It's a viral disease that has threatened humans and animals since antiquity, and it's still fatal almost without exception
in all mammals that develop clinical signs.
As a professional, you know the danger and the importance of keeping horses on a regular vaccination schedule, but are your
clients on board and keeping vaccinations current?
Photo: Getty Images
When some equine diseases, particularly eastern equine encephalitis, increased sharply this year, many veterinarians suspected
that the weak economy played a role, prompting horse owners either to neglect vaccination or to extend recommended intervals
between inoculations. That raises the possibility that some clients might also skip rabies vaccinations for economic reasons,
reasoning that exposure is somewhat less common in horses than in other domestic animals.
The American Association of Equine Practitioners, however, emphasizes the importance of the rabies vaccination by identifying
it as one of four core vaccinations for horses. Core vaccinations, as defined by the American Veterinary Medical Association,
are those that are required by law or those that protect animals from diseases that:
- are endemic to a region
- have potential public health significance
- are highly infectious
- pose a risk of severe disease.
In addition, core vaccines have clearly demonstrated efficacy and safety, exhibiting a high enough level of patient benefit
and low enough level of risk to justify their use in the majority of patients.
But educating clients on the matter requires more than just passing along scientific information. Motivation is the key, and
to motivate effectively, you need to present a clear, concise plan of action—and repeat it several times. To assist you on
that front, Intervet/Schering-Plough Animal Health sponsored a webinar on
http://thehorse.com/ titled "Equine rabies: what every horse owner should know." The webinar is geared toward veterinarians and horse owners alike
and draws on the expertise of Dr. Amanda House, DACVIM, a professor of equine health at the University of Florida. "In 2007,
the Centers for Disease Control and Prevention reported 7,258 rabies cases in animals and one human case in the United States,"
Dr. House says. While 93 percent of the cases were in wildlife species, the remaining 7 percent were in horses, livestock,
dogs, and cats.
Client education shows results
In 2006, 53 rabies cases were reported in horses, according to the CDC—an increase of 12.8 percent over 2005. In 2007, that
number decreased by about 20 percent to 42 cases. In 2008, the number dropped again, to 30 cases. Why?
"We believe this decline is likely attributed to increased public awareness and vaccination," says Dr. Cynthia Guitierrez,
equine technical services veterinarian for Intervet/Schering-Plough Animal Health. And increased public awareness indicates
that many veterinarians are doing a better job of educating clients.
In the webinar, Dr. House emphasizes that the total number of rabies cases reported is a fraction of the cases that actually
occur. CDC numbers are based on cases seen and tested, and infected wildlife usually die unnoticed and unreported. Rabies
exposure in horses most often occurs through the bite of an infected animal, usually a raccoon, skunk, bat, or fox. "Horses
are naturally curious and interested in wild animals that approach them," Dr. House explains. Therefore clients should be
advised to limit horses' exposure to wildlife as much as possible.
When an unvaccinated horse is bitten, clinical signs can take anywhere from two weeks to 12 weeks to develop. If the bite
occurs on or near the head or neck, signs develop sooner because the virus travels a shorter distance to the spinal cord and
brain. If the bite is on the rump, the virus replicates in muscles and takes longer to reach the central nervous system. Once
signs do appear, death usually occurs in three to seven days, Dr. House explains.