We designed a multi-hospital prospective study of children less than 12 years to determine the comparative clinical profile, severity of carditis, and outcome on follow up of patients suffering an initial and recurrent episodes of acute rheumatic fever. The study extended over a period of 3 years, with diagnosis based on the Jones criteria. We included 161 children in the study, 57 having only one episode and 104 with recurrent episodes. Those seen in the first episode were differentiated from those with recurrent episodes on the basis of the history. The severity of carditis was graded by clinical and echocardiographic means. In those suffering their first episode, carditis was significantly less frequent (61.4%) compared to those having recurrent episodes (96.2%). Arthritis was more marked in the first episode (61.4%) compared to recurrent episodes (36.5%). Chorea was also significantly higher in the first episode (15.8%) compared to recurrent episodes (3.8%). Sub-cutaneous nodules were more-or-less the same in those suffering the first (7%) as opposed to recurrent episodes (5.8%), but Erythema marginatum was more marked during the first episode (3.5%), being rare in recurrent episodes at 0.9%. Fever was recorded in approximately the same numbers in first (45.6%) and recurrent episodes (48.1%). Arthralgia, in contrast, was less frequent in first (21.1%) compared to recurrent episodes (32.7%). A history of sore throat was significantly increased amongst those suffering the first episode (54.4%) compared to recurrent episodes (21.2%). When we compared the severity of carditis in the first versus recurrent episodes, at the start of study mild carditis was found in 29.8% versus 10.6%, moderate carditis in 26.3% versus 53.8%, and severe carditis in 5.3% versus 31.8% of cases, respectively. At the end of study, 30.3% of patients suffering their first episode were completely cured of carditis, and all others showed significant improvement compared to those with recurrent episodes, where only 6.8% were cured, little improvement or deterioration being noted in the remainder of the patients. We conclude that the clinical profile of acute rheumatic fever, especially that of carditis, is milder in those suffering their first attack compared to those with recurrent episodes.