Rochester, MN (Learfield Wire Services) -- Mayo Clinic researchers have discovered a new species of bacteria that causes Lyme disease in humans.

The Centers for Disease Control and Prevention has announced the discovery of the Borrelia mayonii. Previously, there was only one other type of bacteria thought to cause Lyme disease in North America.

Mayo Clinic scientists say the lab test results from six people with suspected Lyme disease produced “unusual results,” which prompted the investigation that led to the discovery of the second bacterial species. It is related to first microbe linked to Lyme disease and also causes a fever, headache, rash, neck pain and arthritis. Mayo researchers say the new bacteria is also associated with nausea and vomiting, a different type of rash and a higher concentration of bacteria in the blood.

It’s believed to be transmitted by deer ticks.