Farm-level risk factors of increased abortion and mortality in domestic ruminants during the 2010 Rift Valley fever outbreak in central South Africa

Rostal, M. K., Cleaveland, S. , Cordel, C., Staden, L. v., Matthews, L. , Anyamba, A., Karesh, W. B., Paweska, J. T., Haydon, D. T. and Ross, N. (2020) Farm-level risk factors of increased abortion and mortality in domestic ruminants during the 2010 Rift Valley fever outbreak in central South Africa. Pathogens, 9(11), 914. (doi: 10.3390/pathogens9110914) (PMID:33158214) (PMCID:PMC7694248)

Abstract

(1) Background: Rift Valley fever (RVF) outbreaks in domestic ruminants have severe socio-economic impacts. Climate-based continental predictions providing early warnings to regions at risk for RVF outbreaks are not of a high enough resolution for ruminant owners to assess their individual risk. (2) Methods: We analyzed risk factors for RVF occurrence and severity at the farm level using the number of domestic ruminant deaths and abortions reported by farmers in central South Africa during the 2010 RVF outbreaks using a Bayesian multinomial hurdle framework. (3) Results: We found strong support that the proportion of days with precipitation, the number of water sources, and the proportion of goats in the herd were positively associated with increased severity of RVF (the numbers of deaths and abortions). We did not find an association between any risk factors and whether RVF was reported on farms. (4) Conclusions: At the farm level we identified risk factors of RVF severity; however, there was little support for risk factors of RVF occurrence. The identification of farm-level risk factors for Rift Valley fever virus (RVFV) occurrence would support and potentially improve current prediction methods and would provide animal owners with critical information needed in order to assess their herd’s risk of RVFV infection.

• Item Type: Articles
• Additional Information: This research was funded by U.S. Department of Defense, Defense Threat Reduction Agency, grant number HDTRA1-14-1-0029. The project depicted is sponsored by the U.S. Department of Defense, Defense Threat Reduction Agency
• Keywords: Rift Valley fever, abortions, deaths, Bayesian, clinical signs, risk factors, prediction, farm level, ruminants, hurdle multinomial.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Haydon, Professor Daniel and Cleaveland, Professor Sarah and Matthews, Professor Louise

Creator Roles

Cleaveland, S.: Conceptualization, Writing – original draft, Writing – review and editing, Supervision
Matthews, L.: Writing – original draft, Writing – review and editing, Supervision
Haydon, D. T.: Conceptualization, Methodology, Formal analysis, Writing – original draft, Writing – review and editing, Supervision

• Authors: Rostal, M. K., Cleaveland, S., Cordel, C., Staden, L. v., Matthews, L., Anyamba, A., Karesh, W. B., Paweska, J. T., Haydon, D. T., and Ross, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Pathogens
• Publisher: MDPI
• ISSN: 2076-0817
• ISSN (Online): 2076-0817
• Published Online: 04 November 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Pathogens 9(11): 914
• Publisher Policy: Reproduced under a Creative Commons License