Strongyloides stercoralis shows remarkable persistence in the human host, causing a disease that may be very severe or even fatal. Through hyperinfection the disease may persist for as long as 30 yrs. without reinfestation, and consequently clinical symptoms may develop many yrs. after the patient leaves an area where the disease is endemic. A case is reported which showed long persistence of the infestation with a fatal outcome. Post-mortem examn. revealed massive involvement of the lungs and intestinal tract as well as previously undescribed lesions of the heart. Although gastro-intestinal symptoms predominate the presence of the parasite in other organs may give rise to symptoms pointing toward primary disease in these areas. Gentian violet therapy is most commonly used but lack of careful follow-up examn. has given rise to a false sense of security as regards the efficacy of this drug in eradicating the infestation. Intraduo-denal instillation of the drug is worthy of trial in persistent cases, and if there is evidence of hyperinfection intraven. admn. of gentian violet should be considered.