Can a tick bite turn you off red meat for good?
It can if it is the bite of a Lone Star tick, a type that's endemic in the southeastern United States. This phenomenon has been known for a while, but now new research published online July 20 in the Journal of General Internal Medicine reports on three case studies to illustrate exactly how it may occur.
The Lone Star tick injects spit into a person's body when it bites. The body then develops antibodies in response to a carbohydrate called alpha-gal that is present in the spit. This carbohydrate substance is also present in red meat. When the bitten person eats meat again, their immune system goes on the warpath, causing an allergic reaction. This reaction is typically delayed, occurring about three to six hours after eating meat.
The reaction can range in severity from mild hives and itching to full-blown anaphylactic shock, according to Dr. Susan Wolver and Dr. Diane Sun at the Virginia Commonwealth University, in Richmond.
This connection was first discovered somewhat serendipitously by researchers who were trying to determine why a cancer drug called cetuximab (Erbitux) was causing severe allergic reactions in people in the southern states. The sugars in Erbitux are also present in beef, pork and cows' milk.
Calling the phenomenon "the cow's revenge," Dr. Bruce Hirsch, an infectious diseases specialist at North Shore University Hospital in Manhasset, N.Y., said, "Lone Star tick bites may well be turning a portion of people in the southeast into involuntary vegetarians."
Tick bites cause a host of other diseases and infections including Lyme disease and Rocky Mountain spotted fever. The best thing to do is to avoid ticks altogether, Hirsch said. For starters, avoid wooded and bushy areas with high grass and use insect repellents that contain 20 percent or more DEET (N, N-diethyl-m-toluamide) on all exposed skin.
Dr. Bernard Feigenbaum, an allergist at the NYU Langone Medical Center in New York City, said that most people think about Lyme disease when they think about ticks and tick bites . "This study shows that there can be other allergic consequences," he said. "If a person discovers having reactions or unusual symptoms after eating meat, follow up with a primary care doctor or an allergist to see what is going on."
If you are allergic to red meat, you will need to avoid beef, pork, lamb, venison and other meat from mammals, said Despina Hyde, a nutritionist at the NYU Langone School of Medicine. "Poultry, fish and chicken are OK."
(SOURCES: Bernard A. Feigenbaum, M.D., allergist, NYU Langone Medical Center, and clinical assistant professor of medicine and otolaryngology, NYU Langone School of Medicine, New York City; Despina Hyde, M.S., nutritionist, NYU Langone Weight Management Program, New York City; Bruce Hirsch, M.D., infectious diseases specialist, North Shore University Hospital, Manhasset, N.Y.; July 20, 2012, Journal of General Internal Medicine, online)
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