The classroom microbiome and asthma morbidity in children attending 3 inner-city schools

To the Editor: School endotoxin exposure contributes to asthma morbidity.1 Recent shotgun metagenomics studies suggest that microbial identity, rather than microbial toxin levels alone, drives impacts of microbial exposure on chronic diseases.2 In this pilot randomized controlled trial of the effect of school environmental interventions on indoor air quality and asthma symptoms, we sought to address 3 questions. [...]is the school microbial environment independently associated with asthma symptoms? [...]is the school microbiome modifiable?