Infectious agents

How are infectious agents related to bipolar disorder?

Several markers of infectious agents have been investigated in people with mental disorders due to their neurological interactions. Any association between these agents and risk of subsequent bipolar disorder remains unclear.

Infectious agents include Toxoplasma gondii and Borna Disease Virus. Toxoplasma gondii is a parasitic protozoa usually hosted by domestic cats and other warm-blooded animals, including humans. Borna Disease Virus is the key causative component of Borna disease, a neurological syndrome primarily affecting animals, but sometimes humans.

What is the evidence for markers of infectious agents in people with bipolar disorder?

Moderate to high quality evidence suggests a small effect of increased markers for Borna disease virus and for Toxoplasma gondii in people with bipolar disorder compared to controls. Increases in Toxoplasma gondii antibodies were particularly apparent in people with bipolar disorder who were under 40 years of age. There were no differences in herpes viruses antibodies between patients and controls.

December 2021

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Last updated at: 3:01 pm, 13th April 2022
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NeuRA Libraries

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