Ick, a tick! Many people are familiar with Lyme disease because it is endemic in our area. Lyme disease is an infection caused by the bacteria Borrelia burgdorferi. In Northern Virginia, this infection is spread by the black-legged or deer tick. These ticks are a particular nuisance because of their small size. In people, they are often mistaken for a freckle or a mole, and in our furry friends they may be overlooked entirely. Once these ticks attach and feed, they can transmit the Lyme bacteria through their saliva. Within our practice, about 25% of unvaccinated dogs will be exposed to the Lyme disease causing bacteria, but a much smaller percentage will develop clinical Lyme disease.