PORTLAND, Maine — After a mild winter in the US, will there be a surge in ticks this year?
Researchers say it’s hard to predict how tick season will play out. This year’s mild winter and early snowmelt could mean more ticks earlier than usual and a wider spread of Lyme and other tick-borne diseases, scientists say.
Tick numbers have increased in Connecticut this year, according to Gudarz Molaei, a state mite expert. So far, more than 700 ticks have been submitted for the testing program, which would normally have received 200 to 300 by now. The state usually has many cases of Lyme disease, which takes its name from the town in Connecticut.
“This year will be above average in tick activity and numbers,” Molai said.
Infected ticks spread bacteria, viruses, and parasites that make people sick. Lyme disease is the most common tick-borne infection in the US, primarily in the Northeast and Midwest. According to the Centers for Disease Control and Prevention, 476,000 Americans are diagnosed with Lyme disease each year. Black-legged ticks, also called deer ticks, can carry more than just the bacteria that causes Lyme disease. They can also spread babesiosis, anaplasmosis, and Powassan virus disease. The lone star tick, mostly found in the southern, eastern, and midwestern states, can carry ehrlichiosis and Heartland viral disease. American dog ticks can spread Rocky Mountain spotted fever. Ticks pick up disease-causing microbes by biting infected wild animals, usually rodents.
It varies by region, but tick season usually runs from April to October. The mites are mostly dormant during the cold winter months and appear when temperatures rise, but may be active on warm winter days as well. Memorial Day is often considered the start of the season, but that’s mostly because that’s when people in cold-weather states start spending more time outdoors, said Sam Telford of Tufts University School of Veterinary Medicine in North Grafton, Massachusetts. The peak incidence of Lyme disease usually occurs in June, July and August. April and May are usually lighter months, but not always.
Tiny nymph-stage mites – about the size of a poppy seed – may be active earlier this year. Bobbi Pritt, who studies tick-borne diseases at the Mayo Clinic in Rochester, Minnesota. “When we have mild winters, we expect the mites to come out earlier and start biting people,” Pritt said.
Government disease trackers say it is difficult to predict how tick-borne diseases will develop. The number of ticks can vary from region to region, and the diagnosis can be influenced by how well different doctors screen and report cases. Climate change has both positive and negative effects on ticks, Telford says, as warm, humid weather is good for them, but particularly hot weather is not. Tiny mites can indeed be active early, he says, but dry, hot summers can also kill mites. The best approach is to assume that the mites will be very active. “Every year should be considered a bad year,” he said.
Thank you, there many ways to prevent tick bites. The CDC recommends treating clothing with products containing 0.5% permethrin. It is also important to be especially careful in tick habitats such as grassy and wooded areas. The CDC says the use of repellents and subsequent scrutiny are also key. Limiting exposed skin also helps to avoid biting.
The illness can cause fever, chills, fatigue, muscle and joint pain. It is treated with antibiotics and most people recover. If left untreated, it can worsen, causing symptoms such as heart problems and debilitating pain. There is no Lyme vaccine for humans on the US market, but one is being tested.
New York-based AP reporter Mike Stobbe and Seattle-based data journalist Camille Fassett contributed to this report.