Escherichia coli O157 Infection and Hemolytic Uremic Syndrome (HUS), 2005

During 2005, 121 culture-confirmed cases of Escherichia coli O157 infection (2.4 per 100,000 population) were reported. This represents a 10% increase from the 110 cases reported in 2004 and a 33% decrease from the median number of cases reported annually from 1997 to 2004 (median, 181 cases; range, 110 to 219). Fifty-nine (49%) cases occurred in the Twin Cities metropolitan area. The remaining 62 cases occurred throughout Greater Minnesota. One hundred two (84%) cases occurred during May through October. The median age of case-patients was 15.5 years (range, 1 to 83 years). Forty-six (38%) case-patients were hospitalized; the median duration of hospitalization was 3 days (range, 1 to 33 days).

Three E. coli O157 outbreaks were identified during 2005. One of these outbreaks was foodborne, associated with consumption of prepackaged nationally distributed lettuce salad. This outbreak resulted in 23 confirmed cases in Minnesota, two confirmed cases in Wisconsin, and one confirmed case in Oregon. There were two associated cases of hemolytic uremic syndrome (HUS). There was one daycare-associated outbreak of E. coli O157, resulting in seven confirmed cases and two cases of HUS. The route of transmission was likely person-to-person. There was one waterborne outbreak of E. coli O157, at a swimming beach, resulting in four confirmed cases. There were no associated HUS cases.

In 2005, 17 HUS cases were reported. There were no fatal cases. From 1997 to 2005, the median annual number of reported HUS cases in Minnesota was 15 (range, 9 to 25), and the overall case fatality rate was 7.6%. In 2005, the median age of HUS case-patients was 6 years (range, 1 to 58 years); all cases but one occurred in children. All 17 case-patients were hospitalized, with a median hospital stay of 11 days (range, 2 to 70 days). Fifteen of the 17 HUS cases reported in 2005 were post-diarrheal. E. coli O157:H7 was cultured from the stool of nine (53%) case-patients. No non-O157 shiga toxin-producing E. coli were isolated from case-patients. E. coli O157 serology was positive in three HUS patients with a negative stool culture.

• For up to date information see:E. coli O157:H7 and HUS
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2005