Babies with higher amounts of the bacterium Lactobacillus in their nose or upper part of the throat during an acute respiratory syncytial virus (RSV) infection are less likely to develop childhood wheezing later on, a new suggests.
Lactobacillus is a type of “friendly” bacteria that normally live in the digestive, urinary, and genital systems without causing disease.
RSV is one of the most common causes of upper and lower acute respiratory infection in young children worldwide. Researchers say the new findings are important as they look to create interventions that prevent the development of childhood wheezing illnesses, including asthma.
Childhood wheezing illnesses have commonly been associated with RSV, however, the pathways underlying the association aren’t fully understood.
“These findings provide new insights not only about how RSV infection in infancy may cause wheezing later in life, but also how the normal bacteria that live in and on us may protect us from disease,” says Christian Rosas-Salazar, assistant professor of pediatrics at Vanderbilt University and a lead author of the study in the Journal of Allergy and Clinical Immunology.
The researchers conducted a study of previously healthy, term infants who had laboratory-confirmed RSV acute respiratory infection (ARI).
The infants were enrolled in the INSPIRE (Infant Susceptibility to Pulmonary Infections and Asthma Following RSV Exposure) study—a population-based birth cohort of infants born between June and December, designed for studying the first RSV infection during infancy. Eligible infants were enrolled from collaborating general pediatric practices throughout the Middle Tennessee region.
Researchers collected samples of bacteria from the infants’ noses and upper throats. The they followed the infants until age two, when they assessed their wheezing outcomes. The detection and increased abundance of Lactobacillus in the infants’ noses and throats was consistently higher in infants who did not develop wheezing at two years.
This information suggests “the detection of Lactobacillus in the nasopharynx of RSV-infected infants could be used as a biomarker for the later development of childhood wheezing illnesses,” the researchers say.
Additional researchers from Vanderbilt, Emory University, and the J. Craig Venter Institute are coauthors of the work.
The National Institutes of Health, the Vanderbilt Institute for Clinical and Translational Research, the Vanderbilt Faculty Research Scholars Program, and the Parker B. Francis Fellowship Program funded the work.
Source: Vanderbilt University