Babesia: What Lyme Patients Need to Know | Dr. Daniel Cameron
Babesia pregnancy risk is real and underrecognized. In this Inside Lyme case study, I discuss two mothers who unknowingly passed this tick-borne parasite to their babies.
Saetre and colleagues first described these cases in the Journal of the Pediatric Infectious Disease Society in 2017.
This parasite can be contracted from the bite of a deer tick, a blood transfusion, or during pregnancy. The CDC recognizes that transmission can occur in utero. In this case study, the infection was transmitted from the mothers to their babies during pregnancy.
I discussed this paper from the baby’s perspective in an earlier Inside Lyme podcast titled – Two children who contracted this infection from their mothers.
In this podcast, I will be focusing on the mothers.
First Mother with Babesia Pregnancy
The first mother lived in Westchester County, New York, an area endemic for Lyme disease. I live and practice medicine in the same county.
The mother was diagnosed with Lyme disease in her third trimester at 32 weeks gestation. She presented with an erythema migrans rash (EM).
She was treated with amoxicillin. Amoxicillin has been commonly prescribed during pregnancy. I use amoxicillin for pregnant women in my practice.
I use other antibiotics, e.g., azithromycin. I work with my patient’s obstetrician as needed.
I advise mothers that neither amoxicillin nor azithromycin is effective against other common tick-borne infections such as Ehrlichia, Anaplasmosis, and this parasite.
I advise my patients to return for follow-up to ensure their Lyme disease has been successfully treated and to reassess for evidence of Ehrlichia, Anaplasmosis, or this co-infection.
The doctors followed the mother. The mother was positive by IgM laboratory testing two weeks after her diagnosis of Lyme disease. A positive IgM test would be consistent with an early infection. I would have treated the mother.
The mother was not treated. The mother and her baby boy went home.
The mother’s baby boy was diagnosed and treated 4 ½ weeks after going home.
The mother was again positive. The tests were now positive by an IgG western blot. The conversion from a positive IgM western blot test to a positive IgG western blot test was further evidence that the mother contracted this infection during her third trimester. I would still have treated the mother.
Again the mother was not treated—an example of how tick-borne infections get dismissed even with clear evidence.
Second Mother with Babesia Pregnancy
The second mother lived in Putnam County, New York, an area endemic for Lyme disease. Putnam County is located just north of Westchester County.
The mother initially had muscle soreness and a fever for two weeks. The mother was diagnosed with Lyme disease in her third trimester at 37 weeks gestation. She presented with an EM rash.
She was treated with amoxicillin.
The mother’s laboratory tests for a tick-borne infection were not positive at the time of her EM rash.
Her baby girl was tested after delivery. Her girl’s blood test was positive for Babesia microti by PCR. The doctors did not look for the parasite in her baby girl’s red blood cells under the microscope. The doctors concluded that the baby girl showed no symptoms. Her baby girl was not treated.
The mother and her baby girl went home.
Her baby girl had evidence of this parasite in her red blood cells when she was 18-days-old. Her girl was hospitalized and treated with a series of antibiotics, antiparasitic medications, and a blood transfusion.
The mother’s blood tests were now positive by PCR, IgM, and IgG tests. The conversion from a positive IgM western blot test to a positive IgG Western blot test was further evidence that the mother contracted this infection during her third trimester.
The mother was not treated. The baby girl was.
What Can We Learn from These Babesia Pregnancy Cases?
- Women can contract this parasite during their pregnancy.
- Pregnant women can transmit the infection to their babies in utero.
- There can be a delay in the onset of symptoms after contracting Lyme disease. In these cases, the co-infection occurred weeks after the mother contracted Lyme disease.
Questions These Cases Raise
- How often do mothers contract this parasite during their pregnancy from a tick bite?
- Is there an effective and safe treatment for a pregnant woman?
- How does a mother or doctor recognize this infection in a pregnant mother?
- Should doctors follow pregnant mothers with a tick bite or Lyme disease for this co-infection? I follow a mother and their child for evidence of it.
- Should the two mothers have been treated?
- Will the mothers develop complications in the future if not treated?
Treating Tick-Borne Disease in Pregnancy
We need more doctors with skills diagnosing and treating this infection in children and their mothers. We need to determine the best course of treatment for pregnant women and their children. We hope that if a professional sees a pregnant woman with a tick-borne illness that they can use these cases to remind them to look for this parasite and treat accordingly.
Babesia pregnancy transmission is preventable when doctors recognize the risk. Mothers with persistent symptoms after Lyme treatment should be evaluated for this co-infection—especially if symptoms appeared during pregnancy.
If you’re pregnant and have been bitten by a tick or diagnosed with Lyme disease, ask your doctor about screening—it could protect you and your baby.
References
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.