Duration of fecal shedding of Shiga toxin-producing Escherichia coli O104:H4 in patients infected during the 2011 outbreak in Germany: a multicenter study.

ABSTRACT

BACKGROUND: In May-July 2011, Germany experienced a large food-borne outbreak of Shiga toxin 2-producing Escherichia coli (STEC O104H4) with 3842 cases, including 855 cases with hemolytic uremic syndrome (HUS) and 53 deaths. METHODS: A multicenter study was initiated in 5 university hospitals to determine pathogen shedding duration. Diagnostics comprised culture on selective media, toxin enzyme-linked immunosorbent assay, and polymerase chain reaction. Results were correlated with clinical and epidemiologic findings. Testing for pathogen excretion was continued after discharge of the patient. RESULTS: A total of 321 patients (104 male, 217 female) were included (median age, 40 years [range, 1-89 days]). Median delay from onset of symptoms to hospitalization was 4 days (range, 0-17 days). Two hundred nine patients presented with HUS. The estimate for the median duration of shedding was 17-18 days. Some patients remained STEC O104H4 positive until the end of the observation time (maximum observed shedding duration 157 days). There was no significant influence of sex on shedding duration. Patients presenting with HUS had a significantly shortened shedding duration (median, 13-14 days) compared to non-HUS patients (median, 33-34 days). Antimicrobial treatment was also significantly associated with reduced shedding duration. Children (age≤15 years) had longer shedding durations than adults (median, 35-41 vs 14-15 days). CONCLUSIONS: STEC O104H4 is usually eliminated from the human gut after 1 month, but may sometimes be excreted for several months. Proper follow-up of infected patients is important to avoid further pathogen spread.