UV Effects on Environmental Microbiomes May Improve Pediatric Asthma Outcomes

UV filtration was associated with a decrease in the abundance of bacteria and organisms commonly associated with the oral microbiome

MILWAUKEE, Feb. 25, 2026 /PRNewswire/ -- UV filtration in heating, ventilation and air conditioning may affect environmental microbial diversity, leading to improvements in children's asthma outcomes, according to new research being presented at the 2026 AAAAI Annual Meeting.

"Ultraviolet light has known bactericidal effects, but can that affect asthma outcomes? We created a pilot study that highlights the potential of bacterial changes in the setting of HVAC-based ultraviolet light to affect asthma symptom modulation and control," says lead author Kaleb D. Ware, MD.

In this study, pediatric asthmatic patients were enrolled and randomized to receive either UV filtration (CREON2000A) or a "sham device" in their HVAC units. Dust samples were collected from household carpets of participants at the time of device placement and once again after 12 months. Changes in bacterial alpha/beta-diversity and species, relative to their abundance, were examined in 14 paired dust samples with sufficient quantity (UV filtration [n=7] or sham device [n=7] homes) and were correlated with the primary endpoint, the Composite Asthma Severity Index (CASI).

The researchers compared the UV filtration to the "sham" conditions, noting there was no discernable difference in alpha/beta-diversity or differential species abundance. However, for homes with the CREON2000A device, there was a logfold >2 decrease in the relative abundance of certain organisms commonly associated with the oral microbiome, per one-unit improvement in CASI from the baseline to follow-up (false discovery rate p-value <0.25). Improvement in the CASI was also associated with enrichment in several common gut commensals.

The researchers suggest that this data supports further investigation of UV filtration in homes and public institutions, including schools, as adjuvant treatment for asthma.

Visit aaaai.org to learn more about indoor allergens. Research presented at the 2026 AAAAI Annual Meeting, February 27 – March 2 in Philadelphia, PA, is published in an online supplement to The Journal of Allergy and Clinical Immunology (JACI).

The American Academy of Allergy, Asthma & Immunology (AAAAI) is the leading membership organization of more than 7,100 allergists, asthma specialists, clinical immunologists and other professionals with a special interest in the research and treatment of allergic and immunologic diseases. Established in 1943, the AAAAI is the go-to resource for patients living with allergies, asthma and immune deficiency disorders.

SOURCE American Academy of Allergy, Asthma & Immunology (AAAAI)