Research Publications (Food Safety)

During 2015–2016, we evaluated the performance of whole-genome sequencing (WGS) as a routine typing tool. Its added value for microbiological and epidemiologic surveillance of listeriosis was compared with that for pulsed-field gel electrophoresis (PFGE), the current standard method. A total of 2,743 Listeria monocytogenes isolates collected as part of routine surveillance were characterized in parallel by PFGE and core genome multilocus sequence typing (cgMLST) extracted from WGS.

Analysis of complete capsid sequences of the emerging norovirus GII.17 Kawasaki 308 from 13 countries demonstrated that they originated from a single haplotype since the initial emergence in China in late 2014. Global spread of a sublineage SL2 was identified. A new sublineage SL3 emerged in China in 2016.

In May 2016, an outbreak of Shiga toxin–producing Escherichia coli O157 infections occurred among children who had played in a stream flowing through a park. Analysis of E. coli isolates from the patients, stream water, and deer and coyote scat showed that feces from deer were the most likely source of contamination.

In Taiwan, acute gastroenteritis outbreaks caused by a new norovirus genotype GII.2 increased sharply toward the end of 2016. Unlike previous outbreaks, which often involved restaurants, GII.2 outbreaks mainly occurred in schools. Phylogenetic analysis indicates that these noroviruses are recombinant GII.P16-GII.2 strains.

In winter 2015–16, norovirus GII.17 Kawasaki 2014 emerged as a cause of sporadic gastroenteritis in children in Italy. Median patient age was higher for those with GII.17 than GII.4 infection (55 vs. 24 months), suggesting limited cross-protection for older children.

M. Suárez-Esquivel et al.

S. J. Bloomfield et al.

An unusual prevalence of recombinant GII.2 noroviruses (GII.P16-GII.2) in Guangdong, China, at the end of 2016 caused a sharp increase in outbreaks of acute gastroenteritis. This event was another non-GII.4 epidemic that emerged after the GII.17 viruses in 2014 and 2015 and warrants global surveillance.

During October–December 2016, the number of norovirus outbreaks in China increased sharply from the same period during the previous 4 years. We identified a recombinant norovirus strain, GII.P16-GII.2, as the cause of 44 (79%) of the 56 outbreaks, signaling that this strain could replace the predominant GII.4 viruses.

Although transmission of hepatitis A virus (HAV) through blood transfusion has been documented, transmission through organ transplantation has not been reported. In August 2015, state health officials in Texas, USA, were notified of 2 home health nurses with HAV infection whose only common exposure was a child who had undergone multi–visceral organ transplantation 9 months earlier.

J. Kwon et al.

To determine oral transmissibility of the L-type bovine spongiform encephalopathy (BSE) prion, we orally inoculated 16 calves with brain homogenates of the agent. Only 1 animal, given a high dose, showed signs and died at 88 months. These results suggest low risk for oral transmission of the L-BSE agent among cattle.

L. Yi et al.

K. Murray et al.

Y. Liao et al.

J. Yu et al.

We compared the epidemiology of hepatitis A and hepatitis E cases in China from 1990–2014 to better inform policy and prevention efforts. The incidence of hepatitis A cases declined dramatically, while hepatitis E incidence increased. During 2004–2014, hepatitis E mortality rates surpassed those of hepatitis A.

Z. He et al.

A norovirus was detected in harbor porpoises, a previously unknown host for norovirus. This norovirus had low similarity to any known norovirus. Viral RNA was detected primarily in intestinal tissue, and specific serum antibodies were detected in 8 (24%) of 34 harbor porpoises from the North Sea.

R. Pouillot et al.

We assessed Coxiella burnetii prevalence and genotypes in pigs in South Korea during 2014–2015. Prevalence was low among 1,030 samples tested by ELISA and immunofluorescent assay and 1,124 samples tested by PCR. Despite this finding, possible transmission of C. burnetii from pigs to humans cannot be excluded.

D. Polo et al.

To the Editor: Hepatitis E, caused by hepatitis E virus (HEV), is recognized as a zoonosis (1). HEV has been identified in a wide range of animals, and swine is the primary reservoir (2). In cattle, HEV strains have been recently described in yak (3), Holstein cows and their milk (4), and dairy cows in Xinjiang Province, China (5), but not in other cattle.

To the Editor: Norovirus is the world’s leading cause of nonbacterial acute gastroenteritis (1). Since their emergence, GII.P17-GII.17 noroviruses have replaced the GII.4 Sydney 2012 variant as the dominating norovirus genotype in parts of Asia (2), although they have been detected only sporadically, in a limited number, on other continents (3).

In England in 2015, Shigella sonnei isolates from men who have sex with men produced extended-spectrum β-lactamases and exhibited macrolide resistance. Whole-genome sequencing showed a close relationship among the isolates, which harbored a plasmid that was previously identified in a shigellosis outbreak among this population but has acquired a mobile element.