Snowshoe Hare Virus

Abstract

This chapter provides an overview of the classification, description, hosts, key developments, and diagnostic techniques for the snowshoe hare virus. The virus belongs to the Bunyaviridae family and is a part of the Bunyavirus genus. The virus is a member of the California group of viruses. It causes an illness, usually in young children, characterized by fever, severe headache, and nausea. Man and small mammals, principally snowshoe hares and Arctic ground squirrels, are susceptible to the virus. Areas outside the Western Hemisphere are free from the virus. The snowshoe hare virus was originally isolated from the blood of a snowshoe hare collected in Montana in 1958. Winter maintenance of the virus may occur by transovarial transmission in a mosquito to its eggs, persistence in the overwintering adult mosquitoes, and/or by a chronic infection of the vertebrate reservoir. The snowshoe hare appears to be the principal vertebrate host, but in its absence, the role is fulfilled by a ground squirrel. Inoculation of tissue culture with confirmation by fluorescent antibody technique is the preferred method for the viral diagnosis. In some instances, the more expensive but sensitive method of intercerebral suckling mouse inoculation may be required to obtain an isolate.