Long Term Sequelae of Mild RSV Infections in Healthy Children Aged 0-3 Years in the Primary Care Setting-A Prospective Two Year Follow Up Observational Study.

Children with an early severe respiratory syncytial virus (RSV) infection have an increased risk of wheezing later in life. This longitudinal study aimed to investigate whether children with a mild RSV infection taken care of in a primary health care setting had an increased incidence of wheezing in the 2 years following infection compared to children with other respiratory infections (RSV-negative). Nasal swabs of children with acute respiratory infections were examined for 23 pathogens by multiplex PCR. 216 RSV-positive and RSV-negative (N = 201) matched for age, gender and time of diagnosis were followed for 2 years using telemedical control to record the occurrence of wheezing, hospitalization and frequency of respiratory tract infections. RSV-positive patients showed a 48% lower risk (OR 0.520, p = 0.03) of developing wheezing in the 2-year observation period compared to the RSV-negative group; Rhinovirus-positive patients had a trendwise increased risk (OR 1.47, p = 0.0872). These data were also reflected in a reduced prescription rate of short acting beta agonists in the RSV group. In conclusion, mild RSV infections led to fewer wheezing episodes in RSV-positive compared to RSV-negative patients. Rhinovirus infections appear to increase wheezing. Our data are consistent with the idea that there could be a dose-effect relationship with RSV infections.