A steak may never seem as appetising again after a tick bite, warn researchers.
Being bitten by one of the spidery creatures can trigger a severe allergy to meat, scientists have learned.
Three cases of the strange reaction were identified in the US. The patients suffered severe symptoms several hours after eating red meat.
Experts traced the delayed allergic response to bites from a tick - specifically the Lone Star tick.
A carbohydrate compound injected into the bloodstream by the bite is also present in meat. The initial bite is thought to prime the immune system to react next time it encounters the substance.
The result when the unsuspecting victim tries tucking into a steak can be an outbreak of hives, or even life-threatening anaphylactic shock.
Dr Susan Wolver, from Virginia Commonwealth University, and colleagues described the research in the Journal of Internal Medicine.
They wrote: "Where ticks are endemic, for example in the south-eastern United States, clinicians should be aware of this new syndrome when presented with a case of anaphylaxis. Current guidance is to counsel patients to avoid all mammalian meat - beef, pork, lamb and venison."