Guide to Parasites—Nemotoda (Roundworms)

There are five different groups of parasitic invaders:

Protozoa

Roundworms

Tapeworms

Flukes

Spirochetes

Nematoda (Roundworms) (“NEH-muh-tō-duh”)

The adult nematoda produces eggs called ova or larvae. The eggs usually become infectious in soil or in a intermediate host before humans are infected. Unless infestation is heavy, many people do not show signs of disease. Humans can host and coexist with a few worms for years.

Round worms have different known species:

Round worm (Ascaris lumricoides and Ascaris suum) are the most common intestinal parasite in the world as more than a billion people are affected. Adult worms can travel through the body and end up in the liver, heart, and lungs. It resembles the common earth worm in appearance and is spread directly to humans from soil or food contaminated with human feces.

Hookworm (Necor americanus, Ancylostoma duodenal) larvae are found in warm moist soil, and enter the body by penetrating the skin. They are found in people who frequently go barefoot. The teeth of the larvae attach to the intestinal mucosa and rob the body of large amounts of blood.

Pinworm (Enterbius vermicularis) is the most common of all worms in the United States and is most prevalent in children. Transmission occurs through contaminated food, water and house dust as well as human to human contact.

Strongyloides (Strongyloides stercoralis) is unique because the mature adult can reproduce entirely in the human host or grow into a free living worm in soil. Strongyloides produce auto infection in the host and can remain in the body for more than 30 years.

Trichinella (Trichinella spiralis) infection in various stages can be blamed for just about any symptom known to man because it can masquerade as 50 or more familiar diseases. These tiny round worms are passed on from under-cooked pork, but also are found in the muscles of walrus and bear.

Anisakine Larvae can infect humans who consume raw, pickled, or smoked herring or eat other raw or undercooked fish (sushi). Sometimes the worms have to be surgically removed.

Dog and Cat Roundworm (Toxocara canis, Toxocara cati) cause a disease called visceral larva migrans, mainly in children. Food, water, and soil contaminated with roundworm eggs are the most common sources of infection.

Filarial (Wuchereria Bancroft, Brugia malayi, Onchocerca volvulus, Loa loa, Mansonella streptocerca, Masonella perstans, Mansonella ozzardi) Including dog heartworm, there are eight species of filarial known to infect people. Transmitted by blood sucking insects and flies, the filarial are microscopic roundworms that cause diseases endemic to tropical Africa, Southeast Asia and the South Pacific.

Symptoms to look for when roundworms are involved:

This is Part 3 of your parasite education. Go back to learn if You Could Have Parasites. To learn more, continue on to learn about Protozoa, Cestoda (Tapeworms), Trematoda (Flukes) and Spirochetes. Or learn How to Treat Parasitic Infections. Download my FREE Parasites Booklet.