Persistence of hepatitis E virus (HEV) subtypes 3c and 3e: Long-term cold storage and heat treatments

Hepatitis E virus (HEV) is the causative agent of foodborne infections occurring in high income countries mainly by consumption of undercooked and raw pork products. The virus is zoonotic with pigs and wild boars as the main reservoirs. Several studies proved the presence of HEV-RNA in pork liver sausages, pâté and other pork by-products. However, the detection of HEV nucleic acids does not necessary correspond to infectious virus and information on the persistence of the virus in the food is still limited. To which extent and how long the virus can survive after conventional industrial and home-made conservation and cooking procedures is largely unknown. In the present study, we investigated the persistence of two subtypes of HEV-3, by measuring the viral RNA on cell supernatant of infected A549 cells, after long-term storage at +4 °C and -20 °C and after heating for short or long-time span. Results confirmed that either low temperature storage (+4 °C) or freezing (-20 °C) do not influence the survival of the virus, and only a moderate reduction of presence of its RNA after 12 weeks at +4 °C was observed. To the other side, heating at 56 °C for long time (1 h) or at higher temperatures (>65 °C) for shorter time inactivated the virus successfully.

Investigation of Salmonella, hepatitis E virus (HEV) and viral indicators of fecal contamination in four Italian pig slaughterhouses, 2021-2022

In the pork production chain, the control at slaughterhouse aims to ensure safe food thanks to proper hygienic conditions during all steps of the slaughtering. Salmonella is one of the main foodborne pathogens in the EU causing a great number of human cases, and pigs also contribute to its spreading. Pig is the main reservoir of the zoonotic hepatitis E virus (HEV) that can be present in liver, bile, feces and even rarely in blood and muscle. The aim of this study was to assess the presence of both Salmonella and HEV in several points of the slaughtering chain, including pig trucks. Other viruses hosted in the gut flora of pigs and shed in feces were also assayed (porcine adenovirus PAdV, rotavirus, norovirus, and mammalian orthoreovirus MRV). Torque teno sus virus (TTSuV) present in both feces, liver and blood was also considered. Four Italian pig abattoirs were sampled in 12 critical points, 5 of which were the outer surface of carcasses before processing. HEV and rotavirus (RVA) were not detected. Norovirus was detected once. Salmonella was detected in two of the 4 abattoirs: in the two lairage pens, in the site of evisceration and on one carcass, indicating the presence of Salmonella if carcass is improper handled. The sampling sites positive for Salmonella were also positive for PAdV. MRV was detected in 10 swabs, from only two abattoirs, mainly in outer surface of carcasses. TTSuV was also detected in all abattoirs. Our study has revealed a diverse group of viruses, each serving as indicator of either fecal (NoV, RVA, PAdV, MRV) or blood contamination (TTSuV). TTSuV could be relevant as blood contamination indicators, crucial for viruses with a viremic stage, such as HEV. The simultaneous presence of PAdV with Salmonella is relevant, suggesting PAdV as a promising indicator for fecal contamination for both bacterial and viruses. In conclusion, even in the absence of HEV, the widespread presence of Salmonella at various points in the chain, underscores the need for vigilant monitoring and mitigation strategies which could be achieved by testing not only bacteria indicators as expected by current regulation, but also some viruses (PAdV, TTSuV, MRV) which could represent other sources of fecal contamination.

A Review of Slaughter Practices and Their Effectiveness to Control Microbial - esp. Salmonella spp. - Contamination of Pig Carcasses

The BIOPIGEE project (part of the One Health European Joint Programme under Horizon 2020) aimed to identify relevant measures to effectively control Salmonella, and another zoonotic pathogen, hepatitis E virus (HEV) within the pig meat food chain. The aim of this study was to identify biosecurity measures or management practices that are relevant for limiting Salmonella and/or HEV occurrence and spread within pig slaughterhouses. This was with the final goal of compiling a list of biosecurity measures for different processes and operations along the slaughter line with evidence of their effectiveness. To achieve this, a literature review was conducted on studies estimating the effectiveness of measures applied in slaughterhouses to reduce the microbial contamination of pig carcasses. Results of this literature search are discussed and presented in summary tables that could be used as a source of information for the pig slaughter industry to further develop their guidelines on hygienic slaughter.

Tracking the Selective Pressure Profile and Gene Flow of SARS-CoV-2 Delta Variant in Italy from April to October 2021 and Frequencies of Key Mutations from Three Representative Italian Regions

The SARS-CoV-2 Delta variant of concern (VOC) was often associated with serious clinical course of the COVID-19 disease. Herein, we investigated the selective pressure, gene flow and evaluation on the frequencies of mutations causing amino acid substitutions in the Delta variant in three Italian regions. A total of 1500 SARS-CoV-2 Delta genomes, collected in Italy from April to October 2021 were investigated, including a subset of 596 from three Italian regions. The selective pressure and the frequency of amino acid substitutions and the prediction of their possible impact on the stability of the proteins were investigated. Delta variant dataset, in this study, identified 68 sites under positive selection: 16 in the spike (23.5%), 11 in nsp2 (16.2%) and 10 in nsp12 (14.7%) genes. Three of the positive sites in the spike were located in the receptor-binding domain (RBD). In Delta genomes from the three regions, 6 changes were identified as very common (>83.7%), 4 as common (>64.0%), 21 at low frequency (2.1%-25.0%) and 29 rare (≤2.0%). The detection of positive selection on key mutations may represent a model to identify recurrent signature mutations of the virus.

First serological and molecular investigation of hepatitis E virus infection in dromedary camels in Algeria

Hepatitis E is an acute self-limited or fulminant infection in humans, caused by the hepatitis E virus (HEV). This member of the Hepeviridae family has been identified in a wide range of domestic and wild animals all over the world, with a possible transmission to humans through fecal oral route, direct contact and ingestion of contaminated meat products, making it one of the global zoonotic and public health major concerns. Since there is no monitoring program and a lack of data on HEV in animals in Algeria, the current preliminary survey has been undertaken to elucidate the exposure to the virus in camels at abattoirs of six southern provinces of Algeria. Two-hundred and eight sera/plasma were collected and analyzed (by double antigen sandwich ELISA) for the presence of total anti-HEV antibodies, among which 35.1% were positive, but no HEV RNA could be isolated from them (by two pan-HEV nested RT-PCR and broad range real-time reverse transcription RT-PCR). The univariate analysis showed significant associations (p < 0.05) between HEV seroprevalence and province of origin, age, and sex of camels, whereas the multivariable logistic regression analysis revealed a negative impact of camels' age on it. The obtained results confirm that HEV infection is widespread established in the camelid population of Algeria.

Hepatitis E Virus (HEV) in Heavy Pigs in Slaughterhouses of Northern Italy: Investigation of Seroprevalence, Viraemia, and Faecal Shedding

Hepatitis E virus (HEV) is considered an emerging threat in Europe, owing to the increased number of human cases and the widespread presence of the virus in pigs at farms. Most cases in industrialized countries are caused by the zoonotic HEV-3 genotype. The main transmission route of HEV-3 in Europe is foodborne, through consumption of raw or undercooked liver pork and wild boar meat. Pigs become susceptible to HEV infection after the loss of maternal immunity, and the majority of adult pigs test positive for IgG anti-HEV antibodies. Nonetheless, HEV-infected pigs in terms of liver, faeces, and rarely blood are identified at slaughterhouses. The present study aimed to investigate the prevalence of HEV-positive batches of Italian heavy pigs at slaughterhouses, assessing the presence of animals still shedding HEV upon their arrival at the slaughterhouse by sampling faeces collected from the floor of the trucks used for their transport. The occurrence of viraemic animals and the seroprevalence of anti-HEV antibodies were also assessed. The results obtained indicated the presence of anti-HEV IgM (1.9%), and a high seroprevalence of anti-HEV total antibodies (IgG, IgM, IgA; 89.2%, n = 260). HEV RNA was not detected in either plasma or faecal samples. Nevertheless, seropositive animals were identified in all eight batches investigated, confirming the widespread exposure of pigs to HEV at both individual and farm levels. Future studies are needed to assess the factors associated with the risk of HEV presence on farms, with the aim to prevent virus introduction and spread within farms, thereby eliminating the risk at slaughterhouse.

Erinaceus coronavirus persistence in hedgehogs (Erinaceus europaeus) in a non-invasive, in vivo, experimental setting

In the last 20 years, new zoonotic CoV strains have emerged (SARS-CoV, MERS-CoV, and SARS-CoV-2), and new species have also been reported in animals. In Europe, the Erinaceus coronavirus (EriCoV) was recently described in Erinaceus europaeus. However, information on the prevalence and duration of viral shedding is unknown. In this study, feces samples were collected from 102 European hedgehogs hosted in the Center for the Recovery of Wild Fauna in Rome and analyzed for the presence of EriCoV RNA by Reverse Transcription-PCR. In total, 45 animals (44.1%) resulted positive for EriCoV at the first sampling and 63 (61.7%) animals were positive at the follow-up, which was performed from the 3rd to the 86th day. The duration of fecal virus shedding showed a mean duration of 22.8 days and lasted up to 62 days. Eighteen hedgehogs showed intermittent viral shedding. Phylogenetic analysis showed a correlation with EriCoV strains reported in Germany, the United Kingdom, and northern Italy. None of the EriCoV sequences showed the CD200 ortholog insertion, previously observed in strains isolated in animals from northern Italy. Interestingly, all but one animal revealed the presence in their feces of the same EriCoV sequences, analyzing the short genomic region at 3' spike gene and 5' ORF3a 500bp fragment (100% nt.id.) in both first and follow-up samples. This result suggests that animals were infected with the same strain during their stay at the center. Our results confirm that EriCoV can persist in hedgehogs for a long period, underlining that hedgehogs are an important commensal reservoir for Merbecovirus. A long duration of viral shedding increases the likelihood that the virus will spread in the environment.

Assessing pig farm biosecurity measures for the control of Salmonella on European farms

Salmonella spp. is a common zoonotic pathogen, causing gastrointestinal infections in people. Pigs and pig meat are a major source of infection. Although farm biosecurity is believed to be important for controlling Salmonella transmission, robust evidence is lacking on which measures are most effective. This study enrolled 250 pig farms across nine European countries. From each farm, 20 pooled faecal samples (or similar information) were collected and analysed for Salmonella presence. Based on the proportion of positive results, farms were categorised as at higher or lower Salmonella risk, and associations with variables from a comprehensive questionnaire investigated. Multivariable analysis indicated that farms were less likely to be in the higher-risk category if they had '<400 sows'; used rodent baits close to pig enclosures; isolated stay-behind (sick) pigs; did not answer that the hygiene lock/ anteroom was easy to clean; did not have a full perimeter fence; did apply downtime of at least 3 days between farrowing batches; and had fully slatted flooring in all fattener buildings. A principal components analysis assessed the sources of variation between farms, and correlation between variables. The study results suggest simple control measures that could be prioritised on European pig farms to control Salmonella.

Detection of HEV RNA Using One-Step Real-Time RT-PCR in Farrow-to-Finish Pig Farms in Bulgaria

(1) Background: HEV is a zoonotic, foodborne pathogen. It is spread worldwide and represents a public health risk. The aim of this study was to evaluate the presence of HEV RNA in farrow-to-finish pig farms in different regions of Bulgaria; (2) Methods: Isolation of HEV RNA from pooled samples of feces was performed using a QIAamp^® Viral RNA Mini Kit followed by HEV RNA detection using a single-step real-time RT-PCR with primers and probes targeting the ORF 3 HEV genome; (3) Results: HEV RNA was detected in 12 out of 32 tested farms in Bulgaria (37.5%). The overall percentage of HEV-positive pooled fecal samples was 10.8% (68 of 630 samples). HEV was detected mostly in pooled fecal samples from finisher pigs (66/320, 20.6%) and sporadically from dry sows (1/62, 1.6%) and gilts (1/248, 0.4%); (4) Conclusions: Our results confirm that HEV circulates in farrow-to-finish pig farms in Bulgaria. In our study, we found HEV RNA in pooled fecal samples from fattening pigs (4-6-months age), shortly before their transport to the slaughterhouse indicating a potential risk to public health. The possible circulation of HEV throughout pork production requires monitoring and containment measures.

Absence of Hepatitis E Virus (HEV) in Italian Lagomorph Species Sampled between 2019 and 2021

The zoonotic hepatitis E virus genotype 3 (HEV-3) causes most autochthonous human hepatitis E cases in Europe, which are due to the consumption of raw or undercooked food products of animal origin. Pigs and wild boars are considered the main reservoirs of this genotype, while rabbits are the reservoir of a distinct phylogenetic group named HEV-3ra, which is classified within the HEV-3 genotype but in a separate clade. Evidence for the zoonotic potential of HEV-3ra was suggested by its detection in immunocompromised patients in several European countries. HEV-3ra infection was found in farmed and feral rabbit populations worldwide and its circulation was reported in a few European countries, including Italy. Furthermore, Italy is one of the major rabbit meat producers and consumers across Europe, but only a few studies investigated the presence of HEV in this reservoir. The aim of this study was to assess the presence of HEV in 328 Italian hares and 59 farmed rabbits collected in 3 Italian macro-areas (North, North-Central, and South-Central), between 2019 and 2021. For this purpose, liver samples were used to detect HEV RNA using broad-range real-time RT-PCR and nested RT-PCR. Using 28 liver transudates from hares, the ELISA test for anti-HEV IgG detection was also performed. Neither HEV RNA nor anti-HEV antibodies were detected. Further studies will be conducted to assess the HEV presence in Italian lagomorphs to establish the role of this host and the possible risk of transmission for workers with occupational exposure, to pet owners and via food.

Cross-sectional study of hepatitis E virus (HEV) circulation in Italian pig farms

Foodborne transmission is considered the main way of spreading zoonotic hepatitis E virus (HEV) infection in Europe. In recent years, the human cases of hepatitis E in subjects without history of travel in endemic areas have raised, suggesting that domestic HEV transmission is increasing. Pork products with or without liver, are often indicated as the source of many human foodborne HEV cases as well as small outbreaks. Pigs are recognized as the main reservoir of the zoonotic HEV-3 genotype, the most frequently detected in human cases in the EU. In the absence of a harmonized surveillance of HEV circulation, data on prevalence are heterogeneous but confirm a widespread circulation of HEV-3 in pig herds across EU. HEV-3 can pass through the food chain from farm to fork when infected animals are slaughtered. In Italy, several studies reported the circulation of HEV-3 in pig farms, but results are heterogeneous due to different methodologies applied. In the present study, we performed a survey over 51 pig herds belonging to three main types of farms: breeding, fattening and farrow-to-finish. HEV-RNA was analyzed by broad range Real-time RT-PCR on 20 samples for each farm, obtained by pooling together feces from 10 individuals. Overall, HEV RNA was confirmed on 150 fecal pooled samples out of 1,032 (14.5%). At least one positive pooled sample was detected from 18 farms out of 51 tested (35.3%). By lowering the number of infected pigs at primary production, the risk of HEV-3 entering into the food chain can be reduced. Hence, information on HEV circulation in herds is highly relevant for choosing preventive measures and deserves development of a monitoring program and further investigations.

Detection and whole genome sequencing of murine norovirus in animal facility in Italy

Viruses belonging to the genus Norovirus (NoV) of the family Caliciviridae are the major cause of acute viral gastroenteritis worldwide. NoVs are classified into 10 genogroups (GI-GX), and those belonging to the genogroup GV are able to infect several species of rodents. To evaluate the circulation of MNV among mice housed in an Italian facility, sampling was performed over two separate periods, in 2011, and 3 years later in 2014. During the two samplings, 75 fecal samples were collected from healthy mice housed in the animal facility and subjected to RT-PCR for viral detection. After the analysis, 41/75 animals (54.6%) resulted positive for the presence of MNV in feces. Nucleotide sequencing revealed the presence of two MNV variants co-circulating in both 2011 and 2014. One MNV strain was isolated on RAW264.7 cell line, and subjected to full genome sequencing. Our study showed that the murine noroviruses are widespread in the investigated animal facility, despite guidelines for animal care and maintenance. Full genome sequence analysis of the MNV strain described in this study showed a correlation with other strains circulating in Europe. Understanding the molecular epidemiology of this virus should give insight into its natural history and evolution in mice.

SARS-CoV-2 in a Mink Farm in Italy: Case Description, Molecular and Serological Diagnosis by Comparing Different Tests

This study described a SARS-CoV-2 infection in minks on an Italian farm. Surveillance was performed based on clinical examination and a collection of 1879 swabs and 74 sera from dead and live animals. The farm was placed under surveillance for 4.5 months, from the end of July 2020, when a man working on the farm tested positive by RT-PCR, till mid-December 2020 when all the animals were sacrificed. Clinical examination revealed no clinical signs or increased mortality rates attributable to SARS-CoV-2, while diagnostic tests detected only four weak PCR-positive samples, but 100% of sera were positive for SARS-CoV-2 anti-S antibodies. The phylogenetic analysis of two SARS-CoV-2 sequences from two minks and the sequence of the worker showed that they belonged to different clades. It could be therefore assumed that two distinct introductions of the virus occurred on the farm, and that the first introduction probably occurred before the start of the surveillance period. From the data collected, and especially from the detection of specific antibodies through the combination of different tests, it can be postulated that syndromic surveillance combined with genome detection by PCR may not be sufficient to achieve a diagnosis in asymptomatic animals. In particular, the serological approach, especially when using tests directed towards the S protein, may be useful for improving the traceability of virus circulation in similar environments.

Torque Teno Sus Virus (TTSuV) Prevalence in Wild Fauna of Northern Italy

Torque teno sus virus (TTSuV) is a non-enveloped circular ssDNA virus which frequently infects swine and has been associated with hepatic, respiratory, and autoimmune disorders. TTSuV’s pathogenic role is still uncertain, and clear data in the literature on virus reservoirs are lacking. The aims of this study were to investigate the presence of potentially zoonotic TTSuV in wild animals in Northern Italy and to evaluate their role as reservoirs. Liver samples were collected between 2016 and 2020 during four hunting seasons from wild boars (Sus scrofa), red deer (Cervus elaphus), roe deer (Capreolus capreolus), and chamois (Rupicapra rupicapra). Samples originated from areas in Northern Italy characterized by different traits, i.e., mountains and flatland with, respectively low and high farm density and anthropization. Viral identification was carried out by end-point PCR with specific primers for TTSuV1a and TTSuVk2a species. TTSuV prevalence in wild boars was higher in the mountains than in the flatland (prevalence of 6.2% and 2.3%, respectively). In wild ruminants only TTSuVk2a was detected (with a prevalence of 9.4%). Our findings shed light on the occurrence and distribution of TTSuV in some wild animal species, investigating their possible role as reservoirs.

The role of staff and contaminated environmental surfaces in spreading of norovirus infection in a long-term health care facility in Italy

Some residents and people from the staff of a geriatric health care facility in Teramo province, developed acute gastroenteritis from March 8th to March 21st 2017. A prompt epidemiological investigation was conducted to identify the etiological agent, the trace back the potential ways of transmission and control the infection. Information on the outbreak was collected through an epidemiological questionnaire. Faecal samples from all human cases (n = 50) and swabs from environmental surfaces were collected and analysed by RT-PCR for the presence of Norovirus (NoV). Among faecal samples, 34 out of 50 were positive for NoV with no other pathogen detected. In particular, 2 (2/34) were positive to NoV genogroup I (GI), 31 (31/34) to NoV genogroup II (GII), and one sample (1/34) was positive to both NoV GI and GII. Moreover, faecal samples of people from the canteen (n = 8) were also tested resulting negative to NoV detection. Norovirus was also detected in 28 of the 122 swabs from environmental surfaces collected. Among the positive samples, 12 NoV strains were subtyped as NoV GII.4 Sydney_2012 variant. Person-to-person close contact and contaminated environmental surfaces were the probable transmission route among the people of the health care facility. The members of the staff were considered to play an important role in transmission of NoV. A proper disinfection procedure applied during the outbreak could have been critically important to limit the dissemination of the viral infection.

Detection of antibodies against influenza D virus in swine veterinarians in Italy in 2004

Influenza D virus (IDV) was first isolated from a swine with respiratory disease symptoms in 2011 in the United States. Epidemiological and serological studies support the hypothesis that cattle represent the natural reservoir of IDV with periodical spillover events to other animal hosts. Little is known about the seroprevalence in humans and in specific target groups such as veterinarians in Italy. This study was designed to assess the prevalence of antibodies against two influenza D lineages (D/660 and D/OK) in Italy in archived serum samples from veterinarians working with swine collected in 2004. Serum samples were tested by haemagglutination inhibition (HI) and virus neutralization (VN) assays. Results showed that 4.88% (4/82) of tested samples were positive for D/660 and 2.44% (2/82) for D/OK by HI assay. Three out of four samples showed positivity when tested by VN assay. Our data suggest undetected IDVs might have circulated and/or been introduced in Italy as early as 2004 at least in some animal species such as swine. In addition, it seems that the virus was circulating among veterinarians before the first isolation in 2011. This finding highlights the importance to continue monitoring the IDV spread in animals and humans for more detailed surveillance.

Possible Human-to-Dog Transmission of SARS-CoV-2, Italy, 2020

We detected severe acute respiratory syndrome coronavirus 2 in an otherwise healthy poodle living with 4 family members who had coronavirus disease. We observed antibodies in serum samples taken from the dog, indicating seroconversion. Full-length genome sequencing showed that the canine and human viruses were identical, suggesting human-to-animal transmission.

Long-term surveillance for hepatitis E virus in an Italian two-site farrow-to-finish swine farm

In humans, hepatitis E virus (HEV) is responsible for an acute enterically transmitted hepatitis, which can become chronic in immune-compromised patients. Genotypes 3 and 4 (HEV-3 and HEV-4) are zoonotic, and domestic pigs and wild boar are the main reservoirs. The occurrence of autochthonous cases in Europe, which have been increasing over the last 10 years, has been associated with food-borne zoonotic transmission of HEV-3, mainly linked to consumption of undercooked or raw pork products (sausages containing liver) and wild boar meat. Zoonotic HEV-3 strains are widespread on pig farms, but little information is available on the dynamic of HEV-3 infection within farms, among pigs. The aims of this study were to evaluate the prevalence of the infection among pigs of different ages along the production chain by the zoonotic HEVs, and to evaluate how long the virus may persist in the farm environment. The presence of HEV-RNA was investigated by real-time reverse transcription PCR (RT-PCR) in 281 test faecal pools over 19 months (2017-2019) on a two-site farrow-to-finish farm (about 1,000 sows), in Northern Italy. A total of 67/281 test faecal pools (23.8%) resulted positive for the presence of HEV-RNA (site 1: 59/221, 26.7%; site 2: 8/60, 13.3%). Nucleotide sequencing revealed a unique HEV-3 viral variant circulating during 19 months of surveillance. The same HEV-3 strain was detected in the same farm on 2012, indicating the persistence of the same virus over 7 years, and highlighting the role of the environment as a continuous source of infection on pig farms. The results confirmed the circulation of the zoonotic genotype HEV-3 in pigs before slaughtering.

Can Coronaviruses Steal Genes from the Host as Evidenced in Western European Hedgehogs by EriCoV Genetic Characterization?

Due to their need for living cells, viruses have developed adaptive evolutionary strategies to survive and perpetuate in reservoir hosts that play a crucial role in the ecology of emerging pathogens. Pathogenic and potentially pandemic betacoronaviruses arose in humans in 2002 (SARS-CoV, disappeared in July 2003), 2012 (MERS-CoV, still circulating in Middle East areas), and 2019 (SARS-CoV-2, causing the current global pandemic). As universally recognized, bats host ancestors of the above-mentioned zoonotic viruses. However, hedgehogs have been recently identified in Europe and Asia as possible reservoirs of MERS-CoV-like strains classified as Erinaceus coronavirus (EriCoV). To elucidate the evolution and genetics of EriCoVs, NGS (next generation sequencing) and Sanger sequencing were used to examine fecal samples collected in Northern Italy in 2018/2019 from 12 hedgehogs previously found EriCoV-positive by RT-PCR. By sequence analysis, eight complete EriCoV genomes, obtained by NGS, showed a high phylogenetic correlation with EriCoV strains previously reported in Eurasia. Interestingly, eight viral strains presented an additional ORF encoding for the CD200 ortholog located between the genes encoding for the Spike and the ORF3a proteins. The CD200 ortholog sequences were closely similar to the host CD200 protein but varying among EriCoVs. The result, confirmed by Sanger sequencing, demonstrates for the first time that CoVs can acquire host genes potentially involved in the immune-modulatory cascade and possibly enabling the virus to escape the host defence.

Hepatitis E virus (HEV) genotype 3 diversity: Identification of a novel HEV subtype in wild boar in Central Italy

In the last decade in Europe, the number of autochthonous cases of hepatitis E has significantly increased. Most of the cases arise from foodborne infections caused by the zoonotic hepatitis E virus (HEV) genotypes HEV-3 and HEV-4. Several human cases have been linked to consumption of raw or undercooked animal products of both pork (liver sausages) and wild boar meat. In this study, the occurrence of HEV infection was investigated in 611 livers and 88 paired lungs from wild boars collected during the hunting seasons of 2016-2020 in the Umbria-Marche Apennines (Central Italy). Using real-time reverse transcription polymerase chain reaction, 15 liver samples (2.45%) and one lung sample were found to be positive for HEV RNA. The phylogenetic tree built on the partial ORF2 gene revealed that the detected HEV strains belonged to HEV-3f (n = 5), HEV-3e (n = 1) and HEV-3c (n = 1) subtypes. Interestingly, 8 strains were genetically placed in a different cluster, further away from all other subtypes. To corroborate this finding, four complete genomes were obtained by next generation sequencing. The full genome of the HEV strains clustered together with another wild boar strain previously detected in Southern Italy in 2015 but the strains were divergent from all the HEV-3 strains classified in any subtype defined so far. Thus, these strains represent a novel subtype that might have originated in Italy, which we have tentatively named HEV-3n.

Seroprevalence of Hepatitis E Virus in Forestry Workers from Trentino-Alto Adige Region (Northern Italy)

People with some occupational or recreational activities, such as hunters and veterinarians, may have increased risk to be infected by the hepatitis E virus (HEV). The aim of the present study was to establish whether forestry workers could be considered at a higher risk of HEV infection than a control group. One hundred and fifty sera from forestry workers and a control group of 85 sera were analysed by anti-HEV IgG antibodies detection using a commercial ELISA kit. The anti-HEV IgG seroprevalence was 14% for forestry workers and 9.4% for the control group. Comparing the risk of HEV infection in the two groups, there was no difference in the odds ratio. However, the seroprevalence in older subjects was higher in the forestry workers than in the control group. Two sera from forestry workers were also positive for anti-HEV IgM, and, in one of them, HEV-RNA was detected. Our findings showed an increase of seroprevalence with age, which is likely to reflect cumulative exposure to HEV over time. The occupation of forestry workers did not seem to be associated with a higher risk of HEV infection. The study provided new insights into the risk of acquiring HEV in occupational exposure workers with open-air activities.

Pilot Investigation on the Presence of Anti-Hepatitis E Virus (HEV) Antibodies in Piglet Processing Fluids

Simple Summary

Domestic and wild pigs are the main Hepatitis E virus (HEV) zoonotic reservoirs. Identifying HEV-positive pig farms is important to implement surveillance programs for this emerging zoonotic agent. The aim of this study was to evaluate the use of serosanguineous fluids obtained as part of castration practice (processing fluids (PFs)) to detect anti-HEV antibodies. Ninety-five paired serum and PF samples were collected from newborn piglets of 29 different litters and tested with a commercial ELISA kit. A significant positive correlation (Spearman’s rho: 0.600; p < 0.01) was found between the signal-to-cutoff (S/Co) ratio of anti-HEV antibodies in serum and PF samples. In 26 out of 29 litters (89.7%), there was at least one positive piglet in the serum. Sixteen litters out of 29 (55.2%) were also positive in PFs. The detection of anti-HEV maternal-derived antibodies in PFs confirms a past exposure of sows to the virus. PF may represent a rapid, noninvasive and economical tool to identify HEV-positive farms.

Abstract

Identifying Hepatitis E virus (HEV)-positive pig farms is important to implement surveillance programs for this emerging zoonotic agent. The aim of this study was to evaluate the use of serosanguineous fluids obtained as part of castration practice (processing fluids (PFs)) to detect anti-HEV antibodies in newborn piglets. Ninety-five paired serum and PF samples were collected from piglets of 29 different litters and tested with a commercial ELISA kit. A significant positive correlation (Spearman’s rho: 0.600; p < 0.01) was found between anti-HEV antibodies in serum and PF samples. In 26 out of 29 litters (89.7%), there was at least one positive piglet in the serum. Sixteen litters out of 29 (55.2%) were also positive in PFs. To simulate the use of PF as pooled samples, the limit of detection of the ELISA was assessed mixing the PF sample with strong, medium, medium-weak and weak ELISA titres with 3, 4, 5 and 6 negative PF samples. Our results suggest that it is still possible to identify a positive PF pool when at least one individual PF sample with medium or strong antibody levels is mixed with 5 or 6 individual negative PF samples. The detection of anti-HEV maternal-derived antibodies in PF confirms a past exposure of sows to the virus. PF may represent a rapid, noninvasive and economical tool to identify HEV-positive farms.

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

Introduction

Group 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].

Aim

This 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.

Methods

Between 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.

Results

This 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).

Conclusions

The 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.

Accumulation and Depuration Kinetics of Rotavirus in Mussels Experimentally Contaminated

Bivalve mollusks as filter-feeders concentrate in their digestive tissue microorganisms likely present in the harvesting water, thus becoming risky food especially if consumed raw or poorly cooked. To eliminate bacteria and viruses eventually accumulated, they must undergo a depuration process which efficacy on viruses is on debate. To better clarify the worth of the depuration process on virus elimination from mussels, in this study we investigated rotavirus kinetics of accumulation and depuration in Mytilus galloprovincialis experimentally contaminated. Depuration process was monitored for 9 days and virus residual presence and infectivity were evaluated by real time quantitative polymerase chain reaction, cell culture and electron microscopy at days 1, 2, 3, 5, 7, 9 of depuration. Variables like presence of ozone and of microalgae feeding were also analyzed as possible depuration enhancers. Results showed a two-phase virus removal kinetic with a high decrease in the first 24 h of depuration and 5 days necessary to completely remove rotavirus.

Detection of Hepatitis E Virus in Livers and Muscle Tissues of Wild Boars in Italy

In industrialized countries, hepatitis E is now recognized as an emerging zoonosis. Autochthonous cases have been increased over recent years in Europe and are mainly associated with HEV-3 infections. Pigs and wild boars are considered the main reservoirs of the zoonotic HEV-3 and HEV-4 genotypes. Over the past decade, the number of wild boars has drastically increased in Europe. Due to habitats closer to humans and domestic animals, the role of wild boar as a reservoir of the zoonotic HEV is considered to be an emerging issue. In this study, we investigated the presence of HEV RNA by a real-time RT-PCR assay in paired liver and muscle samples collected from 196 wild boars (Sus scrofa) hunted in the two areas of Central and Southern Italy. Twenty animals (10.2%) were HEV RNA positive in livers, 11 of which were also positive in muscles. The ORF2 and ORF1 partial viral sequences were obtained for nine paired livers and muscles, and when aligned were identical to each other. Phylogenetic analyses confirmed detection of different HEV-3 subtypes: 3c, 3f, 3i and some that were not assigned to any subtypes that have so far been identified. Results need further investigation because they are based on analyses of sequences of short genome regions. Nevertheless, we observed that the same strains were circulating in the wild boar populations from the two investigated areas, confirming persistence of the same HEV strains in the wild boar population over time.

Molecular Characterization of HEV Genotype 3 in Italy at Human/Animal Interface

Hepatitis E virus (HEV) is an emerging public health issue in industrialized countries. In the last decade the number of autochthonous human infections has increased in Europe. Genotype 3 (HEV-3) is typically zoonotic, being foodborne the main route of transmission to humans, and is the most frequently detected in Europe in both humans and animals (mainly pigs and wild boars). In Italy, the first autochthonous human case was reported in 1999; since then, HEV-3 has been widely detected in both humans and animals. Despite the zoonotic characteristic of HEV-3 is well established, the correlation between animal and human strains has been poorly investigated in Italy. In the present study, we compared the subtype distribution of HEV-3 in humans and animals (swine and wild boar) in the period 2000-2018 from Italy. The dataset for this analysis included a total of 96 Italian ORF2 sequences (300 nt long), including both NCBI database-derived (n = 64) and recent sequences (2016-2018, n = 32) obtained in this study. The results show that subtype 3f is the most frequent in humans and pigs, followed by the HEV-3e, HEV-3c and other unassignable HEV-3 strains. Diversely, in wild boar a wider group of HEV-3 subtypes have been detected, including HEV-3a, which has also been detected for the first time in a human patient in Central Italy in 2017, and a wide group of unassignable HEV-3 strains. The phylogenetic analysis including, besides Italian strains, also sequences from other countries retrieved from the NCBI database, indicated that human Italian sequences, in particular those of HEV-3f and HEV-3e, form significant clusters mainly with sequences of animal origin from the same country. Nevertheless, for HEV-3c, rarely detected in Italian pigs, human sequences from Italy are more correlated to human sequences from other European countries. Furthermore, clusters of near-identical human strains identified in a short time interval in Lazio Region (Central Italy) can be recognized in the phylogenetic tree, suggesting that multiple infections originating from a common source have occurred, and confirming the importance of sequencing support to HEV surveillance.

Occurrence of HEV-RNA in Italian Regional Pork and Wild Boar Food Products

Hepatitis E is an emerging threat in industrialized countries. The foodborne transmission linked to consumption of pork and game meat is considered the main source of autochthonous infection. In Europe, small outbreaks have been reported linked to the consumption of pork liver sausages and wild boar meat. Based on previous findings and on increasing evidence of pork and game meat as a vehicle for HEV infections, the present study investigated the occurrence of HEV in 99 pork and 63 wild boar sausages and salami sold in Southern Italy. The HEV genome was detected in four wild boar sausages. Sequencing from 2 wild boar sausages confirmed that the HEV strains detected belonged to HEV-3 genotype, not assigned to any defined subtype. Data obtained confirmed the possible occurrence of HEV in pork products and in game. Although the detection rate is low, these products are frequently consumed raw after curing, whose effect on virus viability is still unknown.

Detection of hepatitis E virus RNA in rats caught in pig farms from Northern Italy

Hepatitis E virus (HEV) strains belonging to the Orthohepevirus genus are divided into four species (A-D). HEV strains included in the Orthohepevirus A species infect humans and several other mammals. Among them, the HEV-3 and HEV-4 genotypes are zoonotic and infect both humans and animals, of which, pigs and wild boar are the main reservoirs. Viruses belonging to the Orthohepevirus C species (HEV-C) have been considered to infect rats of different species and carnivores. Recently, two studies reported the detection of HEV-C1 (rat HEV) RNA in immunocompromised and immunocompetent patients, suggesting a possible transmission of rat HEV to humans. The role of rats and mice as reservoir of HEV and the potential zoonotic transmission is still poorly known and deserves further investigation. To this purpose, in this study, the presence of HEV RNA was investigated in the intestinal contents and liver samples from 47 Black rats (Rattus rattus) and 21 House mice (Mus musculus) captured in four pig farms in Northern Italy. The presence of both Orthohepevirus A and C was investigated by the real-rime RT-PCR specific for HEV-1 to HEV-4 genotypes of Orthohepevirus A species and by a broad spectrum hemi-nested RT-PCR capable of detecting different HEV species including rat HEV. The intestinal content from two Black rats resulted positive for HEV-C1 RNA and for HEV-3 RNA, respectively. None of the House mice was HEV RNA positive. Sequence analyses confirmed the detection of HEV-C1, genotype G1 and HEV-3 subtype e. The viral strain HEV-3e detected in the rat was identical to swine HEV strains detected in the same farm. Liver samples were negative for the detection of either rat HEV or HEV-3.

Occurrence of two Norovirus outbreaks in the same cafeteria in one week

In October 2017, two outbreaks of gastroenteritis (GE) occurred among patrons of a cafeteria in Italy in one week. Virological and bacteria investigations on stool samples, environment and food were conducted to identify the infectious agents and the possible source of infection. Forty-five cases occurred in the two outbreaks, including 13 laboratory-confirmed cases of norovirus GI. Nine staff members were interviewed, six were confirmed positive for NoV GI and 3 experienced GE symptoms. Bacteria faecal indicators and other bacteria pathogens were not detected in either environmental swab samples or food. A low level of NoV GII was detected in two environmental swab samples. The same GI.6 strain was identified in cases related to both outbreaks, suggesting a common source of infection. Since the two outbreaks occurred in one week, the NoV contamination could have persisted in the cafeteria. Furthermore, virological investigation revealed confirmed cases among food handlers who had worked at the cafeteria between and during the two outbreaks. Several studies highlighted the importance of excluding symptomatic food handlers to prevent contamination of foods and environment.

Full genome characterization of two novel Alpha-coronavirus species from Italian bats

Coronaviruses (CoVs) have been detected worldwide in several bat species, which are considered the main reservoir. The attention to the high diversity of CoVs hosted by bats has increased during the last decade due to the high number of human infections caused by two zoonotic Beta-CoVs, SARS-CoV and MERS-CoV, that cause several respiratory diseases. Among coronaviruses, two Alpha-CoV strains (HuCoV-229E and HuCoV-NL63) cause mild respiratory disease that can change to severe disease in children, elderly and individuals affected by illnesses. Phylogenetic analysis conducted on bat Alpha-CoV strains revealed their evolutive correlation to human strains, suggesting their origin in bats. The genome of CoVs is characterized by a high frequency of mutations and recombination events, increasing their ability to switch hosts and their zoonotic potential. In this study, three strains of Alpha-CoV genera detected in Italian bats (Pipistrellus kuhlii) were fully sequenced by Next Generation Sequencing (NGS) and characterized. The complete genome analysis showed the correlation of the Italians strains with a Chinese strain detected in 2013 and, based on CoV molecular species demarcation, two new Alpha-CoV species were established. The analysis of a fragment of the RNA-dependent RNA polymerase (RdRp) showed the correlation of the Italian strains with CoVs that was only detected in the bat Pipistrellus genera (Pipistrellus kuhlii and Pipistrellus Pipistrellus) in European countries.

Molecular survey of HEV infection in wild boar population in Italy

Hepatitis E virus (HEV) is an RNA virus causing an acute generally self-limited disease in humans. An increasing number of autochthonous cases linked to zoonotic transmission of HEV genotype 3 have been reported over the last 10 years in Europe. Pigs and wild boars are considered the main reservoirs. The principal route of transmission in Europe is food-borne, linked by direct or indirect evidence to the consumption of raw or undercooked pork products and wild boar meat. In this study, we sampled 92 wild boar (Sus scrofa) livers during active surveillance in five municipalities in Central Italy throughout the hunting season 2016-2017. HEV RNA was detected in 52.2% of liver sampled with prevalence ranging from 0.0% to 65.7%. HEV-positive wild boars were detected in all but one area of hunting. Phylogenetic analysis showed that strains clustered within the two subtypes HEV-3c and HEV-3f and displayed a wide range of phylogenetic diversity. Several strains were circulating in the areas investigated; animals possibly belonging to the same family group hunted by the same team were infected with a unique strain (100% nucleotide identity). As wild animals are a proven source of HEV transmission to humans and pigs, the high prevalence observed (mean 52.2%) poses a question on the risk of consuming raw or undercooked wild boar meat, and thus, this subject deserves further investigations.

Molecular surveillance of norovirus, 2005-16: an epidemiological analysis of data collected from the NoroNet network

BACKGROUND

The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network.

METHODS

We included genetic sequences of norovirus specimens obtained from outbreak investigations and sporadic gastroenteritis cases between 2005 and 2016 in Europe, Asia, Oceania, and Africa. We genotyped norovirus sequences and analysed sequences that overlapped at open reading frame (ORF) 1 and ORF2. Additionally, we assessed the sampling date and country of origin of the first reported sequence to assess when and where novel drift variants originated.

FINDINGS

We analysed 16 635 norovirus sequences submitted between Jan 1, 2005, to Nov 17, 2016, of which 1372 (8·2%) sequences belonged to genotype GI, 15 256 (91·7%) to GII, and seven (<0·1%) to GIV.1. During this period, 26 different norovirus capsid genotypes circulated and 22 different recombinant genomes were found. GII.4 drift variants emerged with 2-3-year periodicity up to 2012, but not afterwards. Instead, the GII.4 Sydney capsid seems to persist through recombination, with a novel recombinant of GII.P16-GII.4 Sydney 2012 variant detected in 2014 in Germany (n=1) and the Netherlands (n=1), and again in 2016 in Japan (n=2), China (n=8), and the Netherlands (n=3). The novel GII.P17-GII.17, first reported in Asia in 2014, has circulated widely in Europe in 2015-16 (GII.P17 made up a highly variable proportion of all sequences in each country [median 11·3%, range 4·2-53·9], as did GII.17 [median 6·3%, range 0-44·5]). GII.4 viruses were more common in outbreaks in health-care settings (2239 [37·2%] of 6022 entries) compared with other genotypes (101 [12·5%] of 809 entries for GI and 263 [13·5%] of 1941 entries for GII non-GII.Pe-GII.4 or GII.P4-GII.4).

INTERPRETATION

Continuous changes in the global norovirus genetic diversity highlight the need for sustained global norovirus surveillance, including assessment of possible immune escape and evolution by recombination, to provide a full overview of norovirus epidemiology for future vaccine policy decisions.

FUNDING

European Union's Horizon 2020 grant COMPARE, ZonMw TOP grant, the Virgo Consortium funded by the Dutch Government, and the Hungarian Scientific Research Fund.

Public health risks associated with hepatitis E virus (HEV) as a food-borne pathogen

Hepatitis E virus (HEV) is an important infection in humans in EU/EEA countries, and over the last 10 years more than 21,000 acute clinical cases with 28 fatalities have been notified with an overall 10-fold increase in reported HEV cases; the majority (80%) of cases were reported from France, Germany and the UK. However, as infection in humans is not notifiable in all Member States, and surveillance differs between countries, the number of reported cases is not comparable and the true number of cases would probably be higher. Food-borne transmission of HEV appears to be a major route in Europe; pigs and wild boars are the main source of HEV. Outbreaks and sporadic cases have been identified in immune-competent persons as well as in recognised risk groups such as those with pre-existing liver damage, immunosuppressive illness or receiving immunosuppressive treatments. The opinion reviews current methods for the detection, identification, characterisation and tracing of HEV in food-producing animals and foods, reviews literature on HEV reservoirs and food-borne pathways, examines information on the epidemiology of HEV and its occurrence and persistence in foods, and investigates possible control measures along the food chain. Presently, the only efficient control option for HEV infection from consumption of meat, liver and products derived from animal reservoirs is sufficient heat treatment. The development of validated quantitative and qualitative detection methods, including infectivity assays and consensus molecular typing protocols, is required for the development of quantitative microbial risk assessments and efficient control measures. More research on the epidemiology and control of HEV in pig herds is required in order to minimise the proportion of pigs that remain viraemic or carry high levels of virus in intestinal contents at the time of slaughter. Consumption of raw pig, wild boar and deer meat products should be avoided.

Prevalence of Foodborne Viruses in Mussels in Southern Italy

In this study, the prevalence of various enteric viruses in Mytilus galloprovincialis (Mediterranean mussel) belonging to class A and class B mollusc-harvesting areas in the Campania region in southern Italy was evaluated. One hundred and eight mussels were analysed using real-time reverse transcription PCR during a 2-year collection period (2014-2015) to detect the following viruses: human norovirus (genogroups I and II), rotavirus, astrovirus, sapovirus, aichivirus, hepatitis A virus and hepatitis E virus. Overall, 50.93% of mussels were contaminated by at least one of the tested viruses. Of these virus-positive mussels, 63.63% were contaminated by two or more viruses. In 2014, only three of the eight investigated viruses were detected: astrovirus, sapovirus and aichivirus, whereas in 2015, seven of the eight viruses were detected (only hepatitis E virus was not identified). Astrovirus was the most frequently detected virus in both sampling periods. In 2014, sapovirus was detected at the same frequency as astrovirus (16.00%), followed by aichivirus (8%). In 2015, astrovirus (32.53%) was most frequently detected, followed by norovirus GII (26.50%), sapovirus (18.07%), hepatitis A virus (16.87%), rotavirus (16.87%), aichivirus (13.25%) and norovirus GI (12.05%).This study describes, for the first time, the presence of aichivirus and sapovirus in mussels in Italy.

Detection of Torque Teno Sus Virus in Pork Bile and Liver Sausages

Torque teno viruses (TTV) are small DNA viruses widespread among humans and pigs. The clinical significance of TTV infections in either humans or pigs is uncertain. In fact, TTV viremia is highly prevalent in patients with different pathologies, but it can also be frequently observed in healthy subjects. Virus infection in pigs is considered a putative cofactor in several diseases; despite being detected frequently in healthy animals, its role still remains unknown. The present study aimed to investigate the presence of Torque teno sus virus (TTSuV) in 62 bile samples collected from pigs at slaughterhouse and in 36 fresh pork liver sausages bought at point of sale. Quantitative Real-Time PCR, confirmed that 19.4 and 58.3 % of bile and sausage samples tested positive for TTSuV, respectively. The mean viral load was established as 5.6 × 10⁴ GE/µl for bile and 7.16 × 10³ GE/g for sausages. TTSuV nucleotide sequence analysis confirmed a wide heterogeneity among the circulating TTSuV strains, which included both TTSuV1 and TTSuV2.

Waterborne norovirus outbreak during a summer excursion in Northern Italy

In September 2011, an acute gastroenteritis outbreak affected 33 children in Northern Italy. Patients had drunk river water during an excursion. Identical GI.4 norovirus genomes were detected from one patient's stools and from the river water. Improper discharge of human sewage into the river may have caused this waterborne outbreak.

Investigation and control of a Norovirus outbreak of probable waterborne transmission through a municipal groundwater system

During March 2011 an outbreak of gastroenteritis occurred in Santo Stefano di Quisquina, Agrigento, Sicily, Italy. Within two weeks 156 cases were identified among the 4,965 people living in the municipality. An epidemiological investigation was conducted to characterize the outbreak and target the control measures. A case was defined as a person developing diarrhea or vomiting during February 27-March 13, 2011. Stool specimens were collected from 12 cases. Norovirus (NoV) genotype GII.4 variant New Orleans 2009 was identified in stool samples from 11 of 12 cases tested (91.7%). Epidemiological investigations suggested a possible association with municipal drinking water consumption. Water samples from the public water system were tested for NoV and a variety of genotypes were detected during the first 3 months of surveillance, including GII.4 strains belonging to different variants from that involved in the gastroenteritis outbreak. Contamination of the well and springs supplying the public water network was eventually thought to be the source of the NoV contamination.

Detection of serum antibodies to hepatitis E virus in domestic pigs in Italy using a recombinant swine HEV capsid protein

BACKGROUND

The hepatitis E virus (HEV) has been detected in both humans and animals, particularly pigs, worldwide. Several evidences, including human infection following consumption of raw contaminated meat, suggest a zoonotic transmission of HEV. In Italy, large circulation of genotype 3 HEV has been reported in swine, and recent studies have confirmed the involvement of this genotype in autochthonous human cases.

RESULT

In this study 111 sera collected from healthy pigs in two Italian regions were tested for anti-HEV IgG antibodies. For specific HEV antibody detection in swine, we developed ELISA and Western blotting methods, using a truncated capsid (ORF2) protein lacking the first 111 amino acids of a swine HEV genotype 3 strain. The ORF2-based ELISA revealed anti-HEV antibodies in 104 out of 111 pigs compared with 102 detected with a commercial ELISA kit. A lower number of sera reacted with the recombinant ORF2 protein in a Western blotting format (81/111). Using a Latent class analysis (LCA), the estimated sensitivities for ELISA-ORF2 and ELISA-kit tests were 0.961 and 0.936, respectively, whereas specificities were 0.599 and 0.475. The estimated sensitivity of Western blotting was 0.775, and the specificity was 0.944.

CONCLUSIONS

The overall results confirm the high prevalence of HEV seropositive healthy pigs in Italy. Through comparisons with a commercial ELISA test, the swine genotype 3 HEV antigen produced in this study was proven suitable to detect anti-HEV antibodies in pig sera by both ELISA and Western Blotting.

Zoonotic transmission of hepatitis E virus in industrialized countries

Hepatitis E is an infectious viral disease with clinical and morphological features of acute hepatitis. The disease represents an important public health problem in developing countries, where it is often related to outbreaks mainly associated with consumption of contaminated water. During recent years, an increasing number of sporadic cases have also been described in industrialized countries. Besides humans, the hepatitis E virus (HEV) has also been identified in animals. In 1997, the virus was first detected in swine, and is now considered ubiquitous. Human and swine HEV strains from the same geographical region present a high level of nucleotide identity, and experimental infections have confirmed the cross-species transmission of swine strains to humans and of human strains to non-human primates. Studies on anti-HEV antibodies detection have demonstrated that people working in contact with swine or wild boar have a higher risk of infection than normal blood donors. In Japan and more recently in France, cases of hepatitis E have been associated with ingestion of uncooked meat from pigs, wild boar, or deer. The disease is currently considered an emerging zoonosis.

Identification and Genotyping of Human Sapoviruses Collected from Sewage Water in Naples and Palermo, Italy, in 2011

Human sapoviruses were identified in 15 (12.4 %) of 121 inlet sewage samples collected from wastewater treatment plants in Naples and Palermo, Italy, in 2011. All strains, except one GI.1, were genotyped as GI.2 by sequencing a capsid gene fragment. This is the first detection of sapovirus in wastewaters in Italy.

Pattern of activation of human antigen presenting cells by genotype GII.4 norovirus virus-like particles

Background

Virus-like particles (VLPs) from an Italian GII.4 norovirus strain were used to investigate activation and maturation of circulating antigen presenting cells (APCs) of human origin.

Methods

Peripheral blood mononuclear cells (PBMCs) isolated from five healthy subjects were pulsed ex vivo with VLPs, and stained with a set of monoclonal antibodies (MAbs) for phenotypic analysis by flow cytometry. Cytokine release in cell supernatants was investigated by ELISA.

Results

Norovirus VLPs induced activation and maturation of circulating APCs derived from the five donors, as well as production of IL-6, IFN-γ and TNF-α cytokines.

Conclusions

The present results suggest that VLPs can activate antigen presenting cells for an efficient induction of the adaptive immune response.

Hepatitis E virus in pork production chain in Czech Republic, Italy, and Spain, 2010

Processing does not substantially abate endogenous virus.

We evaluated the prevalence of hepatitis E virus (HEV) in the pork production chain in Czech Republic, Italy, and Spain during 2010. A total of 337 fecal, liver, and meat samples from animals at slaughterhouses were tested for HEV by real-time quantitative PCR. Overall, HEV was higher in Italy (53%) and Spain (39%) than in Czech Republic (7.5%). HEV was detected most frequently in feces in Italy (41%) and Spain (39%) and in liver (5%) and meat (2.5%) in Czech Republic. Of 313 sausages sampled at processing and point of sale, HEV was detected only in Spain (6%). HEV sequencing confirmed only g3 HEV strains. Indicator virus (porcine adenovirus) was ubiquitous in fecal samples and absent in liver samples and was detected in 1 slaughterhouse meat sample. At point of sale, we found porcine adenovirus in sausages (1%–2%). The possible dissemination of HEV and other fecal viruses through pork production demands containment measures.

Prevalence and transmission of hepatitis E virus in domestic swine populations in different European countries

BACKGROUND

Hepatitis E virus (HEV) genotype 3 and 4 can cause liver disease in human and has its main reservoir in pigs. HEV investigations in pigs worldwide have been performed but there is still a lack of information on the infection dynamics in pig populations.

FINDINGS

The HEV transmission dynamics in commercial pig farms in six different European countries was studied. The data collected show prevalence in weaners ranging from 8% to 30%. The average HEV prevalence in growers was between 20% and 44%. The fatteners prevalence ranged between 8% and 73%. Sows prevalence was similar in all countries. Boar faeces were tested for HEV only in Spain and Czech Republic, and the prevalence was 4.3% and 3.5% respectively. The collected data sets were analyzed using a recently developed model to estimate the transmission dynamics of HEV in the different countries confirming that HEV is endemic in pig farms.

CONCLUSIONS

This study has been performed using similar detection methods (real time RT-PCR) for all samples and the same model (SIR model) to analyse the data. Furthermore, it describes HEV prevalence and within-herd transmission dynamics in European Countries (EU): Czech Republic, Italy, Portugal, Spain, The Netherlands and United Kingdom, confirming that HEV is circulating in pig farms from weaners to fatteners and that the reproductive number mathematical defined as R0 is in the same range for all countries studied.

Viral and antibody HEV prevalence in swine at slaughterhouse in Italy

Hepatitis E is an acute disease of humans caused by a small RNA virus, Hepatitis E virus (HEV). In recent years, an increasing number of autochthonous human infections have been reported in industrialized countries. Genotype 3 is the main HEV type circulating in swine, and is also reported in sporadic cases of hepatitis E in humans worldwide. To date one serotype has been described. We have conducted a survey to detect antibodies against HEV in 48 swine at a slaughterhouse in Northern Italy, using ELISA test. Mean seroprevalence in the studied animal group was 87.0%. Bile, liver and feces from the 48 animals were also collected, and HEV RNA was detected by nested reverse transcription-polymerase chain reaction, amplifying a fragment of the ORF2. HEV genome was most frequently detected in bile samples (51.1%), followed by feces (33.3%) and liver (20.8%). Thirty-one out of 48 studied pigs (64.6%) were positive for HEV RNA in at least one sample. Overall, HEV RNA was found at a statistically higher rate in the 3-4-month-old than in 9-10-month-old animals (95.0% vs. 42.9%). Genetic characterization of swine strains identified was performed by sequencing and database alignment. Phylogenetic analysis on the nucleotide sequences from 14 positive PCR products indicated that all strains belonged to genotype 3, clustering in two branches subtypes g3c and g3f.