Mosquito-Borne Disease: Is Your Horse at Risk?

These pests can transmit a variety of dangerous pathogens, depending on certain factors in your region.
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Mosquito-Borne Disease: Is Your Horse at Risk?
Mosquitoes get infected with potentially fatal viruses by feeding on infected birds, after which they might turn to human or horse for another meal. | Photo: iStock

These pests can transmit a variety of dangerous pathogens, depending on certain factors in your region

We’re all too familiar with the irritating sound of a tiny buzzing mosquito planning an approach for landing and a bloodmeal. This arthropod is not only annoying but also dangerous; in fact, it could be one of the world’s most lethal creatures. The many potentially fatal viruses it can transmit to humans and animals include encephalitis, West Nile virus (WNV), dengue, and now Zika, among others. It can also pass along the deadly parasites that cause malaria, yellow fever, heartworm disease, and elephantiasis.

For such a small insect, it packs a big punch of torment and suffering worldwide, with more than 1 million people dying each year from mosquito-borne diseases.

Horses are not immune to the equine pathogens mosquitoes carry. Unless immunized against specific mosquito-borne viruses, known as arboviruses, a horse is at risk of contracting Eastern, Western, and Venezuelan equine encephalomyelitis (EEE, WEE, and VEE) viruses and West Nile virus, which can cause fatal neurologic disease. As these names suggest, certain encephalitides are more prevalent in particular regions, whereas WNV is endemic, or found regularly, throughout the continental United States

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Written by:

Nancy S. Loving, DVM, owns Loving Equine Clinic in Boulder, Colorado, and has a special interest in managing the care of sport horses. Her book, All Horse Systems Go, is a comprehensive veterinary care and conditioning resource in full color that covers all facets of horse care. She has also authored the books Go the Distance as a resource for endurance horse owners, Conformation and Performance, and First Aid for Horse and Rider in addition to many veterinary articles for both horse owner and professional audiences.

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