The monopoly of minor group rhinovirus in respiratory virus infection in children during the SARS-CoV-2 pandemic

ABSTRACT

Rhinovirus (RV) is one of the pathogens causing acute and chronic respiratory illnesses worldwide in paediatric patients. Compulsory mask-wearing and high stringency of social distancing were executed in Hong Kong since the SARSCoV-2 outbreak. While other common respiratory viruses vanished in routine surveillance programme, two sudden upsurges of RV associated upper respiratory tract infections were observed from Oct. to Nov. 2020 after schools reopening, and Apr. to Aug. 2021. We aimed to investigate if these RVs have a prominent role in transmission by analysing the RV genotype composition, assessing their replication competence, and the clinical features of paediatric patients. RV specimens collected from the hospitalised patients were genotyped, with clinical features of the patient documented and compared to those obtained in the pre-COVID-19 period. The replication competence of the RVs was examined in the well-differentiated human nasopharyngeal epithelial cells (HNPEC), and the stability of the RVs on different materials was tested. We identified the monopoly of minor group RV in each of the study duration, namely RV-A47 (80%) and RV-A49 (51%), respectively. In contrast to a diversified RV genotype composition in 2018-19. Without prior in vitro adaptation, the two minor-group RVs replicated in the HNPECs effectively to a comparable level as in the laboratory strain RVA16. The rise of minor-group RVs and dominance of single RV genotype under strict social distancing and hand hygiene is remarkable. Further investigation of the viral determinant, with an assessment of transmissibility in an animal model, will be needed to validate the specific role of these RVs.