Gastrointestinal involvement in STEC-associated hemolytic uremic syndrome: 10 years in a pediatric center.

BACKGROUND: The gastrointestinal (GI) tract represents one of the main targets of typical hemolytic uremic syndrome (HUS) in children. In this observational study, we tried to establish (1) the main features of GI complications during STEC-HUS and (2) the relationship between Escherichia coli serotypes and Shiga toxin (Stx) variants with hepatopancreatic involvement. METHODS: A total of 79 STEC-HUS patients were admitted to our pediatric nephrology department between January 2012 and June 2021. Evidence of intestinal, hepatobiliary, and pancreatic involvements was reported for each patient, alongside demographic, clinical, and laboratory features. Frequency of gastrointestinal complications across groups of patients infected by specific E. coli serotypes and Stx gene variants was evaluated. RESULTS: Six patients developed a bowel complication: two developed rectal prolapse, and four developed bowel perforation which resulted in death for three of them and in bowel stenosis in one patient. Acute pancreatitis was diagnosed in 13 patients. An isolated increase in pancreatic enzymes and/or liver transaminases was observed in 41 and 15 patients, respectively. Biliary sludge was detected in three, cholelithiasis in one. Forty-seven patients developed direct hyperbilirubinemia. Neither E. coli serotypes nor Shiga toxin variants correlated with hepatic or pancreatic involvement. CONCLUSIONS: During STEC-HUS, GI complications are common, ranging from self-limited elevation of laboratory markers to bowel perforation, a severe complication with a relevant impact on morbidity and mortality. Hepatopancreatic involvement is frequent, but usually short-lasting and self-limiting.

Catering of high-risk foods and potential of stored food menu data for timely outbreak investigations in healthcare facilities, Italy and Germany.

Healthcare-associated foodborne outbreaks (HA-FBOs) can cause significant morbidity and mortality, affecting particularly vulnerable hospital populations. Electronic records of food served in healthcare facilities (HCFs) could be useful for timely investigations of HA-FBOs. We explored the availability and usability of electronic food menu data to support investigations of HA-FBOs through a survey among 35 HCFs in Germany (n = 13) and in Italy (n = 22). Large variability was reported in the storage time of menu data (from no storage up to 10 years) and their formats, including paper, electronic (PDF, Word, Excel), or fully searchable databases (15/22 in Italian HCFs, 3/13 in German HCFs). Food products that may present a risk to vulnerable persons - including deli salads, raw/fermented sausage products, soft cheese, smoked fish or frozen berries - were offered on the menu of all HCFs in Germany, and one-third of the Italian HCFs. The usability of electronic food menu data for the prevention or investigation of HA-FBOs may be suboptimal in a large number of HCFs in Germany, as well as in some HCFs in Italy. Standardised collection for use of electronic food menu data might help discover the association between illnesses and food eaten during outbreak investigations. Hospital hygienists, food safety and public health authorities should collaborate to increase implementation of food safety guidelines.

Genomic Characterization of hlyF-positive Shiga Toxin-Producing Escherichia coli, Italy and the Netherlands, 2000-2019.

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.

Correction to: Case-management protocol for bloody diarrhea as a model to reduce the clinical impact of Shiga toxin-producing Escherichia coli infections. Experience from Southern Italy.

In the originally published article, the name of the 8th author Michele Quarto was inadvertently omitted during typesetting. Author's name is now correctly captured above. Also, the collaborators of the institutional group "Bloody Diarrhea Apulia Working Group" are also given here.

Case-management protocol for bloody diarrhea as a model to reduce the clinical impact of Shiga toxin-producing Escherichia coli infections. Experience from Southern Italy.

To describe an operating protocol for bloody diarrhea (BD) in a pediatric population as a rapid response to a public health threat represented by an excess of pediatric HUS cases in the Apulia region (Southern Italy) starting from 2013. The protocol was set up with the goal of correct clinical management of Shiga toxin-producing Escherichia coli (STEC) infections, reductions in subsequent cases of hemolytic uremic syndrome (HUS), and improved short- and long-term disease outcomes. The protocol consisted of rapid hospitalization of children with bloody diarrhea (BD), hematochemical laboratory tests every 12-24 hours, and prompt laboratory diagnosis of STEC. No antibiotics were recommended until diagnosis. Children positive for STEC infections underwent early vigorous volume expansion. In June-December 2018, 438 children with BD were hospitalized, of which 53 (12.1%) had a STEC infection. The most common serogroups were O26 (36.1%), O111 (23.0%), and O157 (14.8%). Thirty-one samples carried the stx2 gene. Four cases evolved into HUS (7.5%), all with favorable outcome despite neurological involvement in two cases. Prompt and accurate laboratory diagnosis of STEC infections is of the utmost importance in patients with BD for correct clinical management. The strict adherence to the protocol could reduce the progression rate of STEC infections to HUS and prevents complications. Enhanced BD surveillance may help reduce cases of pediatric HUS in Southern Italy.

A pediatric neurologic assessment score may drive the eculizumab-based treatment of Escherichia coli-related hemolytic uremic syndrome with neurological involvement.

BACKGROUND: Thrombotic microangiopathy (TMA) is a clinical syndrome encompassing a large group of rare but severe disorders including thrombotic thrombocytopenic purpura (TTP) and both typical and atypical forms of hemolytic uremic syndrome (HUS). The key role of the complement system is well known in TTP and atypical HUS, but recent reports describe its involvement in the pathogenesis of HUS secondary to gastrointestinal infections due to Shiga toxin-producing Escherichia coli (STEC). METHODS: TMA mainly affects the kidney, but extra-renal complications are frequently described. The involvement of the central nervous system (CNS) represents often a life-threatening condition and it can result in serious long-term disability in HUS patients who overcome the acute phase of illness. In the present study, we retrospectively analyzed a pediatric cohort of a single tertiary pediatric hospital in Southern Italy, in which this complication occurred in 12/54 children (22% of cases), of whom five with severe neurological involvement had been successfully treated with eculizumab. RESULTS: The great clinical variability of brain injury in our cohort has led us to retrospectively build a "neurological score" useful to assess the clinical severity of neurologic involvement. Subjects with higher neurologic score due to the most severe CNS involvement resulted in the group of patients early treated with eculizumab, obtaining a good clinical response (four out five patients). In conclusion, the early treatment with eculizumab in children with severe neurological involvement during STEC-HUS was associated with complete regression of both acute kidney injury (AKI) and neurological lesions observed at magnetic resonance imaging (MRI). CONCLUSIONS: A "neurological score" may be a useful tool to drive the early treatment of CNS complications in STEC-HUS with eculizumab, although future perspective controlled studies are urgently needed to validate this therapeutic approach.

Group A rotavirus surveillance before vaccine introduction in Italy, September 2014 to August 2017.

IntroductionGroup A rotaviruses (RVA) are the leading cause of acute gastroenteritis (AGE) in young children, causing ca 250,000 deaths worldwide, mainly in low-income countries. Two proteins, VP7 (glycoprotein, G genotype) and VP4 (protease-sensitive protein, P genotype), are the basis for the binary RVA nomenclature. Although 36 G types and 51 P types are presently known, most RVA infections in humans worldwide are related to five G/P combinations: G1P[8], G2P[4], G3P[8], G4P[8], G9P[8].AimThis study aimed to characterise the RVA strains circulating in Italy in the pre-vaccination era, to define the trends of circulation of genotypes in the Italian paediatric population.MethodsBetween September 2014 and August 2017, after routine screening in hospital by commercial antigen detection kit, 2,202 rotavirus-positive samples were collected in Italy from children hospitalised with AGE; the viruses were genotyped following standard European protocols.ResultsThis 3-year study revealed an overall predominance of the G12P[8] genotype (544 of 2,202 cases; 24.70%), followed by G9P[8] (535/2,202; 24.30%), G1P[8] (459/2,202; 20.84%) and G4P[8] (371/2,202; 16.85%). G2P[4] and G3P[8] genotypes were detected at low rates (3.32% and 3.09%, respectively). Mixed infections accounted for 6.49% of cases (143/2,202), uncommon RVA strains for 0.41% of cases (9/2,202).ConclusionsThe emergence of G12P[8] rotavirus in Italy, as in other countries, marks this genotype as the sixth most common human genotype. Continuous surveillance of RVA strains and monitoring of circulating genotypes are important for a better understanding of rotavirus evolution and genotype distribution, particularly regarding strains that may emerge from reassortment events.

Characterization of a novel plasmid encoding F4-like fimbriae present in a Shiga-toxin producing enterotoxigenic Escherichia coli isolated during the investigation on a case of hemolytic-uremic syndrome.

In February 2017 a case of Hemolytic-Uremic Syndrome (HUS) was reported to the National Registry of HUS in an adult living in Northern Italy. Stool specimens from the patient and his family contacts were collected and the analyses led to the isolation of a Locus of Enterocyte Effacement (LEE)-negative Shiga toxin 2 (Stx2)-producing Escherichia coli. The epidemiological investigations performed brought to collect fecal samples from the animals reared in a farm held by the case's family and a mixture of bovine and swine feces proved positive for Shiga toxin-producing E. coli (STEC) and yielded the isolation of a LEE-negative stx2-positive E. coli strain. Further characterization by whole genome sequencing led to identify the isolates as two identical O2:H27 hybrid Enterotoxigenic Shiga toxin-producing E. coli (ETEC-STEC). Sequencing of a high molecular weight plasmid present in the human isolate disclosed a peculiar plasmid harboring virulence genes characteristic for both pathotypes, including the enterohemolysin-coding gene and sta1, encoding the heat stable enterotoxin. Moreover, a complete fae locus encoding the ETEC F4 fimbriae could be identified, including a novel variant of faeG gene responsible for the production of the main structural subunit of the fimbriae. This novel faeG showed great diversity in the nucleotidic sequence when compared with the reference genes encoding the swine F4 allelic variants, whereas at the amino acid sequence level the predicted protein sequence showed some similarity with FaeG from E. coli strains of bovine origin. Further investigation on the plasmid region harboring the newly identified faeG allelic variant allowed to identify similar plasmids in NCBI sequence database, as part of the genome of other previously uncharacterized ETEC-STEC strains of bovine origin, suggesting that the novel F4-like fimbriae may play a role in bovine host specificity.

Molecular characterisation of human Shiga toxin-producing Escherichia coli O26 strains: results of an outbreak investigation, Romania, February to August 2016.

IntroductionAt the beginning of 2016, an increase in paediatric haemolytic uremic syndrome (HUS) cases was observed in Romania. The microbiological investigations allowed isolation of Shiga toxin-producing Escherichia coli (STEC) O26 as the causative agent from most cases. Methods: An enhanced national surveillance of HUS and severe diarrhoea was established across the country following the identification of the first cases and was carried out until August 2016. A total of 15 strains were isolated from 10 HUS and five diarrhoea cases. Strains were characterised by virulence markers (i.e. stx type/subtype, eae, ehxA genes), phylogroup, genetic relatedness and clonality using PCR-based assays, PFGE and multilocus sequence typing (MLST). The first six strains were further characterised by whole genome sequencing (WGS). Results: Five PCR-defined genotypes were distinguished. All strains from HUS cases harboured stx2a and eae, with or without stx1a, while strains from diarrhoea cases carried exclusively stx1a and eae genes. PFGE resolved strains into multiple pulsotypes, compatible with a certain geographic segregation of the cases, and strains were assigned to phylogroup B1 and sequence type (ST) 21. WGS confirmed the results of conventional molecular methods, brought evidence of O26:H11 serotype, and complemented the virulence profiles. Discussion/conclusion: This first description of STEC O26 strains from cases in Romania showed that the isolates belonged to a diverse population. The virulence content of most strains highlighted a high risk for severe outcome in infected patients. Improving the national surveillance strategy for STEC infections in Romania needs to be further considered.

Early findings in outbreak of haemolytic uraemic syndrome among young children caused by Shiga toxin-producing Escherichia coli, Romania, January to February 2016.

As at 29 February 2016, 15 cases of haemolytic uraemic syndrome with onset between 25 January and 22 February were reported among children between five and 38 months in Romania, and three of them died. Cases were mostly from southern Romania. Six cases tested positive for Escherichia coli O26 by serology. Fruits, vegetables, meat and dairy products were among the possible common food exposures. Investigations are ongoing in Romania to control the outbreak.

Community-wide outbreak of haemolytic uraemic syndrome associated with Shiga toxin 2-producing Escherichia coli O26:H11 in southern Italy, summer 2013.

In summer 2013, an excess of paediatric cases of haemolytic uraemic syndrome (HUS) in a southern region of Italy prompted the investigation of a community-wide outbreak of Shiga toxin 2-producing Escherichia coli (STEC) O26:H11 infections. Case finding was based on testing patients with HUS or bloody diarrhoea for STEC infection by microbiological and serological methods. A case-control study was conducted to identify the source of the outbreak. STEC O26 infection was identified in 20 children (median age 17 months) with HUS, two of whom reported severe neurological sequelae. No cases in adults were detected. Molecular typing showed that two distinct STEC O26:H11 strains were involved. The case-control study showed an association between STEC O26 infection and consumption of dairy products from two local plants, but not with specific ready-to-eat products. E.coli O26:H11 strains lacking the stx genes were isolated from bulk milk and curd samples, but their PFGE profiles did not match those of the outbreak isolates. This outbreak supports the view that infections with Stx2-producing E. coli O26 in children have a high probability of progressing to HUS and represent an emerging public health problem in Europe.

Outbreak of unusual Salmonella enterica serovar Typhimurium monophasic variant 1,4 [5],12:i:-, Italy, June 2013 to September 2014.

Monophasic variant of Salmonella enterica subspecies enterica serovar Typhimurium (monophasic S. Typhimurium), with antigenic structure 1,4,[5],12:i:-, appears to be of increasing importance in Europe. In Italy, monophasic S. Typhimurium represented the third most frequent Salmonella serovar isolated from human cases between 2004 and 2008. From June 2013 to October 2014, a total of 206 human cases of salmonellosis were identified in Abruzzo region (Central Italy). Obtained clinical isolates characterised showed S. Typhimurium 1,4,[5],12:i:- with sole resistance to nalidixic acid, which had never been observed in Italy in monophasic S. Typhimurium, neither in humans nor in animals or foods. Epidemiological, microbiological and environmental investigations were conducted to try to identify the outbreak source. Cases were interviewed using a standardised questionnaire and microbiological tests were performed on human as well as environmental samples, including samples from fruit and vegetables, pigs, and surface water. Investigation results did not identify the final vehicle of human infection, although a link between the human cases and the contamination of irrigation water channels was suggested.

Serum Shiga toxin 2 values in patients during acute phase of diarrhoea-associated haemolytic uraemic syndrome.

AIM: Shiga toxins are delivered via systemic circulation and are considered to be the cause of diarrhoea-associated haemolytic uraemic syndrome (HUS), as they injure endothelial cells, particularly in the glomeruli. This study measured Shiga toxin 2 (Stx2) in the serum of children affected in by HUS due to Stx2 producing Escherichia coli. METHODS: The concentration of free Stx2 was measured in the serum of 16 children, collected immediately after admission to the clinic in the acute phase of HUS, using a sandwich enzyme-linked immunosorbent assay. The family members of two children were also investigated, with the relative toxicity of Stx2 assessed by a Vero cell-based fluorescent assay. RESULTS: Stx2 was found in the serum of eight of the 16 children who were investigated. It was also detected in four of the six family members not showing symptomatic HUS, with an extremely high level in two. CONCLUSION: An absent or rather low concentration of Stx2 was found in the serum of children admitted to the clinic with diarrhoea-associated HUS. The high concentration of Stx2 in family members without HUS, but mostly with watery diarrhoea and raised functional activity, was in line with the concept of early injury by Stx2.

One health adoption within prevention, preparedness and response to health threats: Highlights from a scoping review.

Introduction: As the COVID-19 pandemic has demonstrated, the complexity of factors involved in the emergence of health threats requires a holistic One Health (OH) approach to enhance the effectiveness of prevention, preparedness, and response (PPR) strategies. Therefore, we conducted a scoping review to explore how the OH approach has been adopted in the context of PPR strategies to health threats, and the challenges and benefits deriving from its integration. Methods: We defined the research questions and a strategy to guide the peer-reviewed and grey literature search to identify relevant articles and documents (identification). We assessed them for eligibility according to predefined criteria (screening) and finally included the ones that answered the research questions (inclusion). We performed a descriptive and thematic analysis of the results. Results: A total of 138 records were included in the review (57 from the peer-reviewed literature and 81 from the grey literature). The OH approach was mainly adopted in prevention strategies, particularly within the governance area. Human and animal health were the most integrated disciplines in the OH approach, while environmental and social sciences were the less integrated. The most targeted threats were antimicrobial resistance and zoonoses, with the African region being the most represented. Conducive factors for the adoption of OH PPR strategies were identified in resolutions and guidance emanating from international organisations. Discussion: The global governance of OH should utilise conducive factors, such as international resolutions and guidance, to enhance the adoption of multisectoral and multi-actor PPR strategies, that focus on national and international priorities and neglected threats, such as environmental hazards and pandemic risk. Integrated frameworks and metrics for the implementation and evaluation of OH PPR strategies need to be consolidated to contribute to the growing body of evidence supporting the adoption of the OH approach.

IRIDA-ARIES Genomics, a key player in the One Health surveillance of diseases caused by infectious agents in Italy.

Pathogen genomics is transforming surveillance of infectious diseases, deepening our understanding of evolution and diffusion of etiological agents, host-pathogen interactions and antimicrobial resistance. This discipline is playing an important role in the development of One Health Surveillance with public health experts of various disciplines integrating methods applied to pathogen research, monitoring, management and prevention of outbreaks. Especially with the notion that foodborne diseases may not be transmitted by food only, the ARIES Genomics project aimed to deliver an Information System for the collection of genomic and epidemiological data to enable genomics-based surveillance of infectious epidemics, foodborne outbreaks and diseases at the animal-human interface. Keeping in mind that the users of the system comprised persons with expertise in a wide variety of domains, the system was expected to be used with a low learning curve directly by the persons target of the analyses' results, keeping the information exchange chains as short as possible. As a result, the IRIDA-ARIES platform (https://irida.iss.it/) provides an intuitive web-based interface for multisectoral data collection and bioinformatic analyses. In practice, the user creates a sample and uploads the Next-generation sequencing reads, then an analysis pipeline is launched automatically performing a series of typing and clustering operations fueling the information flow. Instances of IRIDA-ARIES host the Italian national surveillance system for infections by Listeria monocytogenes (Lm) and the surveillance system for infections by Shigatoxin-producing Escherichia coli (STEC). As of today, the platform does not provide tools to manage epidemiological investigations but serves as an instrument of aggregation for risk monitoring, capable of triggering alarms on possible critical situations that might go unnoticed otherwise.

Assessment of the genetic susceptibility of sheep to scrapie by protein misfolding cyclic amplification and comparison with experimental scrapie transmission studies.

The susceptibility of sheep to scrapie is influenced mainly by the prion protein polymorphisms A136V, R154H, and Q171R/H. Here we analyzed the ability of protein misfolding cyclic amplification (PMCA) to model the genetic susceptibility of sheep to scrapie. For this purpose, we studied the efficiency of brain homogenates from sheep with different PrP genotypes to support PrP(Sc) amplification by PMCA using an ARQ/ARQ scrapie inoculum. The results were then compared with those obtained in vivo using the same sheep breed, genotypes, and scrapie inoculum. Genotypes associated with susceptibility (ARQ/ARQ, ARQ/AHQ, and AHQ/ARH) were able to sustain PrP(Sc) amplification in PMCA reactions, while genotypes associated with resistance to scrapie (ARQ/ARR and ARR/ARR) were unable to support the in vitro conversion. The incubation times of the experimental infection were then compared with the in vitro amplification factors. Linear regression analysis showed that the efficiency of in vitro PrP(Sc) amplification of the different genotypes was indeed inversely proportional to their incubation times. Finally, the rare ARQK176/ARQK176 genotype, for which no in vivo data are available, was studied by PMCA. No amplification was obtained, suggesting ARQK176/ARQK176 as an additional genotype associated with resistance, at least to the isolate tested. Our results indicate a direct correlation between the ability of different PrP genotypes to undergo PrP(C)-to-PrP(Sc) conversion by PMCA and their in vivo susceptibility and point to PMCA as an alternative to transmission studies and a potential tool to test the susceptibility of numerous sheep PrP genotypes to a variety of prion sources.

Free-ranging red deer (Cervus elaphus) as carriers of potentially zoonotic Shiga toxin-producing Escherichia coli.

Shiga toxin-producing E. coli (STEC) are zoonotic foodborne pathogens of outmost importance and interest has been raised in recent years to define the potential zoonotic role of wildlife in STEC infection. This study aimed to estimate prevalence of STEC in free-ranging red deer (Cervus elaphus) living in areas with different anthropisation levels and describe the characteristics of strains in order to evaluate the potential risk posed to humans. Two-hundred one deer faecal samples collected in 2016-2018 from animals of Central Italian Alps were examined by bacteriological analysis and PCR screening of E. coli colonies for stx1, stx2 and eae genes. STEC strains were detected in 40 (19.9%) deer, with significantly higher prevalence in offspring than in yearlings. Whole genome analysis was performed to characterise a subset of 31 STEC strains. The most frequently detected serotype was O146:H28 (n = 10, 32.3%). Virulotyping showed different stx subtypes combinations, with stx2b-only (n = 15, 48.4%) being the most prevalent. All STEC lacked the eae gene but harbored additional virulence genes, particularly adhesins, toxins and/or other colonisation factors also described in STEC isolated from disease in humans. The most frequently detected genes were astA (n = 22, 71%), subAB (n = 21, 68%), iha (n = 26, 83.9%) and lpfA (n = 24, 77%). Four hybrid STEC/Enterotoxigenic E. coli strains were also identified. According to the most recent paradigm for pathogenicity assessment of STEC issued by the European Food Safety Authority, our results suggest that red deer are carriers of STEC strains that may have zoonotic potential, regardless of the anthropisation levels. Particular attention should be drawn to these findings while handling and preparing game meat. Furthermore, deer may release STEC in the environment, possibly leading to the contamination of soil and water sources.

Use of antimicrobials in companion animal practice: a retrospective study in a veterinary teaching hospital in Italy.

OBJECTIVES: To describe the use of antimicrobials in a veterinary teaching hospital for companion animals in Italy, with particular regard to the agreement with recommendations of prudent use METHODS: The study was conducted with a retrospective, cross-sectional design. The population under investigation included 18,905 cats and dogs that were referred to the hospital between 2000 and 2007. Two different samples of the clinical paper forms were randomly selected to estimate the prevalence of animals receiving an antimicrobial prescription and to describe the pattern of antimicrobials used in relation to the condition being treated. The proportion of antimicrobials prescribed accomplishing recommendations of prudent use was also estimated, as well as the level of agreement with specific, diagnosis-based guidelines for antimicrobial use. RESULTS: Broad-spectrum antimicrobials, including penicillins with ß-lactamase inhibitors, first-generation cephalosporins and fluoroquinolones, were the most frequently prescribed compounds. Antimicrobials prescribed with the support of microbiological analyses and susceptibility testing were less than 5%. Among the recommendation of prudent use, the availability of information from laboratory testing had the poorest degree of agreement, while the other evaluated items were accomplished in most of the cases. CONCLUSIONS: Our results highlight the need to improve the procedures of antimicrobial prescription in the study setting. This can be achieved by supporting the guidance for antimicrobial use at the local level, with the adoption of specific guidelines, and at the national level with a further implementation of the policies of prudent prescriptions.

Quantitative Methods for the Prioritization of Foods Implicated in the Transmission of Hepatititis E to Humans in Italy.

Hepatitis E is considered an emerging foodborne disease in Europe. Several types of foods are implicated in the transmission of the hepatitis E virus (HEV) to humans, in particular, pork and wild boar products. We developed a parametric stochastic model to estimate the risk of foodborne exposure to HEV in the Italian population and to rank the relevance of pork products with and without liver (PL and PNL, respectively), leafy vegetables, shellfish and raw milk in HEV transmission. Original data on HEV prevalence in different foods were obtained from a recent sampling study conducted in Italy at the retail level. Other data were obtained by publicly available sources and published literature. The model output indicated that the consumption of PNL was associated with the highest number of HEV infections in the population. However, the sensitivity analysis showed that slight variations in the consumption of PL led to an increase in the number of HEV infections much higher than PNL, suggesting that PL at an individual level are the top risky food. Uncertainty analysis underlined that further characterization of the pork products preparation and better assessment of consumption data at a regional level is critical information for fine-tuning the most risky implicated food items in Italy.

Hepatitis E Virus Occurrence in Pigs Slaughtered in Italy.

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.