Under attack: Researchers shed light on how Lyme disease infects the body

The findings could better inform treatment options and help prevent severe outcomes of the disease. A tick reaches for a human arm An estimated 476,000 Americans are infected each year with Lyme disease, a condition causing a wide range of symptoms that include fever, rash, and joint pain, as well as effects on the central nervous system and heart. Though it's common knowledge that Borrelia burgdorferi -the bacteria that causes the disease-enters the body through the bite of an infected deer tick, how the bacteria manages to migrate from that bite into a person's bloodstream has not been clearly understood. Johns Hopkins engineers may have found the answer. Using a custom designed three-dimensional tissue-engineered model, they learned that B. burgdorferi uses tenacious trial-and-error movements to find and slip through tiny openings called junctions in the lining of blood vessels near the original bite site. This allows them to hitch a ride on the bloodstream throughout the body, potentially infecting other tissue and organs. Their results appear today in Advanced Science .