Enterovirus infection in a semi-closed community.

Infection with enteroviruses was studied over a 61-week period (during 1960-61) in a semi-closed child community in the Detention Home of the Allegheny County Juvenile Court in Pittsburgh, Pennsylvania. While most of the viruses isolated were known adeno- and enterovirus types, three apparently represent new enterovirus types or 'prime strains'. Viruses were isolated in all but 6 weeks of the 61-week study period from the gastro-intestinal tracts of 110 children out of a total population of 514 (21%); of these 110, 24 children (22%) excreted virus at the time of admission. The population averaged 37 children (more than half of whom were under 5 years of age), with a turnover of about nine per week. Spread of infection in this community on introduction of a new virus was demonstrated, with virus shedding of variable duration after infection. Thirteen of the 110 positive children (12%) showed mixed virus infections. During the entire study period, no clinical diarrheal illness was found associated with the viral infections detected.