Lyme disease is caused by spiral-shaped bacteria known as 'Borrelia burgdorferi'. They are spread from one animal to another by tick bites and can be transmitted to people when a tick feeds on an infected animal, then goes on to bite a human. The infection is not transmitted directly from person-to-person, or from other animals.

Woodland, heath land or occasionally parkland areas where deer live, are the most likely places to catch Lyme disease. The risks are higher if you are working, camping or involved in outdoor activities in these areas. The most likely time to be infected is in late spring, early summer or autumn.