Between mild winters and abnormal springs, seasonal allergies are getting worse around the globe, two new studies said.

In March, University of Maryland researchers published a study in PLOS One demonstrating how climate change disrupts the timing of spring and increases seasonal allergies across the U.S.

And another recent study, published in The Lancet Planetary Health, suggested that although temperature increases vary by latitude, significant increases in pollen loads and pollen season duration “appears to be global and independent of latitude.”

In Bowling Green, allergy seasons are trending similarly.

“They’re starting earlier, they’re more severe and they’re lasting longer,” said Dr. Patricia Mercer, an allergist-immunologist at Graves Gilbert Clinic in Bowling Green.

Allergies are the sixth-leading cause of chronic illness in the U.S. More than 50 million Americans deal with seasonal, food, insect sting and drug allergies each year, which translates to a cost of about $18 billion, according to the Centers for Disease Control and Prevention.

Each spring, flowering plants, trees, grasses and weeds reproduce by creating a fine powdery substance called pollen, an airborne allergen and the most common form of seasonal allergies, which annually affects about 20 million people, according to the CDC.

In addition to economic burden, “it’s significant because it can affect your productivity,” said Angel Waldron, director of communications at the Asthma and Allergy Foundation of America. “It can be really difficult to manage common day-to-day functions if you’re suffering with itchy, watery eyes, nasal congestion and a runny nose.”

Pollen allergy symptoms typically include coughing, sneezing, itchy eyes, a runny nose or a sore throat. Sometimes allergies will trigger asthma attacks and even anaphylaxis, which is when a person’s immune system tightens airways and blocks breathing after a sudden release of chemicals.

Symptoms are worsening with climate change. Higher temperatures extend pollen seasons, and higher carbon dioxide levels encourage both greater pollen production and a higher allergen concentration of pollen, which can increase allergy severity, according to The Lancet Planetary Health study.

There are factors that compound the symptoms of seasonal allergies, including urban heat islands, which are metropolitan areas that trap more heat than nearby rural areas, and air pollution.

“Air pollution is making allergies more common,” Mercer said, pointing to evidence of higher allergy rates reported along interstates and urban areas with heavy car traffic.

The Asthma and Allergy Foundation of America placed Louisville – which consistently ranks as having one of the worst urban heat island effects – as the sixth-most challenging city to live in with spring allergies in 2019, and Nashville was ranked 63rd. AAFA only ranks the top 100 biggest cities, so Bowling Green wasn’t listed.

“We started this ranking about 15 years ago. Each year, we’ve steadily seen pollen counts go up and the seasons extend,” Waldron said.

In Kentucky, tree pollen starts in March and intensifies through April and May. Grass pollen starts in April and extends through the fall, according to Mercer.

“We have long growing seasons in Kentucky. That’s why we’re the big winners,” Mercer said.

Pollen forecasters predict high pollen counts in Bowling Green for the next several days, according to pollen.com.

There are methods to reduce allergies. While it’s impossible to entirely avoid pollen, there are simple steps for people to cut down their exposure. Shut the windows at night, roll up the car windows during drives and change indoor air filters, according to Mercer.

It’s also useful to track pollen counts and visit a board-certified allergist. Allergists can guide patients to the appropriate medications and, if severe enough, initiate immunotherapy – the controlled exposure to a substance to build immunity – through shots or sublingual pills or drops.

But the best way is to take notes of when allergies start and stop to help identify the tree or plant that is causing a person’s allergies.

“The main way we can help is testing to see exactly what it is you’re allergic to,” Mercer said.