Although other animals, such as cattle, swine, and dogs, can become infected, they generally do not show signs of the disease or contribute to its spread. The majority of cases only develop mild flu-like symptoms. However, more serious disease causing fever, headache, muscle pain, prostration, vomiting, convulsions, and other neurologic symptoms can occur. Death occurs in 40-80percent of those who develop severe disease. All age groups were equally affected.
Diagnosis is based on tests of blood or spinal fluid, or isolation from the pharynx.
Anyone can get venezuela equine encephalitis. All ages are equally affected. There have been no cases in Canada or the USA since the early 1970's. However, there have been epidemics in Mexico in 1993 and 1996. Equine vaccination with the live attenuated TC-83 vaccine provides rapid immunity and, when combined with restriction of equine movements and quarantine, may limit the spread of epizootics and prevent their emergence.