Ascaris lumbricoides is a parasitic roundworm that can live in the intestines of humans and animals. It is one of the most common parasites in the world. The adult worms are typically 3 to 8 cm long and can be seen in the stool of an infected person. The female worms produce up to 200,000 eggs daily, which are passed in the stool and can contaminate soil and water. The eggs can survive for months in the environment.
People become infected by ingesting the eggs from contaminated soil or water. Once inside the body, the eggs hatch and the larvae travel to the lungs, where they can cause a dry cough, chest pain, and difficulty breathing. The larvae then travel to the throat, where they are swallowed and move to the intestine, where they mature into adult worms.
Symptoms of an Ascaris lumbricoides infection may include abdominal pain, nausea, vomiting, diarrhea, and weight loss. In some cases, the infection may cause a blockage of the intestine, which can be life-threatening. Treatment usually involves taking medication to kill the worms.
Prevention of Ascaris lumbricoides infection includes washing hands thoroughly with soap and water after using the bathroom or changing diapers, and boiling or filtering drinking water.