My father was diagnosed with early stage Lyme disease this morning, so in honor of him I want to talk a little bit about Borelia burgdorferi.

Lyme disease was described a few decades before the cause was known. The present form became studied after outbreaks occured in the area around Lyme, Connecticut, giving the disease its popular name.

B. burgdorferi is a spirochete bacteria, meaning that it has a helical coiled shape. It was first identified by Jorge Benanch, of the State University of New York at Stony Brook, who developed the first critical ELISA antibody test that could test for the presence of the bacteria. Dr. Benanch just so happens to also be the boss of my department and his wife was one of my high school biology teachers (now there’s something wikipedia can’t tell you). Soon after it was isolated by Willy Burgdorferi, for whom the bug was named.

The life cycle of Borrelia is interesting because they require ticks for transmission and mammals to feed on. Tick larvae become infected with Borrelia during the larvae or nymph stage when they feed on white-footed mice. Borrelia remains in the tick as it advances in its life cycle to adult. The adult ticks then feed on small mammals or humans, transmitting the spirochete where (in humans and dogs) it can become pathogenic. However adult ticks preferentially feed on white-tailed deer (no immediate relation to white-footed mouse) and is the source of the name ‘deer tick.’ The adult tick has to feed on deer blood for at least three days in order to be able to reproduce. Borrelia is nonpathogenic to deer.

This is an interesting commensal/parasitic relationship between these three organisms. The ticks rely on deer and Borrelia relies on the ticks. They are barely aware of the others existence, yet they have evolved together in a unique sort of hierarchy.

This entry was posted on Friday, March 21st, 2008 at 8:37 pm and is filed under evolution, microbiology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.