Antibodies to Coronavirus OC 43 strain in the population of North-Eastern Hungary.

Monthly 120 serum samples were collected from healthy and clinically ill residents of North-Eastern Hungary in the years 1980 and 1981. Haemagglutination-inhibiting antibody to the strain Coronavirus OC 43 was detected in 58% of the 2881 samples. The rate of positive sera was the lowest, 23%, between 7 and 11 months of age and reached the peak of 70% between 15 and 19 years. It did not rise further with age. Paired sera was tested from 405 patients suffering from various diseases. A titre rise was shown in 23 patients; 12 of these were suffering from acute respiratory disease, another 7 showed simultaneous exacerbation of bronchial asthma or spastic bronchitis.