Getting drugs into the brain is hard. Maybe a parasite can do the job

Some question if a parasite can ever be rendered harmless enough to be used as a treatment

A microscope image of a Toxoplasma gondii oocyte. The background is light green. The parasite appears as two round cells encased in an oval outer shell.

Toxoplasma gondii is a sometimes deadly brain parasite (shown here in its infectious egglike form). Some scientists want to tame it to help deliver medications to the brains of people with neurologic diseases.

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A mind-bending parasite may one day deliver drugs to the brain.