What is SV40?
Simian virus 40, or SV40, was discovered in 1960. It occurs naturally in some species of monkeys, though it does not typically cause symptoms or illness except in cases where the animal has chronic problems with its immune system (Shah and Nathanson, 1976). In those cases, the animals develop lesions associated with SV40 in their kidneys and brains (Newman et al., 1998).