three groups of cattle. Slight fluctuations in the antibody response occurred in the group of heifers and cows coinciding with seasonal changes in the level of challenge.
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Affiliation(s)
- P L Ortiz
- Facultad de Ceincias Veterinarias, Universidad Nacional de Cajamarca, Ciudad Universitaria, Cajamarca, Peru
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8
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Duff JP, Maxwell AJ, Claxton JR. Chronic and fatal fascioliasis in llamas in the UK. Vet Rec 1999; 145:315-6. [PMID: 10515620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- J P Duff
- Veterinary Laboratories Agency Penrith, Merrythought, Penrith, Cumbria
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9
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Abstract
The experiment aimed to measure the effect of constant and variable temperatures on the growth of Lymnaea viatrix snails, on the development of a Peruvian isolate of Fasciola hepatica eggs and on the development of F. hepatica in the snails. This was carried out by cultivating infected and uninfected snails and fluke eggs in artificial, temperature controlled chambers. L. viatrix snails were found to develop at a rate dependent on environmental temperature, but developed at least as well under conditions of varying temperature as at the same mean constant temperature. F. hepatica eggs held at constant or varying temperatures, developed at a rate comparable to other reports. However, eggs developing at varying temperatures appeared to have reduced hatchability. Parasite development within the snails was slow, though within the limits calculated from the literature, and varying temperature did not appear to reduce development compared to constant temperatures.
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Affiliation(s)
- J R Claxton
- University of Liverpool, Department of Veterinary Clinical Science and Animal Husbandry, Leahurst, Neston, UK.
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10
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Claxton JR, Zambrano H, Ortiz P, Delgado E, Escurra E, Clarkson MJ. Strategic control of fasciolosis in the inter-Andean valley of Cajamarca, Peru. Vet Rec 1998; 143:42-5. [PMID: 9699251 DOI: 10.1136/vr.143.2.42] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Fasciolosis is recognised as a major problem in dairy cattle in Cajamarca, Peru. The infection has an annual cycle, with the major period of infection from January to March. A control programme, involving two doses of the fasciolicide triclabendazole aimed at reducing the passage of Fasciola hepatica eggs on to the pasture, together with the use of the molluscicide, niclosamide, was evaluated against traditional treatment programmes. The double treatment regimen did not significantly reduce the overall parasite burden, as measured by faecal egg counts, but did control the parasites to a level similar to that achieved by traditional programmes averaging 3-7 treatments per year. The cows' eosinophil counts and serum liver enzyme activities were significantly lower than in animals treated by the traditional programmes. The use of niclosamide in addition to the triclabendazole treatments gave no clear advantage, although there was a significant reduction in the number of intermediate host snails after the application of the molluscicide.
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Affiliation(s)
- J R Claxton
- University of Liverpool, Department of Veterinary Clinical Science and Animal Husbandry, Leahurst, Neston, South Wirral
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11
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Claxton JR, Zambrano H, Ortiz P, Amorós C, Delgado E, Escurra E, Clarkson MJ. The epidemiology of fasciolosis in the inter-Andean valley of Cajamarca, Peru. Parasitol Int 1997. [DOI: 10.1016/s1383-5769(97)00039-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Abstract
Standard haematological values have been calculated for female Holstein and Brown Swiss cattle kept at high altitudes in the Andean Sierra. Overall mean values were 5.9 x 10(12) l-1 for the red cell count, 0.321 l-1 for the packed cell volume, 9.6 gdl-1 for the haemoglobin concentration, 55.0 femtolitres for the mean corpuscular volume, 30.5 gdl-1 for the mean corpuscular haemoglobin concentration and 16.7 pg for mean corpuscular haemoglobin. Red cell indices tended to be higher in Holstein cattle than in Brown Swiss kept at the same altitude and were higher in cattle kept at higher altitudes. Mean white cell parameters were 9.7 x 10(9) l-1 for total white cells, 2.6 x 10(9) l-1 for neutrophils, 0.086 x 10(9) l-1 for bands, 6.3 x 10(9) l-1 for lymphocytes, 0.7 x 10(9) l-1 for eosinophils, 0.073 x 10(9) l-1 for monocytes and 0.001 x 10(9) l-1 for basophils.
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Affiliation(s)
- J R Claxton
- University of Liverpool, Department of Veterinary Clinical Science and Animal Husbandry, Neston, South Wirral, UK
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13
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Abstract
An experiment was conducted in The Gambia to compare trypanosomosis incidence between zebu and N'Dama cattle. It was considered important to compare the 2 breeds under identical management conditions and the animals were maintained together at 3 locations, traditionally managed and under a range of tsetse challenges. The results show that trypanosomosis incidence was significantly higher in zebu than in N'Dama. Titre of antibody against Trypanosoma vivax measured by an IFAT showed a significant difference between zebu and N'Dama. Variations in packed cell volume were greater in zebu than in N'Dama.
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14
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Abstract
The incidence of trypanosome infections, measured by a Berenil Index in experimental herds of 10 Zebu and 10 N'Dama cattle, was compared with tsetse challenge and with the prevalence of parasitaemia in local N'Dama at three villages in Gambia. Tsetse challenge was more strongly correlated with the incidence of parasitaemia in the Zebu than in the N'Dama. There was a strong correlation between prevalence and incidence of infection in the N'Dama. There was no correlation, however, between prevalence of infection in cattle and tsetse challenge unless the data were offset by 3-5 months. The Berenil Index in the Zebu increased at about twice the rate as in the N'Dama under corresponding levels of challenge. It is concluded that whereas incidence of infection in susceptible animals is best measured independently, it can, under stable conditions, be inferred from an assessment of tsetse challenge.
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Affiliation(s)
- J R Claxton
- International Trypanotolerance Centre, Banjul, Gambia
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15
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Abstract
The prevalence of trypanosome infections in warthogs (Phacochoerus aethiopicus) in The Gambia was found to be 11% of a sample of 62 animals. All isolates were identified as Trypanosoma simiae. Serological evidence indicated a higher level of exposure to T. simiae, but results were inconclusive for the presence of Trypanosoma congolense. The course of T. simiae infection in warthog piglets showed a rapidly rising parasitaemia, with a concomitant fall in packed cell volume, and resulted in a prolonged period of low-level parasitaemia. The same infections killed domestic piglets.
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Affiliation(s)
- J R Claxton
- International Trypanotolerance Centre, Banjul, Gambia
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