Achoo! 12 worst cities for allergy sufferers (CBS News) More than 40 million Americans suffer from nasal allergies, according to the Asthma and Allergy Foundation of America (AAFA). The AAFA says your nose knows when spring is near, because that's when pollen counts are highest and symptoms begin for many Americans. "Springtime allergy triggers - primarily tree pollen - cause symptoms including itchy runny nose, nasal and sinus congestion, repeated sneezing, watery eyes, inflamed sinuses and, in severe cases, difficulty breathing due to all of these symptoms," the AAFA explained. Nasal allergy symptoms can be even more problematic if you also have asthma. But not every city in the U.S. is equal when it comes to allergy season, says the AAFA. For the organization's annual list of "Allergy Capitals," researchers studied data from 100 of the largest metro areas in the country to create an allergy score based on pollen counts, how much over-the-counter and prescription allergy medications residents used, and the number of allergy specialists available per patient. Is your state an allergy capital? Keep clicking to find out...