Lyme disease may hide in healthy-looking birds until the stress of migration drives it into a potentially infectious state, warn Swedish researchers.
According to this new scenario, migratory birds could be powering more of the spread of Lyme disease than expected, suggests Björn Olsen of Umeå University in Sweden. He and his colleagues describe the migratory flare-up of Lyme disease in the Feb. 17 Nature.
Since 1975, the disease has grown from a local medical puzzler in Lyme, Conn., to what the Centers for Disease Control and Prevention calls "an important public health problem." The more than 10,000 U.S. cases reported annually cluster in the Northeast, in north-central states, and on the West Coast. Now that doctors know what to look for, they recognize the disease in temperate regions of Asia and Europe.
Lyme disease often begins with a circular skin rash, followed by a nasty mix of flu and arthritis symptoms.