The Geography of Hay Fever

Hay fever among US children varied according to the states they lived in

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) Red, running noses and watery eyes are all too common for those living with hay fever allergies. But kids in some states may deal with hay fever more than others.

A recent study found that the commonness of hay fever allergies varied among children based on the states they lived in.

Common symptoms of hay fever allergy include runny nose, itching, sneezing and a congested, stuffy nose.

Kids living in the South and Southeast in the US tended to be more likely to have hay fever than kids elsewhere in the US.

However, allergists say that moving to another state will not necessarily make a difference for kids.

"Ask an allergist about your child's allergy treatment."

The study, led by M.Z. Braunstein of New Rochelle, NY, aimed to better understand how the climate and living in different states influenced children's allergies.

The researchers examined the survey results of 91,642 children, aged 17 and under, who participated in the 2007 National Survey of Children's Health.

This information was compared to weather information gathered from the 2006-2007 National Climate Data Center and Weather Service.

The specific weather and climate information gathered included average annual and seasonal temperature, relative humidity, ultraviolet index, ozone levels, precipitation and drought index.

The researchers found that 18.5 percent of US children and teens experienced hay fever during the year, but the percentage by different states varied considerably.

Children and teens living in states in the Southeastern and Southern parts of the US were more likely to have hay fever than children in other parts of the country.

Hay fever was least common among children and teens living in Vermont, Montana and Alaska.

In assessing how common hay fever was, the researchers adjusted their findings to account for differences among the children in age, sex, race/ethnicity and household income.

Children and teens had about 10 percent lower odds of having hay fever if they lived in areas with an average annual relative humidity that was in the middle of the US measurements (not in the parts of the country with the highest or lowest measurements).

Kids also had about 14 percent lower odds of hay fever if they lived in areas with the highest drought index.

Meanwhile, children and teens were a little more likely to have hay fever if they were living in states with UV levels and average temperatures below the top 25 percent across the US.

The researchers basically concluded that various climate-related and weather-related factors did appear to influence children's likelihood of having hay fever allergies.

"According to the study, wetter regions with average humidity were associated with a decreased number of children with hay fever," said allergist Michael Foggs, MD, in a prepared statement.

Dr. Foggs is the president-elect of the American College of Allergy, Asthma and Immunology. "The study also found areas of the south with warm temperatures and elevated UV indexes seem to harbor more hay fever sufferers," he said in the statement.

However, these findings do not mean that children's allergies can necessarily be addressed by having the family move to another place.

Allergist Stanley Fineman, MD, said the study shows how climate influences allergens that can trigger allergy symptoms, but they may be inescapable.

"An allergy sufferer may escape one allergy to ragweed for example, only to develop sensitivity to other allergens, such as grasses, in a new location," Dr. Fineman said in a prepared statement. "Allergens, such as pollen, can be found in virtually all regions, including Hawaii, Alaska and Maine, making avoidance nearly impossible."

John Oppenheimer, MD, a physician at Pulmonary and Allergy Associates in New Jersey who was not associated with the study, noted that about 10 to 30 percent of the worldwide population has allergic rhinitis, and the numbers are growing.

"It is thus no surprise that research is focusing on potential contributing factors," he said. "In this study, Dr. Braunstein and Dr. Silverberg examined the association between climactic factors and prevalence of hay fever."

He said it was interesting that the prevalence of hay fever was lower in locations with second and third quartile mean annual relative humidity.

"Although additional research is needed to confirm these results and further explore the climactic contribution to hay fever prevalence, this study represents a very exciting step forward in our understanding of climate’s impact on the prevalence of hay fever," Dr. Oppenheimer said.

This study was presented November 8 at the Annual Scientific Meeting of the American College of Allergy, Asthma and Immunology.

The study has not yet been published in a peer-reviewed journal and therefore should be interpreted cautiously. No information was available regarding funding or authors' possible conflicts of interest.

Review Date: 
November 8, 2013
Last Updated:
December 30, 2013