This Is Your Brain On Parasites: How Tiny Creatures Manipulate Our Behavior and Shape Society

by Kathleen McAuliffe

The Torah contains much more medical wisdom—and by that I don’t mean merely its famous admonishments to avoid eating pork (a source of trichinosis, a parasitic disease caused by a roundworm) and shellfish (filter feeders that concentrate contaminants) and to circumcise sons (bacteria can collect under the foreskin flap, so removing it is believed to have lowered the spread of STDs). Jews were instructed to bathe on the Sabbath (every Saturday); cover their wells (a good idea, as it kept out vermin and insects); engage in cleansing rituals if exposed to bodily fluids like blood, feces, pus, and semen; quarantine people with leprosy and other skin diseases and, if infection persisted in the community, burn their clothes; bury the dead quickly before corpses decomposed; submerge dishes and eating utensils in boiling water after use; never consume the flesh of an animal that had died of natural causes (a sign that it might have been felled by illness) or eat meat more than two days old (likely on the verge of turning rancid).