THE CONTINUING OUTBREAK OF ACUTE RHEUMATIC FEVER IN THE INTERMOUNTAIN WEST

Abstract

The incidence of acute rheumatic fever (ARF) has shown a steady decline in the United States. Attack rates in most recent studies have averaged 0.5 per 100,000 population leading to the concept that the disease has “virtually disappeared from the U.S.” Over the past 23 month period, a total of 98 cases of ARF occurred in the Intermountain West surrounding Salt Lake City, Utah. This represents an eight fold increase in the annual incidence of the disease over the past decade. The patients presented with classic signs of ARF including carditis (90%.), polyarthritis (57%), and chorea (31%). Doppler echocardiography proved to be a valuable adjunct in the diagnosis of cardiac involvement in ARF, especially in patients with chorea. The attack rate among 5 to 17 year old individuals in Salt Lake County was 18.1 per 100,000 in 1985. Only one third of the patients surveyed gave a history of a preceding respiratory infection. Culture surveys in two Utah communities where index cases occurred failed to reveal an increased prevalence of group A streptococcal carriage (15%). Examination of group A organisms from these surveys and from patients and their siblings revealed mucoid M-type 18 and M-type 3 strains. These findings indicate that acute rheumatic fever is still a health problem in the U.S. and suggest that continued attention be directed towards the recognition and appropriate therapy of acute streptococcal infections.