Investigation of equine influenza transmission in NSW: walk, wind or wing?

Paula J. Spokes; Andrew J. N. Marich; Jennie A. Musto; Kate A. Ward; Adam T. Craig; Jeremy M. McAnulty

doi:10.1071/NB08025

RESEARCH ARTICLE

Investigation of equine influenza transmission in NSW: walk, wind or wing?

Paula J. Spokes ^A ^C , Andrew J. N. Marich ^B , Jennie A. Musto ^B , Kate A. Ward ^A , Adam T. Craig ^A and Jeremy M. McAnulty ^B

+ Author Affiliations

- Author Affiliations

^A NSW Public Health Officer Training Program, NSW Department of Health

^B Communicable Diseases Branch, NSW Department of Health

^C Corresponding author. Email: paula.spokes@doh.health.nsw.gov.au

NSW Public Health Bulletin 20(10) 152-156 https://doi.org/10.1071/NB08025
Published: 9 November 2009

Abstract

Objectives: An outbreak of equine influenza occurred in New South Wales in 2007. In addition to the local spread of the disease between bordering properties, windborne spread over several kilometres had been postulated as a possible method of transmission in this outbreak. This study aimed to describe potential modes of transmission for a property infected with equine influenza where no apparent epidemiological links to other infected properties were reported. Methods: A semi-structured questionnaire was administered to owners of affected properties. The questionnaire collected detailed transmission-risk information, including personnel movements, equipment sharing, and horse and other animal movements. Results: Interviews with property owners from one geographic area suggested the potential for birds and other animals – rather than wind – to facilitate transmission of equine influenza. Conclusion: This study described the potential for mechanical spread of equine influenza. Further research, including laboratory testing of bird plumage following contact with infected horses, may be useful to confirm the possibility of avian fomite transmission.

Acknowledgments

We would like to thank the equine influenza emergency management team from the NSW Department of Primary Industries including Bruce Christie, Steve Dunn and the veterinary epidemiologists for their support and advice during this study. We would also like to acknowledge the work of public health unit staff involved throughout the management of the equine influenza outbreak.

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