|Articles|February 10, 2016

There's a New Bacteria Species Causing Lyme Disease

Up until now, B. burgdorferi was the only species of bacteria believed to cause the tick-borne illness.

It was discovered in 1981 that the bacteria Borrelia burgdorferi (B. burgdorferi) causes Lyme disease. Up until now, this was the only species of bacteria believed to cause the tick-borne illness.

When six patients were tested for Lyme disease and produced unusual results, it was suspected that a new bacteria was the culprit. Genetic testing conducted at the Mayo Clinic and Centers for Disease Control and Prevention (CDC) revealed that the bacteria (provisionally named) Borrelia mayonii (B. mayonii) also causes Lyme disease in humans. The new species is closely related to B. burgdorferi.

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

Lyme disease causes a wide range of symptoms. In the early stage of B. burgdorferi (three to 30 days after tick bite), fever, chills, headache, fatigue, swollen lymph nodes, and muscle and joint aches are common. About 70% to 80% of patients develop an erythema migrans (EM) rash. In the later stage, patients can develop severe headaches, neck stiffness, EM rashes, nerve pain, shortness of breath, short-term memory problems, and even arthritis. These symptoms have also been observed in those with B. mayonii. However, this new bacteria is also associated with nausea, vomiting, and diffuse rashes as opposed to a single rash which looks like a bull’s-eye. There is a higher concentration of the bacteria in the blood as well, according to the report in The Lancet Infectious Diseases.

The six patients with the new Lyme strain were successfully treated with antibiotics that are used for illness caused by B. burgdorferi. Fortunately it appears that current Lyme treatments also fight B. mayonii.

The new Lyme-causing bacteria has only been found in the upper Midwest so far. Therefore, a limited amount of information is available at this time. But discoveries such as this one give health care providers the opportunity to catch the illness faster to avoid the more serious symptoms.

“Coupling technology with teamwork between federal, state, and private entities will help improve early and accurate diagnosis of tick-borne diseases,” said Ben Beard, PhD, chief of CDC’s Bacterial Diseases Branch.

The CDC recommends the following steps to reduce the risk of tick bites that can lead to diseases:

  • Avoid wooded areas and high grass
  • Use insect repellent when outdoors
  • Spray clothing with permethrin products
  • Bathe as soon as possible after being in risky areas
  • Do a full body check for ticks after being outdoors
  • Check pets and gear that ticks could have latched onto

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