By Chaffin Mitchell, AccuWeather staff writer
April 25,2017, 1:10:24PM,EDT
While many Southeastern cities top the list for worst cities for allergy sufferers, there are many factors, such as weather patterns and native plants, that go into deciding the worst allergy locations around the country.According to the Center for Disease Control, more than $18 billion is spent on nasal allergy health costs annually for more than 50 million Americans who suffer from symptoms.
The worst locations for allergies in the U.S. were ranked by the Allergy and Asthma Foundation of America during fall of 2016:
1. Jackson, Mississippi
2. Memphis, Tennessee
3. Syracuse, New York
4. Louisville, Kentucky
5. McAllen, Texas
The cities on the list were picked due to the length of allergy seasons. A longer warm season, with an earlier start to spring and a later end to warmth in fall, extends the growing season for allergen-producing plants in much of the Southeast.
"Cities such as those listed above are likely particularly bad due to a combination of what grows there based on climate and the weather," said Seth Hollander, chief medical officer for Greater Austin Allergy, Asthma and Immunology.
Pollen particles have to go airborne in high enough quantities to affect people.
"Airborne pollens are the pollens that cause the greatest problem for allergy sufferers. Plants that have airborne pollens rely on air currents to disperse the pollen," said David Shulan, a certified asthma and allergy consultant based in Albany, New York.
He said plants that have large flowers usually need to have insects carry the relatively heavy pollen because they tend to stay put and cause fewer allergies.
Low humidity, dry conditions and gentle breezes favor airborne pollen dispersal, experts agree.
It’s best to wait until the later morning or evening to go outside due to pollen levels. In the afternoon winds pick up, so wind-pollinated plants cause the most problems for allergy sufferers.
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Rain helps to lower pollen levels, but rain also helps the plants grow and produce more pollen. Not as many pollen-producing plants grow in drier places due to a lack of water and the presence of hot weather.
Shulan said weather can significantly affect pollen levels due to the effects on plant growth as well.
"In the northern part of the country, snow and damp conditions in the winter followed by a dry spring favors increased pollen production by trees," Shulan said.
However, a warm spell during budding season followed by very cold conditions can damage buds and reduce pollen production, according to Shulan.
Scientists and doctors have yet to find a way to entirely prevent allergies, but being proactive, avoiding allergens as much as possible and managing symptoms can help sufferers have a better quality of life.
Doctors recommend checking the Air Quality Index before leaving your home to see how polluted the air is in your area. Try to avoid places or situations that can cause an asthma attack or allergic reactions.
It is important to get tested so you know what you’re allergic to and what to avoid.