Protection of Mice Against Vaccinia Virus by Administration of Benzaldehyde Thiosemicarbazone.

Abstract

Benzaldehyde thiosemicarbazone prevents multiplication of vaccinia virus in chick embryonic tissues when present in a concn. of 1 [mu]g./ml. of medium. Substitutions in the para position of the benzene nucleus or in the 4-position of the thiosemicarbazone portion of the molecule reduce virostatic activity. When fed in the diet, benzaldehyde thiosemicarbazone produces a marked degree of protection of mice inoculated intracerebrally with vaccinia virus. Derivatives with substitutions in the para position of the benzene nucleus or in the 4-position of the thiosemicarbazone portion of the molecule produce little or no protection against vaccinia infection in mice. The thiosemicarbazones do not appear to inactivate vaccina virus as the result of prolonged contact in vitro.