Seroprevalence of African horse sickness in selected donkey populations in Namibia.
Abstract: African horse sickness (AHS) is a non-contagious viral disease of horses and other equids caused by an arbovirus belonging to the Reoviridae family and genus Orbivirus. AHS is an endemic disease that is responsible for the death of a high number of horses every year in Namibia. At present, there is no information on the prevalence and distribution of AHS virus (AHSV) serotypes in the different regions of Namibia. Therefore, this survey aimed to fill this knowledge gap by investigating the AHSV seroprevalence in Namibian donkeys. Methods: A total of 260 blood samples (20 samples for each region) were randomly collected from donkeys aged between 3 and 5 years. Sera were screened for AHSV-specific immunoglobulin G antibodies using acommercial competitive enzyme-linked immunosorbent assay kit and samples positive to AHSV antibodies were further tested by serum neutralization (SN) assay to evaluate the AHSV serotype-specific immune response. Results: Seroprevalence of antibodies against AHSV in Namibian donkeys was 63.5%. The AHSV prevalence was significantly higher in the northern region (64%) than in the southern region (36%). A significantly (p<0.05) higher number of donkeys had antibodies against AHSV-6 (37.8%) and AHSV-9 (37.8%). The AHSV-2, AHSV-6, and AHSV-9 prevalence were higher (p<0.05) in the northern regions compared to the southern regions. None of the donkeys in this study, however, tested positive for AHSV-8. Conclusions: Results of the current study indicate that all AHSV serotypes have either circulated previously or are circulating in Namibia except for AHSV-8. In particular, AHSV-1, -2, -3, -4, -5, -6, and -9 serotypes have circulated or are circulating in the northern region of Namibia, while AHSV-1, -4, -5, -6, -7, and -9 have infected donkeys in the south. AHSV-9 and AHSV-6 were the most prevalent serotypes detected in donkeys in this study. SN results showed that several donkeys from Kavango East, Kavango West, and Ohangwena regions had been exposed to multiple serotypes, indicating the possibility of cocirculation of several strains in Namibia.
Copyright: © Molini, et al.
Publication Date: 2020-05-31 PubMed ID: 32636601PubMed Central: PMC7311865DOI: 10.14202/vetworld.2020.1005-1009Google Scholar: Lookup
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- Journal Article
Summary
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This study investigates the prevalence and distribution of African horse sickness virus (AHSV) serotypes in donkey populations across different regions in Namibia. Findings show that various serotypes of the virus have circulated in different regions, with AHSV-9 and AHSV-6 being the most prevalent.
Methodology
- The researchers collected 260 blood samples from donkeys aged between 3 and 5 years from various regions of Namibia.
- These samples were screened for AHSV-specific immunoglobulin G antibodies using a commercial enzyme-linked immunosorbent assay kit.
- Samples positive for AHSV antibodies were then evaluated via a serum neutralization assay to determine the specific AHSV serotype causing the immune response.
Results
- The seroprevalence of antibodies against AHSV in Namibian donkeys was found to be 63.5%.
- Analyzed by region, the prevalence of AHSV was significantly higher in the northern region (64%) compared to the southern region (36%).
- A larger number of donkeys had antibodies against serotypes AHSV-6 (37.8%) and AHSV-9 (37.8%), with these serotypes more common in the northern regions.
- No donkeys tested positive for AHSV-8 in this study.
Conclusions
- All serotypes of AHSV have been found to either currently or previously circulate in Namibia, except for AHSV-8.
- Specifically, serotypes AHSV-1, -2, -3, -4, -5, -6, and -9 have been found in the north, while AHSV-1, -4, -5, -6, -7, and -9 have been found in the south.
- The most prevalent serotypes detected in donkeys during this study were AHSV-9 and AHSV-6.
- Results from the serum neutralization assay suggested exposure to multiple serotypes in donkeys from the Kavango East, Kavango West, and Ohangwena regions, indicating possible co-circulation of various strains in Namibia.
Cite This Article
APA
Molini U, Zaccaria G, Kandiwa E, Mushonga B, Khaiseb S, Ntahonshikira C, Chiwome B, Baines I, Madzingira O, Savini G, D'Alterio N.
(2020).
Seroprevalence of African horse sickness in selected donkey populations in Namibia.
Vet World, 13(5), 1005-1009.
https://doi.org/10.14202/vetworld.2020.1005-1009 Publication
Researcher Affiliations
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale" 64100 Teramo Italy.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Department of Virology, Central Veterinary Laboratory, 24 Goethe Street, Windhoek, Namibia.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia, Neudamm Campus, Namibia.
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale" 64100 Teramo Italy.
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale" 64100 Teramo Italy.
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