PETER FROST: Brainwashed by a microbe?

Have some microbes evolved to manipulate our brains? Perhaps, but it would be hard to prove. For one thing, we’re continually being infected by seemingly benign microbes that trigger no symptoms of infection, i.e., fever, pus formation, immune response, etc. They go about their business without our knowing they’re inside us.

For another thing, a microbe can permanently alter our mental wiring and then be removed from our body. The culprit vanishes from the scene of the crime and leaves only a few ambiguous clues. This is the conclusion of a recent study on Toxoplasma gondii. . . .

T. gondii is being studied for possible behavioral effects mainly because it has attracted so much attention. But we’re probably being manipulated by other parasites. . . .

Where to look? Cherchez la femme. Sexually transmitted diseases have much to gain from altering host behavior. I would especially look at bacterial vaginosis, chlamydia, and vaginal yeast.