Why pollen season is starting earlier and how it could affect allergies [Video]

As the U.S. welcomes spring, it also means the arrival of allergy season, which affects millions of people.

High pollen levels can lead to a variety of symptoms including sneezing, runny nose, itchy and watery eyes, hives and coughing — and Americans may have to deal with them for much longer than in past years.

Typical allergy seasons are getting longer and more intense in North America because of climate change, research shows.

One 2020 study found that between 1990 and 2018, North American pollen seasons became 20 days longer on average with pollen concentrations increasing up to 21% during the same period.

Plants have more time to bloom and sprout leaves, releasing allergy-inducing pollen when there are longer periods of freeze-free days. With no mitigation, these trends will persist, further impacting respiratory health in the coming decades.

Parts of the Midwest, including the Ohio River Valley, are currently experiencing the earliest spring …