Sample of recent research by Edward Breitschwardt, DMV, to follow up our conversation on human mothers infecting their children. He seemed to suggest it is quite possible but better to do more research on this concern.
He did an excellent study on this precise topic in cats. Study at the end of this post below.
Schaller MD Simple Summary
Like infected humans that may be 20% of the population, health and low stressors aid in the limitation of Bartonella in those with an effective immune system. Does this protection last 20-50 years?
Article Basic Discoveries (Listed by JS)
Three Bartonella species commonly infect the domestic cat.
[And] may make it difficult for cats to become pregnant or have healthy offspring.
The transmission of Bartonella from cats to kittens does not occur in healthy cats, but free-roaming domestic cats are often chronically stressed and/or co-infected with other pathogens.
Therefore, we tested the placenta, fetus, ovary, and uterus tissue of free-roaming domestic cats to detect Bartonella DNA or culture live Bartonella.
Bartonella DNA was detected in 28% (5/18) cats.
Bartonella was not grown from any cat, but Bartonella DNA was detected in liquid culture.
Therefore, we concluded that viable Bartonella may infect the cat’s placenta….
Abstract
The domestic cat is the primary reservoir host of three flea-borne Bartonella species, one of which (Bartonella henselae) causes reduced fertility and reproductive failure in experimentally infected cats. Vertical transmission of Bartonella has been documented only in B-cell deficient mice, but not immunocompetent animals. As many free-roaming cats are chronically infected with Bartonella and may be immunocompromised by environmental stress or coinfection, we attempted to isolate Bartonella from the fetal and placental tissues of pregnant queens spayed during trap–neuter–release. Four samples from each tissue (ovary, uterus, fetus, and placenta) were split for direct DNA extraction, liquid culture, and culture on a blood agar plate. Samples from infected queens were inoculated into liquid media and sampled weekly for three weeks for DNA extraction and plating. Bartonella DNA was sequenced directly from 28% (5/18) of the free-roaming queens. For these five queens, liquid enrichment culture was attempted in duplicate for fetal and placental samples. Bartonella clarridgeiae DNA was amplified using qPCR liquid enrichment cultures from the placentas of two cats. These findings suggest that viable Bartonella organisms are present in feline reproductive tissue. Additional studies are needed to assess the transplacental transmission of Bartonella spp. and Bartonella’s influence on fetal development.
Recent Study: Moore CO, Maggi R, Ferris K, Breitschwerdt EB. Repeated Detection of Bartonella DNA in Feline Placenta: Potential Implications for Placental and Fetal Development. Animals. 2025; 15(14):2041. https://doi.org/10.3390/ani15142041
Full Article at: https://doi.org/10.3390/ani15142041
James Schaller, MD has been aggressively researching Bartonella for 23 years. He will be adding to his 12 emerging infection books by writing the definitive textbook on Human Bartonella Symptoms, Testing, and the Many Treatment Options.