While recurrence of rheumatic fever is common, recurrence after valve replacement has not been reported. A 15-year-old Ethiopian boy returned from America after mitral valve replacement in May 1986. He did not take antibiotic prophylaxis and, in February 1987, had recurrent rheumatic fever. The literature on recurrence of rheumatic fever and prophylaxis is reviewed. Monthly injections of benzathine penicillin have been shown to be the most effective drug to prevent rheumatic fever recurrences. It is recommended that patients with rheumatic heart disease in the developing world should take prophylaxis for life.