Tick nymphs mean high risk for Lyme disease

By Douglas Karlson/ dkarlson@cnc.com
Friday, May 20, 2005

This is not a good time of year to go for a walk in the woods. You might get attacked by an Ixodes scapularis nymph. That's a baby deer tick.

According to entomologist David Simser, this is nymph season, and it's a bad one. Nymphs cause more cases of Lyme disease than adult ticks, and are most active in June.

"It seems like they're very active and they're numerous," said Simser, who's a tick expert with the Upper Barnstable County Cooperative Extension. After an especially cold and snowy winter, ticks may get a late start in finding a host - like a mouse, a deer or a human, and so once spring arrives they're frantic.

"We are now entering the high risk stage," said Simser. "As many as 25 percent of all nymphs may carry the Lyme disease. They carry other diseases too."

A single tick can, in fact, carry three or more different pathogens. Several of those are not uncommon on Cape Cod, said Simser. The three most common tick-borne diseases are Borreliosis, which is Lyme disease; Anaplasmosis (sometimes referred to as HGE or Ehrlichiosis) which has symptoms similar to Lyme disease, and Babesiosis, which resembles malaria.

Unlike Lyme disease, which takes at least 24 hours to be transmitted by a tick, Anaplasmosis can be transmitted in just 5 hours.

Ticks also carry Tularemia, which is rare but has been found on Martha's Vineyard, and Rocky Mountain spotted fever, which Simser said is very rare.

Lyme disease, especially when compounded with other tick-borne diseases, can be difficult to diagnose (there are up to 50 possible symptoms). Sometimes you have symptoms but the pathogen remains undetected.

"You're being told you're fine but you know you can't get out of bed," said Simser.

"The luckiest thing that can happen to a person who is bitten by an infected tick is to get that bull's-eye rash, because that's a definitive symptom," said Brenda Boleyn, chairwoman of the Cape & Islands Lyme Disease Task Force.

But not everyone gets the rash.

"It is a diabolical illness because it strikes people in so many different ways," said Boleyn. "People have to be increasingly vigilant."

"We are in an endemic area, and if we go outside we're at risk, unfortunately," said Simser. Because nymphs are the size of poppy seeds, they often go undetected. Simser advises people to inspect themselves regularly. Feel behind your neck, and ears, and under your hair.

"You might think you have a little pimple, it may be a tick," he said.

State Rep. Shirley Gomes said people used to try to hush up the Lyme disease problem on Cape Cod for fear of discouraging tourism. That not so anymore, she said at the task force's fifth annual physicians forum in Hyannis last week. Over the past few years, she said, attitudes have changed.

"Overall people are very interested in letting people know that even in our utopia there are a few glitches," said Simser.