Lyme Disease: What To Know This Season
Editor's note: This article was updated on Aug. 15, 2017.
As Lyme disease cases increase in the U.S., a vaccine could be on the way.
The FDA in July gave "fast-track" approval to test potential Lyme disease vaccine VLA15 on adults in the U.S. and Europe. The designation helps speed drugs and vaccines to market more quickly.
There is currently no vaccine to prevent the disease, the most common vector-borne illness reported in the U.S. Cases have been trending upward, more than doubling nationwide between 1995 and 2015. The ticks that spread it continue to show up in new areas, experts say.
“I think we’ll just keep seeing more and more,” says John Aucott, MD, director of the Johns Hopkins Lyme Disease Clinical Research Center.
Although most cases are still reported in the Northeast, the black-legged tick -- also known as the deer or bear tick -- has been found as far south as Florida and as far north as Canada, data from the CDC show.
For most people, the disease causes flu-like symptoms. About 80% of people who get it fully recover by taking antibiotics, the CDC says.
Here’s more about the disease and what to expect this year and beyond.
What is Lyme disease?
Lyme disease is caused by a bacteria, Borrelia burgdorferi, that’s transmitted to humans through a bite from an infected black-legged or deer tick. Symptoms can occur anywhere from 3 to 30 days after the bite, and symptoms can be wide-ranging, depending on the stage of the infection.
The chances you might get Lyme disease from a tick bite depend on the kind of tick, where you were when the bite occurred, and how long the tick was attached to you, according to the CDC. Black-legged ticks must be attached to you for at least 24 hours to transmit Lyme disease.
What are the symptoms of Lyme disease?
Early signs and symptoms of Lyme disease include fever, chills, headache, fatigue, muscle and joint pain, and swollen lymph nodes, the CDC says.
In about 70% to 80% of infections, a rash is seen. About 30% of those rashes have a “bull's-eye” appearance, but most do not, Aucott says. “It’s uniformly round and red” or bluish-red, he says.