Nematode Helminths of the Small Intestine

Nematode helminthic infections are most common in areas with an unhealthy water supply, inadequate sanitation, and overcrowding. Infection rates are highest in children and among immunocompromized individuals. Infection is mainly caused by the consumption of foods and drinks contaminated with the infective stages. Also, infection is transmitted by eating raw or undercooked meat infected with parasitic stages, flies, food handlers, and autoinfection. Nematode helminths infecting the small intestine could result in diarrhea and/or malabsorption, abdominal colic, discomfort, nausea, vomiting and/or constipation, together with anemia, malnutrition, and indigestion. Migrating nematode larvae in the human body results in parasitic pneumonia with severe lung complications. The following are the commonest nematode parasites infecting the small intestine: