CHARACTERIZATION AND DESCRIPTION OF A VIRUS CAUSING SALIVARY-GLAND HYPERPLASIA IN THE HOUSEFLY, MUSCA-DOMESTICA

A double-stranded DNA virus was isolated from hyperplasic salivary gla nds of male and female houseflies, Musca domestica L. (Diptera: Muscid ae), collected from a dairy in Alachua County, Florida, U.S.A. Sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE) of th is housefly salivary gland hyperplasia (SGH) virus revealed the presen ce of two major and eight minor structural polypeptides. Restriction e ndonuclease analysis indicated that the c. 137 kilobase pair DNA was d ouble-stranded. Weekly sweep-net sampling of the fly population throug hout the season (May-October, 1991) showed that 1.5-18.5% of the disse cted flies possessed hyperplasic salivary glands. The virus replicated within the nuclei of the salivary gland cells and was transmitted per os to newly-emerged healthy adult flies.