Effect of administration of sodium aurothiomalate on the virulence of yellow fever viruses in adult mice

Administration of sodium aurothiomalate (SATM) to adult mice results in a reduction of their average survival time (AST) following intracerebral challenge with the wild-type strains, Asibi and French viscerotropic virus (FVV), of yellow fever (YF) virus. Most attenuated 17D YF vaccines, derived by passage of the wild-type Asibi strain in chick tissue, showed no reduction in AST following intracerebral challenge and administration of SATM. In contrast, challenge with the majority of live attenuated French neurotropic vaccines, derived by passage of FVV in mouse brain, still resulted in SATM reducing the AST of mice. SATM also changed some YF viruses from non-lethal to lethal following intraperitoneal challenge and negated the ability of a monoclonal antibody to elicit passive protection of mice challenged intracerebrally with YF virus.