Whipworm

The human whipworm (Trichuris trichiura or Trichocephalus trichiuris), is a roundworm, which causes trichuriasis when it infects a human large intestine. The name whipworm refers to the shape of the worm; they look like whips with wider "handles" at the posterior end.

Infections
Symptoms include:
 * Light infestations are frequently asymptomatic.
 * Heavy infestations may have bloody diarrhea.
 * Long-standing blood loss may lead to iron-deficiency anemia.
 * Rectal prolapse is possible in severe cases.

Infection occurs through accidental ingestion of eggs and is more common in warmer areas. 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 50 mm (2 inches) long. Neither the male nor the female has much of a visible tail past the anus.

Whipworm infestation is detectable by stool examination, which can detect eggs and charcot-leyden crystals. Mebendazole is 90% effective in the first dose, and albendazole may also be offered as an anti-parasitic agent. Adding iron to the bloodstream helps solve the iron deficiency and rectal prolapse.

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

Infection can be avoided by proper disposal of human feces, not eating dirt, and not eating crops fertilized with night soil.

Dog and cat whipworms
Whipworms develop when a dog swallows whipworm eggs, passed from an infected dog. Symptoms may include diarrhea, anemia, and dehydration. The dog whipworm (Trichuris vulpis) is commonly found in the U.S. It is hard to detect at times, because the numbers of eggs shed are low, and they are shed in waves. Centrifugation is the preferred method. There are several preventives available by prescription from a veterinarian to prevent dogs from getting whipworm.

The cat whipworm is a rare parasite. In Europe it is mostly represented by Trichuris campanula, and in North America it is Trichuris serrata more often. In Whipworm eggs found in cats in the North America must be differentiated from lungworms, and from mouse whipworm eggs just passing through.

Pig whipworms (Trichuris suis) in treating other disorders
It has been suggested that a contributing cause of intestinal disorders is immune system reaction to the patient's own body, and that adding worms for the immune system to attack instead may alleviate the symptoms. In a preliminary study, "among 100 volunteers with Crohn's disease and 100 with ulcerative colitis, both of which are diseases classified under IBD [inflammatory bowel disease], the remission rate was 70% and 50%, respectively" after ingesting eggs of the pig whipworm Trichiuris suis. See Helminthic therapy.