摘要：National Institutes of Health researcher Willy Burgdorfer identified the culprit in 1982: a spirochete bacterium that, in electron micrograph images, resembles a broken twist of barbed wire.2 The spirochete, named Borrelia burgdorferi (Bb), was first isolated from the gut of ticks collected in woodlands on Shelter Island, New York, where Lyme disease had become endemic. Thirty years after its discovery, Lyme disease has become by far the most common vectorborne infection in North America.3 Today the ecology of Bb is the subject of both intense study and intense scientific debate. Some researchers think that protecting large tracts of forest habitat—a strategy that increases the diversity of vertebrate hosts for both Bb and its tick vectors—will ultimately reduce the risk of human infection. Others argue that there is no predictable relationship between host biodiversity and human disease risk.
