Scientists have identified over 15,000 distinct species of roundworms. Roundworms are nematodes, or tube-shaped invertebrates that live in soil. According to the University of Maryland Medical Center, the worms can range in length from 1 millimeter to 1 meter. Several species of roundworms cause parasitic infections in humans. Over one billion people on the planet may suffer from roundworm infection at any given time, but exposure is more common in warm tropical climates. Roundworm infections can cause nutritional deficiencies, making them particularly dangerous for children. Symptoms of childhood roundworm infection vary by species.
Ascariasis
The roundworm ascaris lumbricoides is responsible for ascariasis, a parasitic infection of the intestines. The single most common parasitic infection in humans, ascariasis kills 60,000 people a year, according to the National Institute of Allergy and Infectious Diseases. Symptoms in children can include a persistent cough, shortness of breath, wheezing, abdominal pain, nausea, diarrhea, bloody vomit or stool, worms in the vomit or stool, fatigue and weight loss.
Hookworm
A hookworm infection occurs when larvae of the roundworms, Ancylostoma duodenale or Necator americanus come into contact with human skin, through contaminated soil or feces. Hookworm disease is often asymptomatic in healthy children, but it can cause diarrhea, mild abdominal pain, abdominal cramping, colic and nausea. When hookworm disease becomes overwhelming due to the number of worms present in the body, it can cause severe anemia.
Pinworm
Pinworm infection, which usually occurs in children, is the most common roundworm infection in the United States. A pinworm infection can occur when a child consumes food or drink contaminated with feces containing the roundworm, Enterobius vermicularis. Often asymptomatic, pinworm infection can cause itching of the anus or vagina and disturbed sleep.
Threadworm
Threadworm is an infection caused by the roundworm Strongyloides stercorali. Strongyloidiasis in healthy children often causes no symptoms or only mild abdominal discomfort, but it can cause weight loss, anemia and diarrhea in immunocompromised individuals.
Trichinosis
Trichinosis is an infection caused by the roundworm, Trichinella spiralis. It is most commonly associated with the consumption of pork, horse meat, bear meat and walrus meat. Since legislation was enacted in the United States to compel farmers to sterilize pig feed, U.S. trichinosis rates have dropped significantly. Initial larval infection can cause diarrhea, abdominal cramping and fatigue, but if the larvae travel from the intestines to muscle tissue they can cause muscle pain, fever, swelling in the face and eyes, ocular infections and rashes.
Whipworm
Whipworm infection occurs when a person eats food contaminated with soil containing eggs of the roundworm, Trichuris trichiura. Whipworm is generally mild, but severe infections in children can cause abdominal pain, diarrhea, weight loss, bloody stool and rectal prolapse.
