St Hubert’s Key took the form of a metal nail or bar with a decorative head. It was used in Europe until the early 20th century as a traditional cure for rabies and was named for St Hubert, the patron saint of hunters, mathematicians, opticians and metalworkers.
The key was heated and the head pressed to the area where a person had been bitten by a dog believed to have rabies. If performed soon after the bite had occurred, the heat had the potential to cauterize and sterilize the wound, killing the rabies virus.[1] The practice was endorsed by the Catholic Church and such keys were used by priests at places with which St Hubert was associated, where the skin of humans and animals was branded as a protection against the bites of rabid dogs.[2] This practice is recorded in the 1870s in the Ardennes region, France, where dogs were branded with St Hubert's Key, as "a sure preventative of madness".[3]