AN ENDEMIOLOGICAL STUDY OF ENTERIC VIRUS INFECTIONS : POLIOMYELITIS, COXSACKIE, AND ORPHAN (ECHO) VIRUSES ISOLATED FROM NORMAL CHILDREN IN TWO SOCIO-ECONOMIC GROUPS

An endemiological study of enteric viruses was conducted among 136 normal children, living in households in two socio-economic groups, over a 29 month period in Charleston, West Virginia. A repeatable seasonal incidence of enteric virus excretion was noted with over 90 per cent of isolations occurring in the months of June to October. Of 592 stools examined in District I, a lower socio-economic group, 8.3 per cent yielded virus as compared to 3.1 per cent of 966 stools examined in District IV, an upper middle class district with good environmental sanitation. Among the 77 viruses isolated in tissue cultures of monkey kidneys, 44 per cent were ECHO or orphan viruses, 37 per cent Coxsackie viruses, and 19 per cent poliomyelitis viruses. Among poliovirus carriers, and 15 family contacts, 10 individuals had simultaneous heterotypic and type-specific antibody responses. The heterotypic ones were usually present at low levels and were transient in nature. Family infection with certain orphan viruses was also evident from antibody development which occurred following isolation of virus in the sentinel child.