The disease is blood borne and is usually transmitted by mosquitoes.
Mosquitoes become infected after feeding on the blood of carrier
birds and then transmit the disease to humans and other animals.
Less then 1% of mosquitoes are carriers, and less than 1%
percent of people who are bitten and become infected will become
severely ill. Fatality rates range from 3% to 15%. People and
animals with weak immune systems and those who are debilitated, as
well as the very young and very old, are at risk of developing
severe cases of the disease.
There are no vaccines approved for small animals. Owners should minimize their pets' exposure to mosquitoes by taking actions aimed at reducing the number of mosquitoes around the home and neighborhood (eliminating standing water, maintaining windows and screens) and at protecting the animals from mosquito bites (avoiding dusk and dawn exposure). There are a few mosquito repellents for pets that can be used safely, however, any other products may be toxic and must be avoided.[Back]