Lyme disease is caused by the bacterium Borrelia burgdorferi, transmitted through the bite of an infected deer tick, also known as a black–legged tick. Unlike common wood ticks or dog ticks, these deer ticks carry the bacteria responsible for Lyme disease. The disease was first identified in Lyme, Connecticut, in 1975, following an unusual spike in juvenile rheumatoid arthritis cases. Researchers discovered that these cases were linked to tick bites from infected deer ticks.
Today, Lyme disease is the most rapidly increasing vector–borne illness in the United States, with an alarming rate of new cases. On average, 34 new cases are reported every hour, turning to 882 cases per day and over 25,000 cases per month. Despite this, diagnosing Lyme disease remains challenging.