抄録
Virological and epidemiological investigation of acute undifferentiated febrile illnesses, which occurred among a group of infants and children in the nursery of Tokyo from October, 1965 to December, 1968, were carried out by virus isolation and serological survey.
Sixteen species of virus were isolated during this period. Among them, nine viruses, i. e. parainfluenza 1, 2, 3, 4A, adeno 1, 3, 5, echo 7 and coxsackie B1 were isolated from epidemic cases, four viruses, i. e. adeno 2, 6, coxsackie A9 and herpes simplex were from sporadic cases. The remaining three viruses, i. e. polio 2, 3 and vaccinia were considered as derived from the results of vaccinations. Epidemics of parainfluenza 2 and 3 viruses, and a complex epidemic of parainfluenza 2, echo 7 and RS viruses were observed in 1965, 1966 and 1967 respectively. RS virus infections were confirmed only by serological test. In 1968, two complex epidemics by coxsackie B1, parainfluenza 4A and adeno 5 viruses, and, parainfluenza 1 and adeno 1 viruses were proved.
Results of serological investigations indicated that parainfluenza 2, 3, 4A, RS and echo 7 viruses spread effectively in this community. Especially parainfluenza 3 virus seemed to be the most effective spreader. Since high level of antibody titer against parainfluenza 3 virus had been kept in this group, repeated infection with this virus to the children having lowered antibody titer can be assumed. Our speculation is that, in Tokyo area, spreading of parainfluenza virus of each type gives the children many chances to get infections by these viruses every year. As to adenoviruses and enteroviruses, one type of virus will be replaced by another type of virus soon after the prevalence in this community.
We could not find any specific differences in clinical informations among all the above virus infections. Most of cases showed mild upper respiratory syndroms.
