Occurrence and frequency of coronavirus infections in humans as determined by enzyme-linked immunosorbent assay.

The occurrence of human coronavirus (HCV) infections was analyzed by using sequential sera taken between 1976 and 1981 from adults working in the London area. Antibody rises to HCV 229E and HCV OC43 group viruses were measured in serum samples from these subjects by enzyme-linked immunosorbent assay. HCV infections were found throughout the year, although most occurred during two periods, from June through September and from December through February. There were no marked seasonal differences in either the range of antibody rises obtained or in the HCV groups to which these antibody rises were directed. However, there were more HCV antibody rises during the summer than in the winter. The antibody duration varied considerably, but had a mean of 3.5 months. Finally, the frequency of HCV infection per person was calculated to be 1 per 7.8 months.