Hookworms are small (less than 0.5 inches long) parasitic worms that can cause infections in the small intestines. The major species of hookworms associated with infections in humans are Ancylostoma duodenale and Necator americanus. They get their name from the teeth (“hooks”) or cutting plates in their mouths by which they attach themselves to the intestinal wall.
Hookworm diseases are most common in tropical and subtropical climates. These infections develop after a person has contact with soil contaminated with human feces. Children are at high risk because they often play barefoot in areas with contaminated soil. In soil, hookworm eggs hatch and form larvae, which then burrow through the skin of a person’s foot and crawl into the blood. The blood carries the larvae to the lungs, where they enter into the air sacs. The hookworms then crawl up the breathing tubes to the throat, where they are swallowed. The larvae pass through the stomach and mature into adult worms in the bowel. The worm holds onto the bowel wall with hooks, which cause minor bleeding. Adult hookworms live in the bowel and lay eggs that pass out of the child with the stool.
Signs and Symptoms
Most children with hookworm infections have no signs or symptoms. However, especially when the infection is long term, it can cause iron deficiency and anemia (low red blood cells) because of bleeding from the bowel wall where the worm is attached. Other symptoms include mild diarrhea and stomach cramps. An itchy, red skin rash (ground itch) can appear on the feet where the larvae entered the body. Lung inflammation with cough, wheezing, and fever rarely occur while the larvae migrate through the lungs. Several weeks after exposure to this hookworm, a loss of appetite and weight loss may occur. Chronic infections can lead to poor nutrition.
How Is the Diagnosis Made?
A stool sample from your child will be tested in the laboratory to look for evidence of hookworm eggs.
Antiparasitic drugs are used to treat hookworm infections. The oral medicines commonly prescribed include a single dose of albendazole or 3 days of mebendazole or pyrantel. One to 2 weeks following treatment, your pediatrician may test another stool sample from your child. The drug therapy should be repeated if the infection persists.
Iron supplements help replace the iron your child has lost.
What Is the Prognosis?
Proper treatment of hookworm infections results in a high recovery rate.
How Is the Diagnosis Made?
Reinfection is common. Wearing shoes prevents the larvae from entering the body through the feet. If your child goes barefoot, make sure she avoids contact with soil that may be contaminated with human feces.