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Case Study: Bartonella, Babesia Co-Infection in Family Associated with Neurological Illnesses

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For Immediate Release

Ed Breitschwerdt

In a new case study, researchers from North Carolina State University found that a family suffering from illnesses that included neurological symptoms were co-infected with both several Bartonella species and Babesia divergens-like MO-1. The study presents more evidence of these co-infections in humans and further support for stealth Babesia and Bartonella pathogens as a cause or cofactor in neurological and neuropsychiatric symptoms.

Bartonella are a group of vector-borne bacteria transmitted primarily via arthropods like fleas, lice and potentially ticks, but also by the animals that harbor them. There are at least 45 different known Bartonella species, of which 18 have been found to infect humans. The most commonly known species is Bartonella henselae, which causes cat scratch disease in humans.

Improved methods for detecting Bartonella infection in animals and humans have led to the diagnosis of bartonelloses in patients with a host of chronic illnesses, as well as in some patients with psychiatric symptoms.

Babesia is a malaria-like protozoa that infects red blood cells. In the U.S., the main Babesia species that infect humans are B. microti, B. duncani and B. divergens-like. Transmission occurs mainly by tick bite, but there are reports of transmission by transfusion of contaminated blood, organ transplantation and transplacental transmission.

Babesia and Bartonella are often suspected as co-infections with Lyme disease, caused by the bacterium Borrelia burgdorferi.

In the latest study, the sudden onset of neurological symptoms in a 10-year-old boy coupled with neurological illnesses in other family members led to an investigation into a family of five: a mother, father, two daughters and one son.

The son’s illnesses manifested in May 2021, with psychiatric diagnoses including obsessive–compulsive disorder, oppositional defiant disorder and attention deficit disorder. Subsequently, other family members developed neurological and physical symptoms. The father and oldest daughter developed fatigue, insomnia, headaches, and neurological symptoms; the mother had ocular migraines; and the younger daughter had severe menorrhagia that lasted 130 days following her first menstrual cycle.

“The family reported flea exposure,” says Edward Breitschwerdt, Melanie S. Steele Distinguished Professor of Internal Medicine at NC State’s College of Veterinary Medicine. “Fleas are known to transmit three to five different species of Bartonella. So we tested not only each family member, but also both of their dogs, one pet rabbit, and fleas.”

Breitschwerdt and the NC State team used Bartonella immunofluorescence antibody assays and digital droplet PCR testing to detect and amplify Babesia and Bartonella DNA in the blood samples. All family members and one dog were infected with B. divergens-like MO-1, both parents were infected with B. microti, and all family members, both dogs, and one pet rabbit were infected with Bartonella (B. quintana and/or B. henselae, or an undetermined species)

“The Babesia finding was especially surprising due to the species involved,” Breitschwerdt says. “B. divergens-like MO-1 has only been documented in three or four human cases in the U.S. and never reported in a dog. To find it in an entire family means that transmission may be more frequent and symptoms more complicated than we currently understand.”

“What was incredible to me is how this family clearly demonstrated why a One Heath approach to physical and neuropsychiatric illness is needed,” says Dr. Rosalie Greenberg, a child and adolescent psychiatrist in private practice and paper co-author. “A family is a complex system that includes all living members which means humans, dogs, cats, rabbits and any other creatures that share the same environment.”

“The other piece to this work is that we continue to build the case for the role of vector-transmitted organisms in illnesses, both neurological and chronic in nature,” Breitschwerdt adds. “These organisms may prove to be far more important in causing neurological illnesses than anyone dreamed.”

The work appears in Pathogens and was supported by the Steven & Alexandra Cohen Foundation. NC State researchers Ricardo Maggi, Charlotte Moore, Cynthia Robveille and Emily Kingston also contributed to the work.

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Note to editors: An abstract follows.

“A One Health Zoonotic Vector Borne Infectious Disease Family Outbreak Investigation”

DOI: 10.3390/pathogens14020110

Authors: Edward B. Breitschwerdt, Ricardo G. Maggi, Charlotte O. Moore, Cynthia Robveille, Emily Kingston, North Carolina State University; Rosalie Greenberg, Medical Arts Psychotherapy Associates
Published: Jan. 23, 2025 in Pathogens

Abstract:
This study reinforces the value of a One Health approach to infectious disease outbreak investigations. After the onset of neuropsychiatric symptoms in their son, our investigation focused on a family composed of a mother, father, two daughters, the son, two dogs, and a rabbit, all with exposures to vectors (fleas and ticks), rescued dogs, and other animals. Between 2020 and 2022, all family members experienced illnesses that included neurological symptoms. Prolonged menorrhagia (130d) in the youngest daughter ultimately resolved following antibiotic administration. One dog was diagnosed with a splenic hematoma and months later spinal histiocytic sarcoma. The father, both daughters, and one dog were seroreactive to multiple Bartonella spp. antigens, whereas the mother and son were not seroreactive. Bartonella quintana DNA was amplified from specimens obtained from all family members. Based upon DNA sequencing, infection with B. quintana was confirmed for the mother and both pet dogs. Bartonella henselae DNA was amplified and sequenced from the youngest daughter, the son, and one dog (co-infected with B. quintana), and from Ctenocephalides felis collected from their pet rabbit. All five family members and one dog were infected with Babesia divergens-like MO-1. Both parents were co-infected with Babesia microti. Droplet digital PCR supported potential infection with a Borrelia species in three family members. This study provided additional case-based evidence supporting the role of stealth Babesia, Bartonella, and Borrelia pathogens as a cause or cofactor in neurological and neuropsychiatric symptoms. We conclude that a One Health investigation approach, particularly for stealth vector borne pathogens such as Babesia, Bartonella, and Borrelia spp., will enhance clinical and epidemiological understanding of these organisms for animal and human health. During outbreak investigations it is critical to document travel and vector exposure histories, symptoms, and pathology in pets and human patients, contact with rescued, wild, or feral animals and perform diagnostic testing that includes family members, pets, and vectors.