By Jonny Lupsha, Freelance News Writer

Doctors are claiming that allergy season will last longer and be more severe this year, CBS Philadelphia reports. This is due to the extended pollen blooming season likely caused by climate change. How do allergies affect your body?

Seasonal allergies affect millions of Americans, ranging from minor cases of sniffles all the way up to and including death. As spring starts to spring earlier and the Earth stays warmer for longer periods of time, allergy cases are on the rise. While some reactions can be prevented or subdued with simple antihistamines, many people with allergies require regular shots or need to carry epi-pens with them. Reviewing and understanding the causes of allergic reactions can help us make sense of why our bodies go berserk around pollen, peanuts, and other things that don’t have an effect on other people.

Breaking Down Anaphylaxis—Literally

Anaphylaxis is the most severe form of all allergic reactions. “Symptoms can include respiratory problems, vomiting, diarrhea, hives, and loss of bladder control,” said Dr. Bruce E. Fleury, Professor of the Practice in the Department of Ecology and Evolutionary Biology at Tulane University. “Blood pressure drops so quickly that victims sometimes slip into shock and die.”

The cause of anaphylaxis initiates from the first contact with an allergen, also called a “sensitizing dose,” which causes the body to develop a major sensitivity to the allergen upon further contact. If the body comes into contact with that same allergen again, the immune system severely overreacts, termed as a “shocking dose.” “Between 1 percent to 5 percent of American citizens are at risk for anaphylaxis, and 1 percent of those who have a reaction will die from it—around 1,500 deaths per year,” Dr. Fleury said. “The incidence of anaphylaxis, like that of allergies, in general, is rapidly increasing; it has more than doubled since the 1980s.”

Researchers at Johns Hopkins are currently experimenting with lowering the allergen sensitivity of people with allergies. For example, researchers “gave increasingly large amounts of bee venom to their bee-sensitive subjects and reduced the chance of shock to 2% after three to five years of regular treatment,” Dr. Fleury said. “This kind of therapy is called desensitization.”

When Asthma Attacks

Hay fever, a relatively new but very common cause of allergies, is a reaction to plant antigens such as pollen. However, in Dr. Fleury’s words, “pollen grains are much too large to get through the tiny airways that lead into the lungs, so hay fever is an upper respiratory problem. Asthma, on the other hand, is a chronic allergic condition which primarily affects the lower respiratory system.”

Due to a high level of an immunoglobulin called IgE in the blood, asthmatics are hypersensitive to allergens. Stress and exercise can also trigger asthma, constricting the airways tightly and causing shortness of breath. In order to have their airways reopened, some asthmatics need to be hospitalized. Severe asthma attacks can be fatal.

But why do we have asthma? Some evidence supports the idea that the IgE system evolved as a sort of defense mechanism against parasitic worms, like hookworm. Research experiments with lab rats shows resistance to parasitic worms is affected directly by the rats’ IgE levels. “But in our modern sanitized environments, this adaptation is no longer necessary for survival, so the system now overreacts to common allergies,” Dr. Fleury said.

Whether stocking up on antihistamines or inhalers, sufferers of allergies should keep an eye on local pollen counts and be wary of a prolonged allergy season this year. If nothing else, it may help reduce the number of boxes of tissues you need to purchase.

Dr. Bruce E. Fleury, Ph.D., contributed to this article. Dr. Fleury is Professor of the Practice in the Department of Ecology and Evolutionary Biology at Tulane University. He earned a B.A. from the University of Rochester in Psychology and General Science, and an M.A. in Library, Media, and Information Studies from the University of South Florida.