A serologic survey of RS infection by complement fixation test was conducted on 305 cases of acute respiratory illness and 76 nonrespiratory control cases at our hospital in Tokyo from May, 1960 to May, 1961, and from April, 1962 to January, 1963. Twenty cases (6.5%) were serologically diagnosed as having RS infection in the respiratory disease group. Those are the first cases of RS infection to be reported in Japan. The majority of the cases were found from September to January. RS infection was more frequent among the ward patient (10.3%) than the out-patients (6.5%).
In two cases of 79 controls inapparent infection with RS virus were found.
Multiserologic responses to certain other respiratory viruses accompanied with antibody response to RS virus were experienced in 12 cases, in which simultaneous rise to adenovirus was most frequent. The age distribution of RS complement fixing antibody among healthy children in the Tokyo area was similar to these observed in U.S.A. and indicated that a high percentage of children aquired RS infection at preschool age, the antibody incidence as high as 58% at five year of age.
The clinical signs and symptoms of RS virus infection were nothing particular from other common viral infections of the respiratory tract. Young children seemed to be liable to show low respiratory tract involvement.
