Scientists say the new species of Lyme-carrying bacteria was discovered in the blood of a half-dozen patients with suspected tick-borne illnesses.

A new species of bacteria has been discovered that can cause Lyme disease in people.

The new bacteria is only the second species ever identified that is capable of transferring the disease from ticks to humans.

It was discovered when scientists at the Mayo Clinic in Minnesota noticed something unusual in the blood of six people with suspected Lyme disease, according to an announcement today from the Centers for Disease Control and Prevention (CDC).

The findings were published in The Lancet.

The new bacteria was identified in ticks in two counties in northwestern Wisconsin. Scientists say the likely exposure area is in north central Minnesota and western Wisconsin.

The bacteria was not found in 25,000 blood samples taken from people with suspected tick-borne diseases in 43 other states between 2012 and 2014.

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The new bacteria is named B. mayonii.

Scientists say it’s similar to B. burdorferi, the only other bacteria to date known to cause Lyme disease in humans. Nonetheless, there are some differences.

Both species can cause fever, headache, rashes, and neck pain in early stages of infection. The disease can cause arthritis in later stages.

However, scientists said it appears that B. mayonii can also cause nausea and vomiting. It may also create a mixture of rashes unlike B. burdoferi, which produces a distinct bulls-eye rash.

B. mayonii is apparently found in higher concentrations in the blood, too.

Both are believed to be caused by the bite of an infected black-legged (or “deer”) tick.

“This discovery adds another important piece of information to the complex picture of tick-borne diseases in the United States,” Dr. Jeannine Petersen, a CDC microbiologist said in a statement.

Scientists say both strains of Lyme disease can be treated with the same antibiotics.

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CDC officials said they are working closely with state health officials in Minnesota, North Dakota, and Wisconsin to better understand the new species of bacteria.

In 2015, the CDC funded a partnership with health officials in Minnesota and Tennessee as well as the Mayo Clinic and Vanderbilt University to screen 30,000 specimens over a three-year period from people with suspected tick-borne illnesses.

The CDC utilizes advanced molecular detection methods to test the specimens for other bacteria causing the diseases.

“CDC is investing in advanced technology to bring study of tick-borne infections into a new era,” said Ben Beard, Ph.D., chief of the CDC’s Bacterial Diseases Branch. “Coupling technology with teamwork between federal, state, and private entities will help improve early and accurate diagnosis of tick-borne diseases.”

To reduce tick-borne illnesses, health officials advise that people:

  • Avoid wooded and brushy areas.
  • Use insect repellent when outdoors.
  • Conduct a full-body tick check after spending time outdoors.
  • Bathe or shower as soon as possible after coming indoors.
  • Examine gear and pets as ticks can come into a house on these and then attach to humans.

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