Aetiology and outcome of children hospitalised for acute respiratory tract infections in Europe: findings from a multi-country combined case-control and cohort study

26 Apr, 2020

Authors: M. Kohns Vasconcelos; on behalf of the PED-MERMAIDS Study Group

Published in: 30th European Congress on Clinical Microbiology and Infectious Diseases (ECCMID), April 2020

Background: Recently, major aetiology and outcome studies on paediatric acute respiratory tract infections (ARI) have been reported from LMICs. In contrast, studies using standardised protocols across Europe are lacking.

Materials/methods: The EU-funded Paediatric Multi-centre EuRopean study of MAjor Infectious Disease Syndromes (PED-MER- MAIDS) enrolled children under 5 years hospitalised for ARI and well controls across 11 EU countries. Information on symptoms, course of disease and clinical management was collected prospectively. Admission day nasopharyngeal swabs were analysed for influenza, parainfluenza, rhinovirus, coronavirus, metapneumovirus, bocavirus, respiratory syncytial virus (RSV), parechovirus, enterovirus and adenovirus and Streptococcus pneumoniae (Sp), Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydia pneumoniae and Staphyloccous aureus.

Results: 353 ARI children, median age 1.13 years (IQR:0.44-2.56) and 352 controls, median age 1.76 years (IQR:0.96-3.73) were enrolled over 21⁄2 years. Swabs were analysed from 327 ARI children and 302 controls. No potential pathogen was detect- ed in 4.6% of ARI, only bacteria in 10.9%, only viruses in 33.9% and both bacterial and viral potential pathogens in 51.4%. Codetection of multiple (up to 4) viruses occurred in 31.2% of ARI and codetection of multiple bacteria in 16.9%. The most commonly detected pathogens are listed in table 1. Respiratory pathogens were detected in 62.8% of controls. Of the frequently detected pathogens, only RSV and influenza were strongly associated with hospitalisation for ARI (table 1). The population attributable fractions (PAF) were 33.6% for RSV and 18.0% for Sp. 209 ARI children (60.6%) received antibiotics, but this was not associated with detection of bacterial pathogens in study samples (OR=0.78, 95%-CI:0.48-1.28). Length of stay in hospital ranged between 0 and 49 days (median 3, IQR:2-5) and no child in the study died after admission for ARI.

Conclusions: Similarly to LMIC studies, RSV had the highest PAF for ARI hospitalisation in Europe, but with considerably lower mortality.