Fall Allergy Capitals Oct. 27, 2010 -- Dayton, Ohio, tops the Asthma and Allergy Foundation of America’s list as the toughest place to live in the fall for people with allergies, moving up from sixth in last year’s ranking of the nation’s 100 largest metropolitan areas.

The AAFA says the rankings are based on a scientific analysis of three factors: airborne pollen counts from grass, trees, weeds, and mold spores; the number of allergy medications used per patient; and the number of allergy specialists per capita in each area.

Dayton’s score was 100. The city that’s best for people with fall allergies, Portland, Ore., had a score of 34.49.

The top five allergy capitals for fall 2010 and their scores are:

Dayton, Ohio 100.00

Wichita, Kan. 97.58

Louisville, Ky. 96.61

Knoxville, Tenn. 95.63

Jackson, Miss. 95.01

The five cities with lowest scores, meaning the cities that are best for people with fall allergies, are:

Portland, Ore. 34.49

Seattle, Wash. 41.35

San Diego, Calif. 43.31

Sacramento, Calif. 45.26

Albany, N.Y. 48.24

The AAFA says 40 million Americans have allergic rhinitis, also called hay fever, seasonal allergies, or nasal allergies. Although many people with allergies stay indoors in the spring and fall, when pollen counts are high, the AAFA says the air inside homes can be more polluted than outdoor air. Besides pollen, other culprits that can trigger allergy symptoms include dust mites, animal dander, and cockroaches.

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