[The search for a viral etiology of myocarditis].

The results are presented of serological tests by the neutralization method for antigens of Coxsackie B group, and by the haemagglutination inhibition method for three types of parainfluenza and sporadic influenza virus in 529 patients with myocarditis. In 7 cases the virus was isolated from stools. Virus aetiology of the disease was confirmed in 23.4% of cases, on average. Raised levels of antibodies to Coxsackie B antigens were found more frequently than the levels of antibodies to parainfluenza viruses. Seroconversion was more frequent in infections by parainfluenza type 3 than type 2. During an influenza epidemic in 5 cases raised levels of antibodies to the epidemic-causing strain were observed.