Delayed babesia is a concept that could explain why some Lyme disease patients relapse after initially improving with antibiotics. In this case, a 67-year-old woman developed a Babesia infection 3 weeks after treatment for Lyme disease—raising important questions about how we evaluate and follow these patients.
Hoversten and colleagues first discussed this case in the British Medical Journal Case Reports in 2018.
The Case: Delayed Babesia After Lyme Treatment
A 67-year-old woman from Wisconsin had extensive tick exposure as an avid gardener who spent considerable time outdoors. She did not see a tick, but she did see a rash consistent with erythema migrans.
She was prescribed amoxicillin for three weeks as she was allergic to doxycycline.
Near the end of her three-week course of amoxicillin, she became ill. Her fever rose to 102.9°F. She complained of myalgias, dizziness, and fatigue.
Her blood test showed mild anemia, a low platelet count and neutrophil count, and a very high C-reactive protein. She was admitted to the hospital. The doctors thought she might be suffering from sepsis or a tick-borne infection.
Her red blood count and platelets continued to drop. She was transferred to a second hospital. There was no evidence of sepsis—blood cultures were negative after five days.
Diagnosing Delayed Babesia
She was diagnosed with the parasite Babesia microti by PCR and by a thin smear of her red blood cells. In her case, 0.4% of her red blood cells showed the parasite on a thin smear.
Babesia infections can be severe and, in rare cases, life-threatening. This woman was at higher risk because she was over 50 years of age and had a history of colon cancer.
She was prescribed a 10-day course of azithromycin and atovaquone. By the 5th day of treatment, her fever had resolved, and her platelet count had more than doubled from a low of 17,000 per dl to 42,000 per dl.
The authors report that the woman remains fatigued after completing treatment—consistent with what we see in patients with persistent symptoms.
Why Delayed Babesia Matters
The authors discussed the nearly three-week gap between the woman’s erythema migrans rash and her diagnosis of Babesia. This is not the first case where the onset of Babesia was delayed.
The authors cited two papers describing a 3 to 4-week delay in the onset of Babesia. I described a similar pattern in an earlier podcast where two babies contracted Babesia from their mothers—they did not present with Babesia until after being discharged from the hospital.
This delay may explain why some Lyme disease patients relapse after initially improving with doxycycline or amoxicillin. Treatment for Lyme disease with doxycycline or amoxicillin is not effective for the treatment of Babesia.
Key Takeaways
- Babesia infections can occur weeks after the onset of Lyme disease
- Standard Lyme treatment (doxycycline, amoxicillin) does not treat Babesia
- Delayed babesia may explain why some patients relapse after initial improvement
- Patients with Lyme disease should be advised to return for follow-up if symptoms recur
Frequently Asked Questions
Can Babesia appear weeks after a tick bite?
Yes. Delayed babesia can present 3-4 weeks after initial Lyme disease symptoms, even after Lyme treatment has ended.
Why doesn’t Lyme treatment work for Babesia?
Lyme disease is caused by bacteria treated with doxycycline or amoxicillin. Babesia is a parasite that requires different medications—typically atovaquone and azithromycin.
Could this explain why some Lyme patients relapse?
Yes. If Babesia is present but undiagnosed, patients may initially improve on Lyme treatment, then relapse when the delayed Babesia symptoms emerge.
Should Lyme patients be tested for Babesia at diagnosis?
Given the frequency of co-infections, testing for Babesia at the time of Lyme diagnosis—especially in endemic areas—is reasonable.
What are the symptoms of delayed Babesia?
Fever, fatigue, myalgias, dizziness, anemia, and low platelet count—often appearing after Lyme treatment has concluded.
References
- Hoversten K, Bartlett MA. Diagnosis of a tick-borne coinfection in a patient with persistent symptoms following treatment for Lyme disease. BMJ Case Rep. 2018.
- Saetre K, Godhwani N, Maria M, et al. Congenital Babesiosis After Maternal Infection With Borrelia burgdorferi and Babesia microti. J Pediatric Infect Dis Soc. 2017.
I was just diagnosed with Lyme disease and I think I have had it for a long time. I had been bitten by a tick in early spring but my doctor was not worried and never ordered test. I became extremely ill. Fatigued, nauseous, just didn’t feel good. I soon started getting these spells where I would suddenly feel like I was going to pass out, then I would start dry heaving and then I would be okay. Then suddenly it would happen again. I went to emergency room with pain in my left arm left chest and jaw and they did a bunch of bloodwork. My potassium was down to 2.4 and they said that was the cause and gave me potassium. After some time I felt somewhat better and thought I would be ok. About 3 months later it all began again, my potassium was low again despite my being on supplements daily since the first time. After about two weeks I felt again somewhat better but not normal. Still suffering from fatigue and swelling in my leg so bad that at times I could barely walk. About a month ago I began having massive pain in my legs but it felt like it was deep. My leg muscles ached so bad that it’s hard to even stand up. I went to get my knee checked out but my other leg had swollen to about three times it’s normal size and the pain in my muscles and joints was beyond anything I have ever felt. The doctor ordered a test for Lyme disease and it was positive. I am now on doxycycline and it’s been a week with no changes in swelling or symptoms. How long before I start feeling better? The pain is debilitating, the swelling is still massive dispute taking ibuprofen and Tylenol and I am not able to take anything else for the pain because I have had a previous issue with opiates and have been in recovery for years and doing great. I already suffer with chronic depression and this doesn’t help. The pain is so bad and I don’t know what to do at this point I’ve been sick for months with short spirts of feeling okay. Please help me to understand what could be happening
I have Lyme disease patients with similar stories. I don’t typically see much change after a week of doxycycline if one had been ill for a long time. I have seen Lyme disease increase pain even from old injuries. I also advise my patients to work with other specialists to rule out other causes of illness.