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Home Topics Infectious Diseases Infections A-Z Lyme borreliosis / Lyme disease

Lyme borreliosis / Lyme disease

Tick on finger nail

Lyme borreliosis (or Lyme disease) is an infectious disease caused by the bacterium Borrelia burgdorferi. Lyme disease was named after a cluster of cases that occurred in Old Lyme, Connecticut in the United States, in 1974. The disease may have various symptoms, the most common being a rash called erythema migrans.

Human beings become infected after being bitten by hard-bodied ticks ( Ixodes species ) that are infected with B. burgdorferi. Ticks become infected when they feed on birds or mammals that carry the bacterium in their blood.