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Shiga toxin-producing Escherichia coli (STEC) O80:H2 has emerged in Europe as a cause of hemolytic uremic syndrome associated with bacteremia. STEC O80:H2 harbors the mosaic plasmid pR444_A, which combines several virulence genes, including hlyF and antimicrobial resistance genes. pR444_A is found in some extraintestinal pathogenic E. coli (ExPEC) strains. We identified and characterized 53 STEC strains with ExPEC-associated virulence genes isolated in Italy and the Netherlands during 2000-2019. The isolates belong to 2 major populations: 1 belongs to sequence type 301 and harbors diverse stx2 subtypes, the intimin variant eae-ξ, and pO157-like and pR444_A plasmids; 1 consists of strains belonging to various sequence types, some of which lack the pO157 plasmid, the locus of enterocyte effacement, and the antimicrobial resistance-encoding region. Our results showed that STEC strains harboring ExPEC-associated virulence genes can include multiple serotypes and that the pR444_A plasmid can be acquired and mobilized by STEC strains. [ABSTRACT FROM AUTHOR]

Simple Summary: Hepatitis E is now recognized as an emerging zoonotic disease in Europe caused by an RNA virus (HEV) and foodborne is the main route of transmission. Human cases have been linked to the consumption of contaminated pig liver sausages, raw venison, or undercooked wild boar meat. The zoonotic genotype HEV-3 is widespread in pigs at farm level but little information is available on the occurrence of HEV-positive pigs at the slaughterhouse. The aim of this study was to investigate the prevalence of HEV-positive pigs during slaughtering, to understand which biological samples (feces and organs) were more frequently HEV positive. Our results showed that pigs positive for HEV can be slaughtered and that the percentage of positive animals depends on the age of animals. The other main result is the presence of the virus in the plasma of animals, which may contribute to the contamination of meat (muscle). Nevertheless, muscles are rarely contaminated by HEV-RNA compared to liver, which is the organ of replication. In Europe, foodborne transmission has been clearly associated to sporadic cases and small clusters of hepatitis E in humans linked to the consumption of contaminated pig liver sausages, raw venison, or undercooked wild boar meat. In Europe, zoonotic HEV-genotype 3 strains are widespread in pig farms but little information is available on the prevalence of HEV positive pigs at slaughterhouse. In the present study, the prevalence of HEV-RNA positive pigs was assessed on 585 animals from 4 abattoirs located across Italy. Twenty-one pigs (3.6%) tested positive for HEV in either feces or liver by real-time RT-PCR. In these 21 pigs, eight diaphragm muscles resulted positive for HEV-RNA. Among animals collected in one abattoir, 4 out of 91 plasma tested positive for HEV-RNA. ELISA tests for the detection of total antibodies against HEV showed a high seroprevalence (76.8%), confirming the frequent exposure of pigs to the virus. The phylogenetic analyses conducted on sequences of both ORF1 and ORF2 fragments, shows the circulation of HEV-3c and of a novel unclassified subtype. This study provides information on HEV occurrence in pigs at the slaughterhouse, confirming that muscles are rarely contaminated by HEV-RNA compared to liver, which is the most frequently positive for HEV. [ABSTRACT FROM AUTHOR]

Background: Foodborne Hepatitis A Virus (HAV) outbreaks are being recognized as an emerging public health problem in industrialized countries. In 2013 three foodborne HAV outbreaks occurred in Europe and one in USA. During the largest of the three European outbreaks, most cases occurred in Italy (>1,200 cases as of March 31, 2014). A national Task Force was established at the beginning of the outbreak by the Ministry of Health. Mixed frozen berries were early demonstrated to be the source of infection by the identity of viral sequences in patients and in food. In the present study the molecular characterization of HAV isolates from 355 Italian cases is reported., Methods: Molecular characterization was carried out by PCR/sequencing (VP1/2A region), comparison with reference strains and phylogenetic analysis., Results: A unique strain was responsible for most characterized cases (235/355, 66.1%). Molecular data had a key role in tracing this outbreak, allowing 110 out of the 235 outbreak cases (46.8%) to be recognized in absence of any other link. The data also showed background circulation of further unrelated strains, both autochthonous and travel related, whose sequence comparison highlighted minor outbreaks and small clusters, most of them unrecognized on the basis of epidemiological data. Phylogenetic analysis showed most isolates from travel related cases clustering with reference strains originating from the same geographical area of travel., Conclusions: In conclusion, the study documents, in a real outbreak context, the crucial role of molecular analysis in investigating an old but re-emerging pathogen. Improving the molecular knowledge of HAV strains, both autochthonous and circulating in countries from which potentially contaminated foods are imported, will become increasingly important to control outbreaks by supporting trace back activities, aiming to identify the geographical source(s) of contaminated food, as well as public health interventions.

Shiga toxin-producing Escherichia coli (STEC) strains are the only pathogenic group of E. coli that has a definite zoonotic origin, with ruminants and, in particular, cattle being recognized as the major reservoir. Most human STEC infections are food borne, but the routes of transmission include direct contact with animals and a variety of environment-related exposures. Therefore, STEC public health microbiology spans the fields of medical, veterinary, food, water, and environmental microbiology, requiring a "One Health" perspective and laboratory scientists with the ability to work effectively across disciplines. Public health microbiology laboratories play a central role in the surveillance of STEC infections, as well as in the preparedness for responding to outbreaks and in providing scientific evidence for the implementation of prevention and control measures. This article reviews (i) how the integration of surveillance of STEC infections and monitoring of these pathogens in animal reservoirs and potential food vehicles may contribute to their control; (ii) the role of reference laboratories, in both the public health and veterinary and food sectors; and (iii) the public health perspectives, including those related to regulatory issues in both the European Union and the United States.

Multidisciplinary collaboration has been recognised necessary for centuries and has a long tradition. It is supported by solid bases, and is required to control a number of risk factors. Its practice encounters difficulties in various critical points. At present, the models of collaboration provided by the activities of the WHO/Mediterranean Zoonoses Control Centre and by the Med-Vet-Net network of the European Community represent relevant examples.

Foodborne infections are an important Public Health concern worldwide. Most of the pathogens that play a role in foodborne diseases have a zoonotic origin. The epidemiology of foodborne infections as well as the food production and distribution chains, have remarkably changed during the past ten years. Understanding of how pathogens arrive, persist in animal reservoir or enter the food chain is a crucial step in prevention strategies. These need to be aimed to measure the overall impact of the infections,to identify trends in incidence and to recognise rapidly outbreaks also at transnational level. Enter-Net is an example of an international laboratory based surveillance network which contribute largely to European foodborne zoonosis surveillance.