Lone star tick that triggers red meat allergy spreading across US

A tick which causes an unusual allergy to red meat seems to be spreading.

The lone star tick, named for a spot on its back, used to be limited to eastern and southeastern states, but it's now showing up in Minnesota, Missouri, and eastern Long Island.

The allergy is hard to pin down because the reaction can be delayed.

"People have gone weeks to months trying to figure out what is causing the reaction, because it happened so far away from when they ate the food," said Dr. Christine Franzese of the University of Missouri.

When lone star ticks bite, they can transfer a sugar called alpha-gal.

People develop antibodies to it and then have severe reactions when they eat meat.

The only known treatment is to avoid meat until the allergy goes away, which can take years.
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