B virus, Herpesvirus simiae: historical perspective.

Between 1932 and 1972, 24 known infections of man by B virus caused 23 cases of encephalitis and 18 fatalities. The virus has been isolated from dermal lesions and neural ganglia from macaque monkeys. Serological evidence of infection is complicated by close antigenic relationships between B virus, Herpesvirus simplex, and SA8. Hyperimmune globulin produced from monkey, horse, and rabbit sera has not proved highly effective. Formalin-inactivated vaccine appears safe and antigenic in man but has not been licensed. Half of all human subjects have neutralizing B virus antibody related to their H. simplex titer. More stable animal populations and the improved use of protective apparel have reduced, but not eliminated, the risk of B virus to man.