EQUINE | Equine Disease Quarterly
of rabies become manifest and therapy is almost
invariably futile. Without early treatment, rabies is
nearly 100 percent fatal. Rabies is a zoonotic (capable
of being transmitted from animals to humans) disease
that is distributed nearly worldwide. Attention to the
disease is primarily focused on preventive and control
strategies. Many countries are considered rabies-free
for the purposes of importing dogs into the United
States (https://www.cdc.gov/importation/ rabies-free-
countries.html).
Rabies can be prevented by pre-exposure vaccination
of humans and animals. A human diploid cell vaccine
and a purified chick embryo vaccine are available
for humans (the latter is mainly used outside of the
USA) for pre- and post-exposure to rabies, with rabies
immune globulin available only for post-exposure
treatment in exposed humans.
Pre-exposure vaccination involves administration
of three doses of vaccine given over a one month
period. In unvaccinated humans, post-exposure
treatment consists of the administration of five doses
of vaccine. Vaccines for multiple species of domestic
animals are available to licensed veterinarians.
Wildlife vaccines may be available from veterinarians,
but are typically used in targeted locations by the
Kentucky Department of Fish and Wildlife and the
United States Department of Agriculture.
unsatisfactory for testing. Of the 733 positive animals,
only 7.2 percent (53 animals) were from domestic
species (i.e. pets and farm animals), and the other
92.8 percent (680 animals) were wildlife. Twenty-five
of the positive domestic animals were horses (Table
2), which means that horses accounted for less than 1
percent of the total positive rabies cases in Kentucky
over the last 29 years. Rabies-positive horses were
primarily located in Central Kentucky (Figure 1). The
terrestrial reservoir for rabies in the state is the striped
skunk, and skunks positive for rabies virus have been
located in all counties where infected horses have
resided (Figure 2).
As a closing comment, a robust surveillance program
involving the UK Veterinary Diagnostic Lab, Breathitt
Veterinary Center, the Kentucky Cabinet for Health,
Kentucky Fish and Wildlife, and USDA is in place
to thoroughly monitor rabies in Kentucky. The vast
majority of animals testing positive for rabies are
wildlife, with little or no exposure to humans, pets
and domestic animals. More importantly for horse
enthusiasts within the state, the number of horses
testing positive for rabies is extremely low.
CONTACT: Jacqueline Smith, PhD, [email protected], (859) 257-7559,
University of Kentucky Veterinary Diagnostic Laboratory, Lexington,
KY
From January 1989 through December 2017, Kentucky
tested 32,387 animals for rabies virus. Of this total,
2.3 percent (733 animals) tested positive, 93.1
percent (30,145 animals) tested negative, and 4.6
percent (1509 animals) were unsatisfactory for testing
(i.e. the sample was untestable due to maceration,
degradation, or insufficient material). Of note:
Animals suspected of having rabies should not be
euthanized by traumatic insult (e.g. gunshot) to the
brain, because trauma frequently renders the sample
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• Equine Health Update •