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Persons using assistive technology might not be able to fully access information in this file. For assistance, please send e-mail to: mmwrq@cdc.gov. Type 508 Accommodation and the title of the report in the subject line of e-mail. Acute Rheumatic Fever -- UtahIn early 1985, physicians at Primary Children's Medical Center in Salt Lake City noticed an apparent increase in cases of acute rheumatic fever (ARF) (1). As a result, the Utah Department of Health increased efforts to promote physician reporting of cases, and 136 cases of ARF were reported from January 1, 1985, through December 31, 1986. One hundred and seven (79%) were verified as first-attack cases by the Jones Criteria (Revised) for Guidance in the Diagnosis of Rheumatic Fever, and data were collected on 99 (93%) verified cases by telephone interview (2). An investigation of this unexpected occurrence confirmed an increase in the state's rate of rheumatic fever and defined characteristics of patients; these characteristics may help direct control efforts. The 99 verified cases were in 20 of Utah's 29 counties; the largest number occurred in the more heavily populated counties of Salt Lake and Utah. The cases occurred throughout the year, with a peak during the months of March and April. The mean age of patients was 11.8 (range = 3-42); seven patients were greater than or equal to 28 years of age. Incidence rates of ARF in children between the ages of 3 and 17 were 11.8/100,000 population in 1985 and 8.2/100,000 in 1986. Ninety-four percent of all patients were Caucasian; 4%, Pacific Islanders; 1%, Hispanic; and 1%, Asian. Fifty-seven percent were male. The mean household size was 6.1 with a mean income of $25,000-$30,000 (the poverty level for a family of six is $15,985). Fifty-six percent of the patients' parents had attended or completed college. Although 50 of the 99 patients described a sore throat during the 2-month period before onset of rheumatic fever symptoms (range = 1-30 days, mean = 5.4 days), only 9% of patients had fever, sore throat, and tender cervical adenopathy. Thirty-one persons saw a physician for an illness before the diagnosis of ARF, and 16 had throat cultures taken; streptococci were isolated from nine of these. Sixteen (53%) of 30 patients who received an antibiotic before diagnosis of ARF subsequently received a 10-day course of an antibiotic to which the organism was susceptible. Forty-two of the 99 patients were hospitalized at the time ARF was diagnosed. The distribution of major manifestations is shown in Table 1. Thirty-eight patients had a family history of rheumatic fever in a parent, sibling, aunt, uncle, or grandparent; 22 had at least one parent with a history of ARF. Further investigations are planned to identify possible risk factors, including changes in incidence, detection, and appropriate treatment of streptococcal infections; changes in the prevalence and virulence of strains of Streptococcus; and genetic predisposition to ARF. The Utah Department of Health will continue to stimulate reporting of cases by physicians; to maintain a registry for verifying cases and to collect baseline and follow-up data on all cases; to implement physician, public, patient, and school health education programs; and to recommend consultation with a physician for febrile illnesses lasting longer than 72 hours, especially in families with histories of rheumatic fever. Reported by E Asay, R Giles, LG Veasy, MD, Primary Children's Medical Center, Salt Lake City, HR Hill, MD, Univ of Utah College of Medicine, J Ware, Cardiovascular Program, CR Nichols, MPA, State Epidemiologist, Utah Dept of Health; Respiratory Diseases Br, Div of Bacterial Diseases, Center for Infectious Diseases, CDC. Editorial NoteEditorial Note: Population-based surveys and state-operated rheumatic fever surveillance systems provide the two main sources of data on the incidence of ARF in the United States. Population-based studies have documented the steadily falling rates of ARF from 1935-1980 (3-10). For example, in the 1960s, estimated overall incidence rates were between 25-30/100,000 population in both urban and suburban settings; by 1980, they were 0.2-0.8 cases/100,000 population. However, rates among all races except whites continue to be several times higher than the rate among whites. A recent survey of 50 states and the District of Columbia conducted by CDC showed that, in the past 2 to 3 years, six of 24 states with passive surveillance for ARF had reported cases representing a two-fold increase over the previous baseline. Historically, surveillance for ARF has been flawed by over- and under-reporting associated with diagnostic errors and failure to verify cases (11,12). In the last 5 years, many states have discontinued ARF surveillance because of cost and the apparently low rate of disease. The reasons for the decline in incidence of ARF during the last several decades are unknown. The decrease has been attributed to a number of factors, including improved living conditions and medical care, the introduction of antimicrobials to which the organism is uniformly sensitive, and the disappearance of specific strains of group A Streptococcus that may cause rheumatic fever in susceptible persons. Of these possible explanations, the existence of rheumatogenic strains of Streptococcus remains the most intriguing and controversial. Temporal and geographic clustering of some ARF cases suggests the presence of rheumatogenic strains. In addition, the major M protein serotypes of group A Streptococcus frequently isolated today differ from the types that caused epidemic rheumatic fever in military populations 20 years ago and from the predominant strains isolated from ARF patients in northern cities in the 1950s (13,14). The role of particular strains in Utah is unclear because of the small number of isolates of group A Streptococcus recovered from patients and family members. Thirty-eight percent of patients in Utah had a history of ARF in their extended families. Some investigators believe individuals may have a genetic susceptibility to ARF. Studies of the distribution of histocompatibility leukocyte antigens (HLA) in patients with ARF and in healthy control subjects have been inconclusive. One recent study reported a higher frequency of HLA-DR2 phenotype among black patients with rheumatic fever than among the control population, while Caucasians showed a higher frequency of HLA-DR4 phenotype (15). Further support for a link between genetic constitution and susceptibility to ARF is the finding of a B cell alloantigen, 883, in 75% of patients with rheumatic fever in New York City and Bogota, Columbia, as compared with 20% of controls (16,17). The increased incidence of ARF in Utah may represent a cyclical pattern of the disease not previously recognized. Since 50% of patients with ARF did not have a sore throat during the 2-month period before onset, more thorough throat culturing of symptomatic patients will not eliminate rheumatic fever. Further studies are needed to better define whether infection by certain strains of Streptococcus are more likely to result in ARF and what genetic factors may predispose to illness. The Respiratory Diseases Branch, Division of Bacterial Diseases, Center for Infectious Diseases, CDC, would like to be notified by state health departments of other suspected clusters of cases of ARF as well as to receive isolates of group A Streptococcus isolated from patients with known or suspected ARF through state health laboratories. References
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