"Before this study, if you would have asked 10 allergy specialists if allergy prevalence varied depending on where people live, all 10 of them would have said yes, because allergen exposures tend to be more common in certain regions of the United States," Dr. Darryl Zeldin, scientific director of the National Institute of Environmental Health Sciences, part of the National Institute of Health, said in a statement.
"This study suggests that people prone to developing allergies are going to develop an allergy to whatever is in their environment. It's what people become allergic to that differs."
Zeldin and colleagues analyzed blood serum data compiled from approximately 10,000 Americans in the National Health and Nutrition Examination Survey 2005-06.
The study analyzed serum for nine antibodies in children ages 1-5, and nineteen antibodies in study subjects age 6 and older.
However, the researchers discovered one group did exhibit a regional response to allergens -- children ages 1 to 5, and children from the southern United States displayed a higher prevalence of allergies than their peers living in other U.S. regions.
The southern states included Texas, Oklahoma, Louisiana, Arkansas, Tennessee, Kentucky, Mississippi, Alabama, Georgia, West Virginia, Virginia, the Carolinas and Florida.
"The higher allergy prevalence among the youngest children in southern states seemed to be attributable to dust mites and cockroaches," said lead author Paivi Salo, an epidemiologist in Zeldin's research group."As children get older, both indoor and outdoor allergies become more common, and the difference in the overall prevalence of allergies fades away."
Socioeconomic status did not predict allergies, but people in higher socioeconomic status groups were more commonly allergic to dogs and cats while those in lower socioeconomic status groups were more commonly allergic to shrimp and cockroaches.
The study was published in the Journal of Allergy and Clinical Immunology.