New research is the latest to find evidence of a link between mental illness and infections caused by a group of bacteria commonly found in cats and other animals. The small study found that people with diagnosed schizophrenia and schizoaffective disorder were more likely to carry Bartonella bacteria in their bloodstream than a control group of patients. However, more research is needed to definitively show whether these infections can indeed contribute to mental illness.
Acute infections involving Bartonella bacteria can be particularly serious for people in poor health or with a weakened immune system. In most people, they are thought to cause only mild, short-lived illness. For years, however, Ed Breitschwerdt and his fellow researchers at North Carolina State University have speculated that the health effects of these infections may be more profound in at least some unlucky people.
Their previous work has Highlighted the case of a 14-year-old boy who suddenly developed symptoms resembling schizophrenia and was later found to be a carrier of a species of Bartonella known to cause cat scratch fever. In this case, the boy’s serious psychiatric problems seemed to go away once his chronic Bartonella infection was treated with antibiotics. Last year they published research has found that other people with similar neuropsychiatric symptoms often carry these bacteria, along with physical symptoms of an ongoing infection that appear around the same time, as separate skin lesions.
For this new research, researchers at NC State worked with researchers at the University of North Carolina. Their study, published last week in Vector-borne and Zoonotic Diseases, compared 17 people with diagnosed schizophrenia or schizo affective to a control group of 13 healthy people, in what is called a case-control study.
According to the study, both groups were the subject of extensive scrutiny. This included the use of more sensitive PCR tests, which look for the presence of DNA of pathogens in our bodies. Bartonella is a bit strange among bacteria because they are able to infect and then hide inside cells in our body (red blood cells, in the case of Bartonella). This disappearance trick allows them to survive undetected by the immune system, and it also worsens conventional tests to detect active infection. Last year, Breitschwerdt and his colleagues published research showing that this new testing technique, called digital droplet testing or ddPCR, may be more accurate at identifying Bartonella than older tests.
In 11 of the 17 people with schizophrenia or schizoaffective disorder, traces of Bartonella DNA could be found, while this was only true for one of the 13 control patients. Although cats, dogs, and even the fleas they carry can be vectors of Bartonella transmission, the team found no link between a higher risk of infection and owning a pet or pet. exposure to fleas.
The team is careful to describe their work as a pilot study, intended only to prove that further investigation into this link is worthwhile. But coupled with their previous research, Breitschwerdt believes the arguments for this theory only grow stronger.
“Our research to date continues to support a role for Bartonella species as a cause or co-factor of neuropsychiatric disease, ”Breitschwerdt told Gizmodo in an email.
However, he added, “There is a lot of work to be done to clarify these preliminary results.”
The team is already working on validating ddPCR tests for other groups of bacteria that can invade the bloodstream and may be more difficult to find with standard tests. With more funding and cooperation with other research centers, they also hope to conduct a larger study comparing people with and without schizophrenia.