An infection that is caused by nematodes of the genus Strongyloides, most commonly Strongyloides stercoralis, which is a soil-transmitted helminth, and which is characterized by a variety of gastrointestinal, dermatologic, and, occasionally, pulmonary manifestations. The worm's autoinfective life cycle can lead to hyper-infection and life-threatening dissemination in immunocompromised hosts decades after initial infection.