title: Interactions of Respiratory Viruses and the Nasal Microbiota during the First Year of Life in Healthy Infants.
abstract: Traditional culture techniques have shown that increased bacterial colonization is associated with viral colonization; however, the influence of viral colonization on the whole microbiota composition is less clear. We thus aimed to understand the interaction of viral infections and the nasal microbiota in early life to appraise their roles in disease development. Thirty-two healthy, unselected infants were included in this prospective longitudinal cohort study within the first year of life. Biweekly nasal swabs (n= 559) were taken, and the microbiota was analyzed by 16S rRNA pyrosequencing, and 10 different viruses and 2 atypical bacteria were characterized by real-time PCR (combination of seven duplex samples). In contrast to asymptomatic human rhinovirus (HRV) colonization, symptomatic HRV infections were associated with lower alpha diversity (Shannon diversity index [SDI]), higher bacterial density (PCR concentration), and a difference in beta diversities (Jaccard and Bray-Curtis index) of the microbiota. In addition, infants with more frequent HRV infections had a lower SDI at the end of the study period. Overall, changes in the microbiota associated with symptomatic HRV infections were characterized by a loss of microbial diversity. The interaction between HRV infections and the nasal microbiota in early life might be of importance for later disease development and indicate a potential approach for future interventions.IMPORTANCERespiratory viral infections are very frequent in infancy and of importance in acute and chronic disease development. Infections with human rhinovirus (HRV) are, e.g., associated with the later development of asthma. We found that only symptomatic HRV infections were associated with acute changes in the nasal microbiota, mainly characterized by a loss of microbial diversity. Infants with more frequent symptomatic HRV infections had a lower bacterial diversity at the end of the first year of life. Whether the interaction between viruses and the microbiota is one pathway contributing to asthma development will be assessed in the follow-ups of these children. Independent of that, measurements of microbial diversity might represent a potential marker for risk of later lung disease or monitoring of early life interventions.
authors.affiliation: Division of Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland; University of Basel, Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Insa
authors.initials: I
authors.lastname: Korten
authors.affiliation: Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland; Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
authors.forename: Moana
authors.initials: M
authors.lastname: Mika
authors.affiliation: Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
authors.forename: Shkipe
authors.initials: S
authors.lastname: Klenja
authors.affiliation: Division of Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kieninger
authors.affiliation: Division of Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; University of Basel, Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Ines
authors.initials: I
authors.lastname: Mack
authors.affiliation: Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Barbani
authors.affiliation: Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
authors.forename: Meri
authors.initials: M
authors.lastname: Gorgievski
authors.affiliation: University of Basel, Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Urs
authors.initials: U
authors.lastname: Frey
authors.affiliation: Institute for Infectious Diseases, University of Bern, Bern, Switzerland; Department of Infectious Diseases, University Hospital Bern, Bern, Switzerland.
authors.forename: Markus
authors.identifier: 0000-0002-2418-6474
authors.initials: M
authors.lastname: Hilty
authors.affiliation: Division of Respiratory Medicine, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; University of Basel, Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Philipp
authors.initials: P
authors.lastname: Latzin
keywords: bacteriology; human rhinovirus; microbiota; pediatric infectious disease; respiratory viruses