Sindbis Virus

Alphaviruses are mosquito-borne causes of acute encephalitis. In humans, the important alphaviruses causing encephalitis are Eastern equine, Western equine, and Venezuelan equine encephalitis viruses, all found in the Americas. Alphaviruses found in other parts of the world (e. g. , Ross River, Sindbis, Chikungunya, and O’Nyong-nyong viruses) cause syndromes of rash and arthritis without encephalitis (1). However, these Old World viruses often cause encephalitis in experimental animals and serve as important models of acute alphavirus encephalitis (). Sindbis virus (SV), the type strain of the alphaviruses, causes an acute age-dependent encephalomyelitis and is the best studied murine model of alphavirus encephalitis.