Boushey noted that the research team's new research associating increased bacterial diversity and abundance with lower risk appears to support the "hygiene hypothesis," which suggests that the increase in the prevalence of allergies and asthma in modern, westernized countries might be an unintended consequence of children being exposed to fewer bacteria in cleaner indoor environments.
"If confirmed by other studies, these findings might even have us think of returning to the patterns of exposure of the 1940's, when families were larger, food was less processed and sterilized, and children spent a lot of their time outdoors," he said.
In an editorial accompanying the study, Dennis R. Ownby, MD, professor of pediatrics at Georgia Regents University stated, "If it is true that cockroaches and mice are important sources of both major allergens and potentially allergy-suppressive bacteria, we have an interesting yin and yang which may explain some of the inconsistencies and apparent contradictions of previous reports regarding allergen exposures and urban asthma."
Lynch is leading a lab team that is examining microbes in stool from a different population, also being studied from birth, and she expects that the study will shed more light on gut microbes that might inhibit development of asthma and allergy.
|Contact: Jeffrey Norris|
University of California - San Francisco