Infection occurs through ingestion of eggs and is more common in warmer areas. Whipworms eggs are passed in the feces of infected persons, and if an infected person defecates outside or if untreated human feces as used as fertilizer, eggs are deposited on soil where they can mature into an infective stage. Ingestion of these eggs "can happen when hands or fingers that have contaminated dirt on them are put in the mouth or by consuming vegetables or fruits that have not been carefully cooked, washed or peeled." The eggs hatch in the small intestine, and then move into the wall of the small intestine and develop. On reaching adulthood, the thinner end (the front of the worm) burrows into the large intestine and the thicker end hangs into the lumen and mates with nearby worms. The females can grow to long. Neither the male nor the female has much of a visible tail past the anus.

Whipworm commonly infects patients also infected with "Giardia", "Entamoeba histolytica", "Ascaris lumbricoides", and hookworms.

Life cycle
Treatment of inflammatory disorders
Infection
Other animals