Streptococcal Invasive Disease Group A, 2009

MDH has been conducting active surveillance since 1995 for invasive disease caused by group A Streptococcus (GAS), also known as Streptococcus pyogenes. Invasive GAS is defined as GAS isolated from a usual sterile site such as blood, cerebral spinal fluid, or from a wound when accompanied with necrotizing fasciitis or streptococcal toxic shock syndrome (STSS).

One hundred eighty-nine cases of invasive GAS disease (3.6 per 100,000), including 21 deaths, were reported in 2009, compared to 185 cases and 20 deaths in 2008. Ages of cases ranged from 4 days to 94 years (median, 50 years). Fifty-eight percent of the cases were residents of the metropolitan area. Fifty-nine (31%) cases had bacteremia without another focus of infection, 27 (14%) cases had cellulitis, and 18 (10%) cases had an abscess. There were 15 (8%) cases of primary pneumonia and 6 (3%) cases of necrotizing fasciitis. Fifteen (8%) cases had septic arthritis and/or osteomyelitis, and 3 (2%) had STSS. Eight (4%) cases were residents of eight different long-term care facilities.

The 21 deaths included 6 cases of bacteremia without another focus of infection, 4 cases of cellulitis, and 3 cases of pneumonia. The 8 remaining fatal cases had pneumonia and STSS (2), cellulitis and necrotizing fasciitis (1), STSS (1), necrotizing fasciitis (1), peritonitis (1), mastoiditis (1), and septic arthritis (1). The deaths occurred in persons ranging in age from 1 month to 89 years. Health histories were available for 20 cases who died and all had significant underlying medical conditions reported. The conditions most frequently reported were diabetes (6) and atherosclerotic cardiovascular disease/coronary artery disease (5).

• For up to date information see>> Group A Streptococcus (GAS)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2009