Shigellosis, 2007

During 2007, 238 culture-confirmed cases of Shigella infection (5.0 per 100,000 population) were reported (Figure 2). This represents an 8% decrease from the 259 cases reported in 2006, and a 7% increase from the median number of cases reported annually from 1999 to 2006 (median, 222 cases; range, 68 to 904).

In 2007, S. sonnei accounted for 208 (88%) cases, S. flexneri for 27 (11%), and S. dysenteria for one (<1%). Case-patients ranged in age from 1 month to 90 years (median, 9 years). Fifty-one percent of case-patients were less than 10 years of age; children less than 5 years of age accounted for 28% of cases. Forty-three (18%) case-patients were hospitalized. Seventy-nine percent of case-patients resided in the metropolitan area, including 35% in Hennepin County and 14% in Ramsey County.

Five outbreaks of shigellosis were identified in 2007; all five were caused by S. sonnei. These outbreaks resulted in 17 culture-confirmed cases (representing 7% of reported Shigella cases). Four person–to-person outbreaks occurred in child daycare facilities and one community associated person-to-person outbreak also occurred.

Every tenth Shigella isolate received at MDH is tested for antimicrobial resistance. Twenty-four isolates were tested in 2007; 71% were resistant to ampicillin, 21% were resistant to trimethoprim-sulfamethoxazole, and 13% were resistant to both ampicillin and trimethoprim-sulfamethoxazole. All isolates tested were susceptible to ceftriaxone.

• For up to date information see>> Shigellosis (Shigella)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2007