Streptococcal Invasive Disease Group A, 2011

We have been conducting active surveillance for invasive disease caused by group A Streptococcus (GAS, [also known as Streptococcus pyogenes]) since 1995. Invasive GAS is defined as GAS isolated from a usually sterile site such as blood, cerebral spinal fluid, or from a wound when accompanied with necrotizing fasciitis or streptococcal toxic shock syndrome (STSS). Two hundred thirty-one cases of invasive GAS disease (4.3 per 100,000), including 17 deaths, were reported in 2011, compared to 158 cases and 13 deaths in 2010. Ages of cases ranged from 1 to 98 years (median, 55 years). Fifty percent of cases were residents of the metropolitan area. Forty-one (18%) cases had bacteremia without another focus of infection, 73 (32%) cases had cellulitis, and 25 (11%) cases had an abscess. Of the 73 cellulitis cases (10 cases had both cellulitis and an abscess), 74% had a positive blood culture and 15% had a positive joint culture for GAS. There were 32 (14%) cases of pneumonia and 21 (9%) cases of necrotizing fasciitis (2 cases had both pneumonia and necrotizing fasciitis). Twenty-four (10%) cases had septic arthritis and/or osteomyelitis. Twelve (5%) cases were residents of 12 different long-term care facilities. The 17 deaths included 3 cases of bacteremia without another focus of infection, 3 cases of septic shock, 2 cases with cellulitis, 2 cases of pneumonia, 2 cases of urinary tract infection/urosepsis, and 1 case of septic arthritis. The remaining 4 cases had multiple syndromes including 2 cases of pneumonia and septic shock; 1 case of necrotizing fasciitis and cellulitis; and 1 case of necrotizing fasciitis, septic shock, and pneumonia. The deaths occurred in persons ranging in age from 33 years to 94 years (median, 70 years). Five fatal cases had no underlying medical conditions reported. Of the 12 cases with underlying medical conditions the most frequently reported were diabetes (6) and congestive heart failure (4).

• For up to date information see>> Group A Streptococcus (GAS)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2011