Primary care respiratory syncytial virus disease characteristics in infants and young children in Germany: data from the prospective pediatric airway pathogen incidence surveillance network, 2021-2023

OBJECTIVES: Respiratory syncytial virus (RSV) is a major cause of morbidity globally, with most cases managed in outpatient settings. However, data characterizing the disease burden of non-severe RSV infections remain limited. METHODS: The prospective, multicenter pediatric airway pathogen incidence (PAPI) study enrolled 1450 children aged ≤24 months presenting with lower respiratory tract infections (LRTI) in outpatient settings between October 2021 and April 2023. Clinical data, detected pathogens via multiplex polymerase chain reaction, and follow-up data were collected. RESULTS: Among enrolled patients 19.7% tested positive for RSV. RSV-positive patients (RSV+) exhibited distinct clinical characteristics, including significantly higher proportions of wheezing, crackles, and tachypnoea than RSV-negative patients. Notably, we identified a previously unreported association between RSV infection and atopic conditions, with RSV+ patients demonstrating higher proportions of atopic eczema (odds ratio 1.65 [95% CI: 1.05-2.61]). 96.5% of all RSV+ patients received pharmacotherapy, predominantly beta-sympathomimetics, inhaled saline, and antipyretics. The mean recovery time was 12 days. CONCLUSION: In the outpatient setting, RSV infections during the first 2 years of life present with distinct clinical features and increased morbidity compared with other respiratory pathogens. The association with atopic conditions warrants further investigation. These findings characterize the considerable RSV burden in primary care before the implementation of immunization measures. TRIAL REGISTRATION: DRKS00026155.