A Deterministic Model to Quantify Risk and Guide Mitigation Strategies to Reduce Bluetongue Virus Transmission in California Dairy Cattle

Christie Mayo; Courtney Shelley; N James MacLachlan; Ian Gardner; David Hartley; Christopher Barker

doi:10.1371/journal.pone.0165806

A Deterministic Model to Quantify Risk and Guide Mitigation Strategies to Reduce Bluetongue Virus Transmission in California Dairy Cattle

PLoS One. 2016 Nov 3;11(11):e0165806. doi: 10.1371/journal.pone.0165806. eCollection 2016.

Authors

Christie Mayo¹, Courtney Shelley², N James MacLachlan², Ian Gardner³, David Hartley⁴, Christopher Barker²

Affiliations

¹ Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, United States of America.
² Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America.
³ Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Prince Edward Island, Canada.
⁴ James M. Anderson Center for Health Systems Excellence, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States of America.

Abstract

The global distribution of bluetongue virus (BTV) has been changing recently, perhaps as a result of climate change. To evaluate the risk of BTV infection and transmission in a BTV-endemic region of California, sentinel dairy cows were evaluated for BTV infection, and populations of Culicoides vectors were collected at different sites using carbon dioxide. A deterministic model was developed to quantify risk and guide future mitigation strategies to reduce BTV infection in California dairy cattle. The greatest risk of BTV transmission was predicted within the warm Central Valley of California that contains the highest density of dairy cattle in the United States. Temperature and parameters associated with Culicoides vectors (transmission probabilities, carrying capacity, and survivorship) had the greatest effect on BTV's basic reproduction number, R0. Based on these analyses, optimal control strategies for reducing BTV infection risk in dairy cattle will be highly reliant upon early efforts to reduce vector abundance during the months prior to peak transmission.

MeSH terms

Animals
Bluetongue virus / physiology*
California
Cattle
Cattle Diseases / transmission*
Cattle Diseases / virology*
Dairying*
Models, Theoretical*
Risk
Seasons

Grants and funding

These studies were supported by funds provided by the Agriculture and Food Research Initiative competitive grant 2012-67015-19527 from the U.S. Department of Agriculture-National Institute of Food and Agriculture, and the Center for Food Animal Health at University of California-Davis, the US Department of Agriculture under the Animal Health Act, 1977, Public Law 95-113. Additional support was received from the Research and Policy for Infectious Disease Dynamics (RAPIDD) program of the Science and Technology Directorate, Department of Homeland Security and Fogarty International Center, National Institutes of Health.