Lyme Disease
Description
Lyme disease results from infection with spirochetes
belonging to the Borrelia burgdorferi sensu lato complex.
In Europe and Asia, most cases of Lyme disease are caused by B.
burgdorferi sensu stricto, B. afzelii, or B. garinii;
however, in the United States, all cases are caused by B. burgdorferi sensu
stricto. The spirochetes are transmitted to humans through the bite
of infected ticks of the Ixodes ricinus complex.
Occurrence
Lyme disease occurs in temperate forested regions
of Europe and Asia and in the northeastern, north central, and Pacific
coastal regions of North America. It is not transmitted in the tropics.
Risk for Travelers
Travelers to endemic areas who have frequent or
prolonged exposure to tick habitats could be at increased risk for
Lyme disease.
Clinical Presentation
Manifestations of Lyme disease include a characteristic
expanding rash called erythema chronicum migrans at the site of tick
attachment, fever, arthritis, and neurologic manifestations, including
facial palsy.
Prevention
Vaccine
A safe and efficacious vaccine was, until recently,
available for protection from Lyme disease in endemic areas of the
United States. However, the vaccine was withdrawn from the market
by the manufacturer in February 2002 because of low sales and is
no longer commercially available.
Other
Travelers to endemic areas should be advised to
avoid tick habitats if possible. If exposure to tick habitats cannot
be avoided, the application of repellents to skin and acaricides
to clothing, as well as regular daily checks for any attached ticks,
can reduce the risk of infection. Because transmission of B. burgdorferi is
unlikely to occur in the first 36 hours of tick attachment, prompt
removal of any attached ticks will help prevent infection.
Treatment
Travelers who have erythema chronicum migrans or
other manifestations of Lyme disease should be advised to seek early
medical attention. Lyme disease can usually be cured by an appropriate
course of antibiotic treatment.
— Edward
Hayes
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