A food-borne outbreak of Shigella sonnei gastroenteritis, Austria, 2008

Abstract

We report on the first foodborne outbreak of Shigella sonnei described in Austria. On July 14 2008, AGES was informed of a cluster of 22 laboratory-confirmed cases of infection with S. sonnei restricted to public health district X in the province of Salzburg. All cases had attended a youth-group trip to a small village in the province of Tyrol from July 7 to July 9. An outbreak case among the trip participants was a person who (1) attended the trip and (2) fell ill with diarrhea in the period between July 8 and July 12. Among the 61 trip participants, 42 fitted the outbreak case definition, including 31 culture-confirmed cases. A household outbreak case was a person who (1) did not participate in the trip, (2) fell ill with diarrhea not before July 10 and (3) had household contact with an outbreak case between one and three days before onset of illness. Of the 11 household outbreak cases, 10 were tested by stool culture and four of these had a laboratory-confirmed S. sonnei infection. In addition, one of the two hostel staff tested positive for S. sonnei. All 36 isolates were biotype gl, lysotype 12, and were indistinguishable from each other by PFGE. A cohort study among the trip participants revealed a risk ratio of 2.71 for consumption of salad (on at least 1 of the 3 days of the trip) (95% CI: 1.38-5.32, P = 0.004). Among the 42cases, 34 could be explained by consumption of salad. The landlady of the hostel, who prepared the salad with bare hands, was a carrier and was assumed to be the source of contamination of the salad. Without proper epidemiological analytical investigation of this shigellosis outbreak, its association with food consumption would not have been identified.

Real-time PCR using SYBR Green for the detection of Shigella spp. in food and stool samples

“…This finding was similar to those determined in the previous studies which several outbreaks have been associated with foods consumed raw and processed or prepared by hand [32,33]. A wide range of salads have previously been involved in foodborne outbreaks of shigellosis [31,34,35].…”

A Waterborne Outbreak of Shigella sonnei with Resistance to Azithromycin and Third-Generation Cephalosporins in China in 2015

“…Because of the low infectious dose and environmental persistence, S. sonnei can be spread by water (17)(18)(19)(20), food (21,22), and direct person-to-person transmission (23,24), which can trigger sporadic cases or family outbreaks and may cause more extensive secondary transmission from a common source (25,26). Therefore, S. sonnei outbreaks in childcare centers and schools can typically spread to the community or to other cities.…”

Development of selective and differential medium for Shigella sonnei using three carbohydrates (lactose, sorbitol, and xylose) and X-Gal

“…Shigellosis is highly virulent because it is easily transmitted from person to person via the fecal-oral route (Wachsmuth and Morris, 1989). Shigellosis outbreaks are also associated with contaminated raw foods or inappropriately prepared processed foods (Cowden et al, 1995;Dunn et al, 1995;Frost et al, 1995;Gaynor et al, 2009;Hosseini and Kaffashian, 2010;Kapperud et al, 1995;Kuo et al, 2009;Lee et al, 1991;Lew et al, 1991;Terajima et al, 2004;Yagupsky et al, 1991). Various selective and differential media have been used to detect and isolate Shigella.…”