IMPACT OF THE BACTERIAL NASOPHARYNGEAL MICROBIOTA ON THE SEVERITY OF
GENUS ENTEROVIRUS LOWER RESPIRATORY TRACT INFECTION IN CHILDREN: A
CASE-CONTROL STUDY
Abstract
Introduction Rhinoviruses (RV) and Enteroviruses (EV) are among
the main causative etiologies of Lower Respiratory Tract Infection
(LRTI) in children. The clinical spectrum of RV/EV infection is wide,
which could be explained by diverse environmental, pathogen-, and
host-related factors. Little is known about the nasopharyngeal
microbiota as a risk factor or disease modifier for RV/EV infection in
pediatric patients. This study describes distinct nasopharyngeal
microbiota profiles according to RV/EV LRTI status in children.
Methods Cross-sectional case-control study, conducted at
Hospital Sant de Déu (Barcelona, Spain) from 2017 to 2020. Three groups
of children <5 years were included: healthy controls without
viral detection (Group A), mild or asymptomatic controls with RV/EV
infection (Group B), and cases with severe RV/EV infection admitted to
the pediatric intensive care unit (PICU) (Group C). Nasopharyngeal
samples were collected from participants for viral DNA/RNA detection by
multiplex-PCR and bacterial microbiota characterization by 16S rRNA gene
sequencing. Results A total of 104 subjects were recruited
(A=17, B=34, C=53). Children’s nasopharyngeal microbiota composition
varied according to their RV/EV infection status. Richness and diversity
were decreased among children with severe infection. Nasopharyngeal
microbiota profiles enriched in genus Dolosigranulum were related
to respiratory health, while genus Haemophiluswas specifically
predominant in children with severe RV/EV LRTI. Children with mild or
asymptomatic RV/EV infection showed an intermediate profile.
Conclusions These results suggest a close relationship between
the nasopharyngeal microbiota and different clinical presentations of
RV/EV infection.