A Novel Escherichia coli O157:H7 Clone Causing a Major Hemolytic Uremic Syndrome Outbreak in China

Abstract

An Escherichia coli O157:H7 outbreak in China in 1999 caused 177 deaths due to hemolytic uremic syndrome. Sixteen outbreak associated isolates were found to belong to a new clone, sequence type 96 (ST96), based on multilocus sequence typing of 15 housekeeping genes. Whole genome sequencing of an outbreak isolate, Xuzhou21, showed that the isolate is phylogenetically closely related to the Japan 1996 outbreak isolate Sakai, both of which share the most recent common ancestor with the US outbreak isolate EDL933. The levels of IL-6 and IL-8 of peripheral blood mononuclear cells induced by Xuzhou21 and Sakai were significantly higher than that induced by EDL933. Xuzhou21 also induced a significantly higher level of IL-8 than Sakai while both induced similar levels of IL-6. The expression level of Shiga toxin 2 in Xuzhou21 induced by mitomycin C was 68.6 times of that under non-inducing conditions, twice of that induced in Sakai (32.7 times) and 15 times higher than that induced in EDL933 (4.5 times). Our study shows that ST96 is a novel clone and provided significant new insights into the evolution of virulence of E. coli O157:H7.

Molecular Typing of Escherichia coli O157:H7 Isolates from Swedish Cattle and Human Cases: Population Dynamics and Virulence

“…Lineage I (LSPA-6 111111) has caused several outbreaks in Asia and the United States, including a major outbreak in 1999, which caused 177 deaths in Xuzhou, China (29). In the present study, a single LI isolate was found from a human case.…”

Rapid and Specific Detection of Escherichia coli O157:H7 in Ground Beef Using Immunomagnetic Separation Combined with Loop-Mediated Isothermal Amplification

“…A recent, multistate outbreak of Shiga toxin-producing EHEC O157:H7 infections that occurred in the US from April to June 2014 and was linked to ground beef, has caused an increased alarm on food safety. During 1999-2000, the Jiangsu, Anhui and Henan Provinces in China faced a massive outbreak of EHEC O157:H7 which caused 177 deaths due to hemolytic uremic syndrome [Xiong et al, 2012].…”

Virulence gene profiles of Shiga-toxin producing Escherichia coli isolates from retail raw meat in Iran.

“…There are several reports associated with outbreaks of STEC around the world. In a massive outbreak in China, 195 hospitalised HUS patients and 177 deaths have been reported (Wang et al, 2011;Xiong et al, 2012). In another outbreak caused by non-O157 STEC, infected cases including 43 deaths have been recently reported in the European Union (ECDC, 2011).…”