Digestive Worms in Humans

Humans are susceptible to many parasitic worms, which generally infest the intestinal tract but can spread and thrive elsewhere in the body. While some are serious and even fatal if left untreated, others have much milder symptoms.

Types

• The vast majority of worms that infect humans are of the phylum Nematoda. They have a two-way digestive tract and exhibit cephalization, meaning their sensory and neural organs are concentrated in an anterior head. Many, though not all, are parasitic. Tapeworms are of the phylum Cestoda.

Tapeworms

• Existing in two major species, the beef or pork tapeworm, these parasites can grow up to 40 feet long. Symptoms are generally mild to nonexistent, but worms can block the intestinal tract or openings, which can cause discomfort and even fatality in extreme cases. They are acquired by eating undercooked meat.

Nematoda

• Including the trichina worm, hookworm, pinworm and whipworm, this is the largest group of parasitic worms in humans.

Hookworms

• Hookworms live in the soil and penetrate unprotected human flesh, especially feet. They can cause a local rash as well as abdominal pain and diarrhea. These half-inch worms can cause intestinal hemorrhaging if left untreated.

Pinworms

• The most common type of worm infection in America, according to eMedicineHealth.com, pinworms generally infect children and can cause irritation of the anus and vagina. While not particularly dangerous, they can be extremely irritating.

Whipworms

• Generally contracted from eating infected dried goods, whipworms burrow into the lining of the intestine, causing bloody stool and eventually vitamin A deficiencies.