Recently, an outbreak of infectious disease has killed a number of cats on Maui. The disease has been confirmed as a strain of feline distemper, also called panleukopenia (from Latin, meaning lack of white blood cells). This disease has not been a problem in Hawai'i for many years, thanks to vaccinations.
Feline distemper/panleukopenia is more properly called feline parvo disease, since it is not related to the canine distemper virus, but is caused by a parvovirus. It is generally accepted that canine parvo disease evolved in 1978 from a viral mutation of the feline "distemper" parvovirus going from cats to dogs.
Canine parvovirus causes a fairly common disease in puppies and young dogs, with many cases diagnosed annually on Maui in unvaccinated or under-vaccinated dogs.
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Dr. Diane Shephard, DVM
Some of the newly identified canine parvo strains will infect and cause disease in cats. It is possible that the outbreak on Maui of feline parvo disease is from a mutation of canine parvo that is now able to infect cats.
Vaccination schedules for both cats and dogs should include "core" vaccines covering parvoviruses. Feline core vaccines will protect against both feline and canine parvoviruses. Kittens (and puppies) should be vaccinated two to three times at monthly intervals, until the age of 4 months, with a booster vaccine administered to one-year-olds. Thereafter, core vaccinations should be discussed at the yearly veterinary visit, and done at least every three years.
The disease is spread by contact with infected cats or by bedding, food bowls or other inanimate objects. The virus attacks rapidly dividing cells, so the signs include weakness, diarrhea and vomiting, neurological signs and even sudden death. Laboratory work shows low white blood cells and a positive viral antigen test on feces. There are no antiviral medications that can act directly on the virus, so treatment is supportive only. This treatment can be both expensive and prolonged, with no guarantee of survival. As with so many medical conditions, it is better to prevent rather than have to treat, so vaccinations are key to keeping cats healthy.
Dr. Diane Shepherd returned to Maui in 1987 to practice veterinary medicine at the Maui Humane Society. In 1997, opened Shepherd Veterinary Clinic. She can be contacted at 874-9372.