To study the molecular epidemiology of respiratory syncytial virus (RSV) in a community, children with acute respiratory symptoms at a pediatric outpatient clinic in Niigata, Japan, were analyzed over three seasons from Respiratory syncytial virus (RSV) is a major cause of serious acute lower respiratory disease in infants and young children and is found mainly in the late fall, winter, and spring (2, 8, 13, 15). Bronchiolitis and pneumonia are observed most frequently during the first few months of life (2,8,17). Almost all children are infected with RSV by age 2 years, and half have experienced two infections (8,11,17).RSV strains have been classified into antigenic groups A and B (RSV-A and RSV-B, respectively) on the basis of the reactivities of the viruses with monoclonal antibodies directed against the attachment glycoprotein (G protein) (1,7,12,19) and also by genetic analyses (9,25,26). G protein is the most variable RSV protein (10,14,19), and its C-terminal region (the second hypervariable region) accounts for strain-specific epitopes (3,4,6,9,14,22,23). The molecular epidemiology and evolutionary patterns of G protein have provided important information about the clinical and epidemiological features of RSV: several different genotypes cocirculate, and the one that predominates in a community every year may change (5,21,22,28). However, the importance of strain diversity to the clinical and epidemiological features of RSV has yet to be elucidated in detail.Our objectives in the present study were to clarify the molecular epidemiology of RSV in a community over three seasons, determine the relationship between genotypes and circulation patterns, and assess clinical features and repeated infections.
MATERIALS AND METHODSStudy population and clinical samples. The study was conducted over three seasons from
