Do infectious diseases cause depression?
A variety of infections have been associated with depression and other psychiatric disorders.
The first microbe to focus our attention in this area was "Treponema pallidum"-the spirochete that causes syphilis. Today, the spirochete that is most likely to be a cause of depression is "Borrelia burgdorferi," the agent of Lyme disease.
Patients with Lyme disease, for example, may become atypically irritable, agitated, or tearful at the least provocation. In addition, they may experience mood swings that may be misdiagnosed as a bipolar disorder. Viruses, such as HIV & Herpes Simplex, are also well recognized as agents of unusual neuropsychiatric and depressive states.
In these cases, identification and treatment of the underlying infectious cause is clearly critical to improving the patient's neuropsychiatric disorder.