Ascariasis is a parasitic infection caused by the roundworm Ascaris lumbricoides. It is one of the most common parasitic infections in humans, affecting an estimated 1.5 billion people worldwide. Ascariasis is most commonly found in tropical and subtropical regions, where sanitation is poor and people are in close contact with soil contaminated with human feces.
Ascaris lumbricoides is a large roundworm that can grow to be up to 35 centimeters in length. The adult worms live in the small intestine of the human host, where they feed on partially digested food. The eggs of Ascaris lumbricoides are passed in the feces of infected people. When the eggs are ingested by another person, they hatch into larvae that migrate through the body, eventually reaching the lungs. The larvae then travel up the trachea and are swallowed, eventually reaching the small intestine where they mature into adult worms.
