West Wake News

Researchers from North Carolina State University have reported a case study in which Bartonella henselae, Babesia odocoilei, and Babesia divergens-like MO-1 DNA were found in brain tissue samples of a child experiencing seizures and suspected Rasmussen’s encephalitis. This discovery adds to the evidence suggesting that these pathogens can be involved in complex neurological conditions.

Bartonella species are vector-borne bacteria mainly transmitted by arthropods such as fleas, lice, and possibly ticks. Among the 45 known Bartonella species, 18 can infect humans. Bartonella henselae is widely recognized for causing cat scratch disease.

Advancements in detection methods have improved diagnosis of bartonelloses in patients with chronic illnesses and psychiatric symptoms.

Babesia is a protozoa similar to malaria that infects red blood cells. In the U.S., B. microti, B. duncani, and B. divergens-like are the primary species affecting humans. These organisms are mainly transmitted through tick bites but can also spread via contaminated blood transfusions, organ transplants, or during pregnancy.

Both Babesia and Bartonella are often considered co-infections with Lyme disease caused by Borrelia burgdorferi.

The child at the center of this study had facial scratches from a feral cat at age two and developed seizures two years later following an insect bite and rash. Six years after the initial cat scratch incident, NC State researchers tested blood samples—and subsequently brain biopsy samples—from the patient in 2022.

Initially, attempts to detect Bartonella and Borrelia DNA using qPCR and digital droplet PCR on blood samples yielded negative results. However, further tests on brain biopsy samples identified DNA from both Bartonella henselae and two Babesia species: B. odocoilei and B. divergens-like MO-1.

Edward Breitschwerdt, Melanie S. Steele Distinguished Professor of Internal Medicine at NC State's College of Veterinary Medicine explained: “The interesting lesson we learned from this particular case was that Bartonella DNA was not detected in the initially tested blood samples despite detection of the organisms’ DNA in the brain tissue culture samples.”

He added: “The brain is usually considered an ‘immune privileged site,’ meaning that it is difficult for an infection to cross that barrier.” The observed pathophysiological changes corresponded with areas affected by facial scratches from earlier encounters with a feral cat.

Breitschwerdt also noted: “The other unexpected piece to this puzzle is the potential effect of the Babesia infection...we need to ask ourselves going forward what we may be missing in cases like this child.”

Published in the Journal of Central Nervous System Disease on March 12, 2025, this work received support from Steven & Alexandra Cohen Foundation with contributions from Ricardo Maggi and Emily Kingston at NC State University.