What you need to know about Borrelia mayonii
What is Borrelia mayonii?
Borrelia mayonii are a type of bacteria recently found in North America that can cause Lyme disease. These bacteria are different from the three types of bacteria that cause most cases of Lyme disease worldwide.
- Borrelia burgdorferi (North America, Europe)
- B. afzelii (Europe, Asia)
- B. garinii (Europe, Asia)
B. mayonii is the only species besides B. burgdorferi shown to cause Lyme disease in North America.
How was it discovered?
In 2013, scientists at the Mayo Clinic noticed an unusual result while testing blood from patients who were thought to have Lyme disease. Cooperation between Mayo Clinic, state public health agencies, and CDC confirmed that a new type of bacteria that infects people had been found in blacklegged ticks.
Where does B. mayonii occur?
Current evidence suggests that within the United States, B. mayonii is only found in the Upper Midwest.
Has B. mayonii been found in ticks?
Yes, but not as often as B. burgdorferi. B. mayonii has been found in blacklegged ticks collected in northwestern Wisconsin and Minnesota. The blacklegged tick can also transmit B. burgdorferi (the bacteria that causes almost all Lyme disease infections in the United States), and the germs that cause anaplasmosis, babesiosis, and Powassan virus disease.
What type of illness does B. mayonii cause?
Based on limited information, illness caused by B. mayonii appears similar to that caused by B. burgdorferi, but with a few differences. Like B. burgdorferi, B. mayonii causes fever, headache, rash, and neck pain in the days after infection and can cause arthritis after a few weeks of illness. Unlike B. burgdorferi, B. mayonii can also cause nausea and vomiting; large, widespread rashes; and a higher concentration of bacteria in the blood.
What tests are used to diagnose B. mayonii?
Your healthcare provider may order a blood test to look for infection. Limited available information suggests that patients with B. mayonii infection develop antibodies that are similar to those of patients infected with B. burgdorferi. Therefore, Lyme disease serologic testing may help in diagnosing patients with B. mayonii. In some cases, B. mayonii bacteria may also be seen on a blood smear. Infection with B. mayonii can be specifically identified by Lyme disease molecular tests at Mayo Clinic. Lyme disease, including infection with B. mayonii, can be diagnosed without testing when patients have signs and symptoms consistent with Lyme disease and a history of possible exposure to blacklegged ticks.
How is B. mayonii treated?
Physicians have successfully treated patients infected with B. mayonii with a 2- to- 4-week course of doxycycline. Other antibiotics that are often used to successfully treat Lyme disease can also be used.
Why are we just discovering this now?
It is possible that the bacteria recently emerged or that the bacteria have been present in the area for a long time but hadn’t been discovered. Mayo Clinic tested roughly 100,000 patient samples in the same way for over a decade but only recently detected B. mayonii.
I live in the northeastern United States where Lyme disease is common. Should I be worried about B. mayonii?
At this time, there is no evidence that B. mayonii is found outside of the Upper Midwest. However, you should continue to take precautions against tick bites as Lyme disease, anaplasmosis, and babesiosis are common in much of the Northeast.
What more do researchers need to know?
CDC, Mayo Clinic, and the Minnesota Department of Health continue to test blood samples from patients suspected of tickborne illness, like Lyme disease, to learn more about tickborne bacteria that may cause human illness.
In addition, biologists continue to collect and test ticks throughout the United States to determine the range of the ticks that are infected with these bacteria.
How can I avoid this disease?
For more information, see Preventing Tick Bites.