Invasive group A streptococcal (iGAS) disease was placed under surveillance in Alberta in August 1999. The purpose of this study was to determine the incidence rates of iGAS infections throughout Alberta over a 3-year period (2000 to 2002) and to better understand the epidemiology of iGAS in this province. There were a total of 441 cases of invasive GAS disease over the 3 years examined (average population over 3

We determined the incidence of invasive group A streptococcal (GAS) disease among children < or =14 years of age in Alberta, Canada, with a focus on infections associated with varicella. During 2000-2002, there were 71 cases of invasive GAS disease among patients in this age group. Fourteen cases occurred in children with varicella (19.7%), for an annual incidence of 0.73 varicella-associated cases per 100,000 children. Necrotizing fasciitis was not noted in patients with invasive GAS disease and varicella.