The epidemiology of lyme borreliosis.

The tick-transmitted bacterial infection known as Lyme disease, or Lyme borreliosis, has recently emerged as the leading arthropod-borne disease in Europe and North America. Several thousand new cases of human Lyme disease are reported each year from Europe and the USA. The causative agent, Borrelia burgdorferi, has been isolated from several species of mammals, birds, ticks and insects and, in this article, Thomas Jaenson discusses the geographical differences in the epidemiology of the infection.