Farm-Exposed Children Benefit from Specific Bacteria Reducing Asthma and Allergies

An international research team analyzed data from more than 1,000 children raised in rural settings and compared them with samples from cow‑barn dust. Genetic sequencing identified nine groups of gram‑positive bacteria that are strongly linked to a lower risk of asthma, hay fever and atopic dermatitis. The two most influential species, **Romboutsia timonensis** and **Glutamicibacter arilaitensis**, together account for roughly two‑thirds of the protective “farm‑effect” on asthma and about half of the effect on other allergic conditions.

The study also detected bacterial metabolites—kynurenine, xanthine, alpha‑linolenic acid and stearidonic acid—in barn dust. When inhaled, these compounds interact with receptors in the airway epithelium, dampening immune over‑reactions that cause allergy symptoms. The findings, published in *NEJM Evidence*, suggest that mimicking these microbial signals could lead to new preventive or therapeutic approaches for allergic diseases.