Shigellosis, 2011

During 2011, 87 culture-confirmed cases of Shigella infection (1.6 per 100,000 population) were reported. This represents a 32% increase from the 66 cases reported in 2010, but a 46% decrease from the median number of cases reported annually from 2001 to 2010 (median, 162.5; range, 66 to 493). S. sonnei accounted for 73 (84%) cases, S. fl exneri for 11 (13%), and S. boydii for 3 (3%). Cases ranged in age from 1 to 72 years (median, 36 years). Forty-three percent of cases were males 18 to 55 years of age. Ten percent of cases were ≤5 years of age. Nineteen (22%) cases were hospitalized. Of the 75 cases for which travel information was available, 17 (23%) travelled internationally (12 of 65 [19%] S. sonnei, 4 of 9 [44%] S. fl exneri, and 1 of 1 S. boydii). Eighty-seven percent of cases resided in the metropolitan area, including 48% in Hennepin County and 22% in Ramsey County. No outbreaks of shigellosis were identified in 2011.

Every tenth Shigella isolate received at MDH is tested for antimicrobial resistance. Nine isolates were tested in 2011; 89% (8 isolates) were resistant to trimethoprim-sulfamethoxazole (Sxt) and 11% (1 isolate) were resistant to ampicillin. The ampicillin-resistant isolate (S. Sonnei) was also resistant to Sxt, tetracycline (T), streptomycin (S), sulfasoxizole (Su), and cephalothin. Five other isolates with Sxt resistance had resistance phenotype SSuTSxt. All isolates tested were S. Sonnei except 1 SSuTSxt isolate that was S. Boydii.

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