Studies on the epidemiology of child infections. 3. Parainfluenza viruses (types 1-4) and respiratory syncytial virus infections.
A seroepidemiological study on the rate of neutralizing antibodies for parainfluenza viruses (types 1-4) and for the respiratory syncytial virus in 2,514 infants and children between 0 and 15 years, residing in Bari and its hinterland was carried out. Positive results were very high for both the individual parainfluenza serotypes (81.7% for type 3, 78.0% for type 1, 76.6% for type 4, 71.9% for type 2) and for respiratory syncytial virus (88.5%). The pattern of infections due to respiratory syncytial virus differed from that of the parainfluenza viruses not only for the higher serologic positive rate, but also for the larger number of elevated titre responses in each age group.