This year's mild winter and early spring were a bonanza for tick populations in the eastern United States. Reports of tick-borne disease rose fast.
While Lyme disease is the most common tick-borne disease in the Northeast and Upper Midwest, new research results emphasize that it is not the greatest cause for concern in most Southeastern states.
The findings are published today in a paper in the journal Zoonoses and Public Health.
The majority of human-biting ticks in the North--members of the blacklegged tick species--cause Lyme disease, but these same ticks do not commonly bite humans south of mid-Virginia.
Biologist Graham Hickling of the University of Tennessee, co-author of the paper, says many patients in Southeastern states, who become sick from a tick-bite, assume they have Lyme disease, but the odds of that being the case are low.
"Ticks in the eastern U.S. collectively carry more than a dozen agents that can cause human disease," says Hickling.
"Here in Tennessee we regularly collect lone star ticks that test positive for Ehrlichia, [a tick-borne bacterial infection]. Lone stars are an aggressive species that account for most of the human bites that we see in this region. So ehrlichiosis has to be a big concern, yet most people have never heard of it."
In contrast, says Hickling, there have been no confirmed reports to date of the Lyme disease pathogen among the sparse populations of blacklegged ticks found in Tennessee.
"The Southeast is dominated by different tick species than the ones that attack humans in the North," says Ellen Stromdahl, an entomologist at the U.S. Army Public Health Command and lead author of the paper.
"The lone star tick is by far the most abundant tick in the Southeast, and which species of tick bites you is critical because different ticks carry different diseases. In the Southeast you are unlikely to be bitten by the blacklegged ticks tha
|Contact: Cheryl Dybas|
National Science Foundation