Elucidating the outpatient burden of lower respiratory tract infections due to RSV and other viruses in children under 2 years of age: Clinical presentation, medical treatment, and family impact (Germany, 11/2022-10/2024).

OBJECTIVES

Worldwide, data on the burden of pediatric, outpatient-treated lower respiratory tract infections (LRTI) are limited. We investigated their viral etiology, clinical characteristics and family impact in Würzburg/Germany.

METHODS

Children aged <2 years presenting with febrile LRTI at nine pediatric practices from 11/2022-10/2023 were recorded. In a subset, oropharyngeal swabs were tested with multiplex-PCR for 18 respiratory viruses; clinical data were physician-reported and parent-reported (14-days diary; 1/3/12-month follow-up).

RESULTS

Among 474 recorded children, diagnoses were obstructive bronchitis/bronchiolitis (93.2%), pneumonia (3.4%), and stenosing laryngotracheitis (6.5%). Oropharyngeal swabs were collected from 107/474 (22.6%); RSV (33.6%), rhinovirus (27.1%), and hMPV (15.0%) were most frequently detected. Pediatricians classified 49.5%/48.6%/1.9% (of 107) as mildly/moderately/severely ill; 72.0% received beta-sympathomimetics; 15.0% antibiotics. In 65 diary-documented children, illness lasted 18 days (median; IQR 14-34), 46.2%/3.1% required additional visits/hospitalization, and parents reported 2.5 workdays missed (median). After 1/3/12 months, recurrent LRTI occurred in 11.3%/18.8%/35.5% and wheezing in 14.1%/20.2%/32.2%, with wheezing at 3- or 12-month follow-up associated with recurrent LRTI (Odds Ratio 13 and 7, P < 0.01).

CONCLUSIONS

Outpatient-treated LRTI in infants were usually mild/moderate but resolved slowly, with substantial family impact. RSV, rhinovirus, and hMPV predominated. Wheezing was reported in one-third after 12 months and was associated with recurrent LRTI. The present results provide a basis for assessing the impact of the recently recommended RSV immunization for all infants in Germany on the substantial burden of outpatient-treated LRTI in this particularly vulnerable age group.