Climate change may be linked to allergies

MADISON, N.J., May 24 (UPI) -- Increased prevalence of two allergens -- mold and ragweed -- linked to climate change may account for an increase in U.S. allergies, researchers suggest.

The Quest Diagnostics Health Trends Report -- Allergies Across America by Quest Diagnostics -- analyzed the results of ImmunoCAP specific Immunoglobulin E (IgE) blood testing to 11 common allergens, including common ragweed and mold, two house dust mites, cats and dogs, and five foods.

Dr. Stanley J. Naides, medical director of immunology at Quest Diagnostics, says high IgE sensitization level for a specific allergen is highly suggestive of an allergy, although physicians also evaluate symptoms, medical history and other factors in order to clinically diagnose an allergy.

"We believe this is the first large national study to show that the growing prevalence of allergies, suggested by other studies, is largely due to increases in environment-based allergens previously associated with climate change," Naides says in a statement. "Given concerns about a warming climate, additional research is needed to confirm these findings and assess the possible implications for public health."

During a four-year period, sensitization to common ragweed grew 15 percent nationally while mold grew 12 percent vs. sensitization to the other allergens combined increased 5.8 percent, Naides says.

A study published in March in the Proceedings of the National Academy of Sciences determined ragweed season was nearly a month longer in 2009 than in 1995 in northern parts of North America, possibly as a result of climate change. Mold, affected by precipitation, may also increase in prevalence with a warmer climate, Naides adds.