A New Strain of Lyme
The old bug has acquired a sibling, but the message is the same: be careful outdoors
It’s a familiar public-service warning: if you plan to be in grassy or wooded areas this spring or summer, wear long sleeves and pants so you don’t become one of the roughly 23,000 Americans who are diagnosed with Lyme disease each year. This illness is transmitted by a bite from a black-legged tick (also known as a deer tick) and caused by a bacterium of the Borrelia genus. In the U.S. that strain is usually Borrelia burgdorferi. But a new and as yet poorly understood strain called Borrelia miyamotoi, named for its Japanese discoverer, has been uncovered, thanks in part to physicians on staff at Westchester Medical Center.
“We provided the blood samples to Yale University to help prove there was another infection type,” says Gary Wormser, M.D., Chief of the Medical Center’s Division of Infectious Diseases, co-author of the report published in the January 2013 New England Journal of Medicine. “This is the first verified report of the new infection in the United States, and it was found right here in Westchester County.”
The bacterial cause of the infection is known, but “we still have a lot to learn about this—what symptoms it causes, how to diagnose it and how to treat it,” Dr. Wormser says. Reports out of Russia, where it has also been seen, reveal that the bacterium caused only fever, he says, and that antibiotics were effective in killing the bug.
Prevention pointers are the same as for other strains of Lyme, says Dr. Wormser. Do a tick check within 24 hours of going outdoors in an environment where there are ticks—including front and backyards. If you find a tick, remove it as quickly as possible. “Lyme bacteria are transmitted slowly, and usually the tick needs to be attached to you for 48 hours before the bacteria enter your bloodstream,” he says. Use tweezers to gently pull it off, and save the tick in any container. “There’s no need to save it in alcohol, and a plastic bag will do,” he says.
You can bring the tick to the Lyme Disease Diagnostic center for free testing to see if it is the kind of tick that carries Lyme or the new Borrelia bacteria. “We have a system that’s only available here to evaluate the tick, and we can even determine—to the hour— how long the tick was on your body,” says Dr. Wormser. “If it was on at least 36 hours, we offer a single dose of an antibiotic, usually doxycycline. That will help to prevent Lyme disease.”
To learn more, or to arrange to bring a tick to the lab, call the Lyme Disease Diagnostic Center at 914.493.TICK (8425). —D.L.