• Lyme disease awareness starts in May though ticks crawl sooner
  • Europe, Asia also face Lyme disease threat as infections rise

A wet and rainy start to May is no reason to forget that spring is here, and with it the ticks that cause Lyme disease and a host of other parasite-borne afflictions.

While a warm winter might have killed off some adult ticks, May is typically the month when the disease-ridden nymphs start to emerge and cases of Lyme begin ramping up. There is also evidence climate change is affecting the start of the season. Maine already started sounding the alarm in March. 

“One of the things we have found is that nymphs are coming out earlier when the climate warms,” said Richard Ostfeld, a disease ecologist at the Cary Institute of Ecosystem Studies in Millbrook, New York. “Over the last 20 years in southeastern New York, the nymph season has advanced by a couple of weeks and is projected to get even earlier.”

Lyme disease, the most well-known of the tick-borne illnesses, is prevalent in the U.S. Northeast and Midwest, as well as in parts of Canada, Europe and Asia. 

In 2014, 96 percent of confirmed Lyme disease cases in the U.S. were reported from 14 states: Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia and Wisconsin, according to the Centers for Disease Control and Prevention in Atlanta. About 76.5 million people live in those states, or 24 percent of the total U.S. population, according to U.S. Census Bureau estimates from 2015.

Although 30,000 cases of Lyme disease are reported to the CDC each year, the center cautions that this may not reflect the true scale of the problem. Some estimates put the number of people who get the disease each year at about 329,000.

Most Active

The illness can also be found in the U.K., France, Germany, Austria, Sweden and Russia. The Irish Health Service Executive reports 50 to 100 cases a year.

Lyme disease is at its worst in spring and summer months because that’s when most people go outside and nymphs, the second in the four-step blood-sucker life cycle, are most active.

“The main risk season is when the nymphs come out and they are quite tiny and really hard to see and feel,” Ostfeld said. “They tend to go undetected when they are crawling on your skin or embed in your skin sucking your blood.”

Adult ticks can spread disease just as easily as nymphs, though you’re more likely to feel them crawling up your back or across your face than their smaller relatives, according to Ostfeld.

Higher Metabolism

The fact this past winter was relatively mild in many places where they hunt, might actually be good for humans and bad for the ticks, said Maria Diuk-Wasser, a professor of ecology, evolution and environmental biology at Columbia University in New York. Warmer winter temperatures mean “their metabolism is higher, even if they may not move, thus burning more energy,” she said.

Of course, that doesn’t mean that anyone should go for a wander in the woods without first taking precautions. Using DEET with a 20 to 30 percent concentration or treating clothing with 0.5 percent of permethrin is a good start. Anyone who has been outside should bathe or shower within two hours of returning home and clothes should go into the dryer for one hour at high heat, the CDC said.

According to the center, the ticks lie at the tips of grass or leaves, with their legs outstretched, waiting for a human or an animal to brush past. They carry disease pathogens which they spread through their saliva after they cut through your skin to feed.

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