Outbreak of Group A Streptococcal Bacteremia in Sweden: An Epidemiologic and Clinical Study

Abstract

The nationwide incidence of group A streptococcal bacteremia in Sweden was 1.8 per 100,000 population in 1987. During the winter season 1988-1989, the reported cases rate doubled and then declined to the previous level. The peak was due to a type T1/M1 Streptococcus pyogenes strain associated with an increased case fatality rate (33% vs. 15% for other T types). The highest incidence rates were found in the age groups less than 12 months and greater than 70 years. Among a sample of 79 patients hospitalized in November or December 1988, a portal of entry, mainly cutaneous, was recognized in 89% of the patients and concomitant conditions in 67%. Among the clinical findings were signs of skin or soft tissue infection (41%), local or generalized pain (41%), vomiting or diarrhea (24%), cough (18%), and upper respiratory tract symptoms (12%). A fatal outcome was associated with high age, lower respiratory tract or unknown focus, leukopenia on admission, start of antibiotic therapy greater than 6 h after the patient's initial contact with a physician, and a rapid clinical course including multiple organ failure. Renewed awareness of the many facets of fulminant streptococcal infection represents one approach to minimize the case fatality rate.