Mack Virus--Serum and Gamma Globulin Neutralization of Unidentified Agent Isolated From Suspected Nonparalytic Poliomyelitis.

Abstract

Stools of a child believed to have nonparalytic poliomyelitis in Cincinnati,in 1947 were previously reported as containing poliomyelitis virus of unusually low virulence. The conclusion was based on histologic evidence in monkeys. Re-investigation with current in vitro methods reveals a cytopathogenic virus which is not related to poliomyelitis virus immunologically; is neutralized by patient''s convalescent serum but not by acute serum; and is neutralized by gamma globulin. Illness is not produced in monkeys or small animals. The agent may be the cause of human illnesses not yet defined.