Hepatitis E virus (HEV) is an important cause of acute viral hepatitis in humans worldwide. The food-borne transmission of HEV appears to be a major route in Europe through the consumption of pork and wild boar meat. HEV epidemiology in wild boars has been investigated mainly in Northern and Central Italian regions, whilst information from Southern Italy is limited. We investigated the occurrence of HEV in wild boar in the Apulia and Basilicata regions (Southern Italy). Thirteen (10.4%) out of one hundred and twenty-five wild boar samples tested positive for HEV using a quantitative reverse transcription PCR. HEV prevalence was 12% in Apulia and 9.3% in Basilicata. Seven samples were genotyped, and different subtypes (c, f, m) of genotype 3 were identified. The complete genome of a 3m strain was determined, and the virus showed the highest nucleotide identity to a human HEV strain identified in France in 2017. These findings demonstrate the substantial circulation of HEV in the wild boar population in Italian Southern regions. Gathering information on the HEV strains circulating in different geographical areas is useful for tracking the origin of HEV outbreaks and assessing the epidemiological role of wild boar as a potential virus reservoir for domestic pigs.

Colistin is a last-resort drug for the treatment of infections by carbapenem-resistant Enterobacteriaceae, and the emergence of colistin resistance poses a serious clinical challenge. The aim of this study was to investigate the occurrence of colistin-resistant Escherichia coli in retail meat in Southern Italy in 2018–2020. Of 570 samples, 147 contained E. coli. Two out of 147 (1.4%) E. coli showed a non-wild-type phenotype to colistin and harboured mcr-1. mcr-1 was also detected in a wild-type isolate, resulting in a 2% mcr prevalence. mcr-1-positive isolates originated from turkey meat collected in Apulia (n = 2) and Basilicata (n = 1). A whole-genome sequencing analysis confirmed mcr-1.2 and mcr-1.1 in two and one isolate, respectively. The strains were diverse, belonging to three multi-locus sequence types (ST354, ST410, SLV of ST10) and harbouring genes mediating resistance to antimicrobials in two, six and seven classes. mcr-1 was carried by IncX4 plasmids with high nucleotide similarity to IncX4 plasmids harbouring mcr-1.2 and mcr-1.1 in Enterobacterales from different sources and geographical regions. This is the first study reporting updates on E. coli non-wild-type to colistin from retail meat in Southern Italy, highlighting the importance of phenotypic and genotypic antimicrobial resistance surveillance to contain the dissemination of mcr among E. coli.

Hepatitis E virus (HEV) represents one of the principal causative agents of hepatitis globally. Among the five HEV genotypes affecting humans, genotypes 3 and 4 are zoonotic and are the main source of hepatitis E in developed countries. HEV has been detected in several foods. The present work investigated the presence of this virus in shellfish sold at retail in the Apulia region of Italy. The presence of HEV RNA was assessed by real-time RT-PCR in 225 shellfish samples collected during 2018. Overall, two (0.89%) of these samples tested positive for HEV RNA. To our knowledge, this is the first notification of the detection of HEV in mussels sold at retail in the Apulia region. These data highlight the potential role of shellfish as a vehicle for the transmission of viral pathogens.

Hepatitis E virus (HEV) represents an emerging risk in industrialized countries where the consumption of contaminated food plays a pivotal role. Quantitative real-time RT-PCR (RT-qPCR) is one of the most suitable methods for the detection and quantification of viruses in food. Nevertheless, quantification using RT-qPCR has limitations. Droplet digital PCR (ddPCR) provides the precise quantification of nucleic acids without the need for a standard curve and a reduction in the effect on virus quantification due to the presence of inhibitors. The objectives of the present work were (i) to develop a method for the absolute quantification of HEV in swine tissues based on ddPCR technology and provide internal process control for recovery assessment and (ii) to evaluate the performance of the method by analyzing a selection of naturally contaminated wild boar muscle samples previously tested using RT-qPCR. The method was optimized using a set of in vitro synthesized HEV RNA and quantified dsDNA. The limit of detection of the developed ddPCR assay was 0.34 genome copies/µL. The analysis of the wild boar samples confirmed the validity of the ddPCR assay. The duplex ddPCR method showed no reduction in efficiency compared to individual assays. The method developed in the present study could represent a sensitive assay for the detection and absolute quantification of HEV RNA in food samples with the advantage of presenting the co-amplification of internal process control.

Antimicrobial resistance (AMR) is recognised as a major global public health threat, with the environment increasingly acknowledged as a key reservoir and dissemination pathway for resistant bacteria and resistance genes. In this study, 148 surface water samples were collected between 2023 and 2024 from six rivers and three canals discharging wastewater into two lake waters in Southern Italy to assess the occurrence and genomic features of extended-spectrum β-lactamase (ESBL)-, AmpC-, and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae. Relevant isolates were obtained using selective culturing, and tested for antimicrobial susceptibility by broth microdilution. Major β-lactam resistance genes were detected by real-time PCR. Whole-genome sequencing (WGS) was performed on presumptive carbapenemase-producing isolates. ESBL- and/or carbapenemase-producing Enterobacterales were detected in 67.6% of samples, yielding a total of 176 non-duplicate isolates. The most prevalent gene was bla_CTX-M, detected in 79.3% of positive isolates (96/121), while carbapenemase genes were detected in 20.6% (25/121) of isolates, mainly bla_OXA-48 and bla_VIM. WGS analysis of carbapenemase PCR-positive isolates revealed occurrence of clinically relevant high-risk clones, such as K. pneumoniae ST512/ST307 carrying bla_KPC-3 and E. coli ST10 harbouring bla_OXA-244. These findings highlight a potential risk to public health and underscore the importance of integrating environmental compartments into One Health surveillance frameworks for AMR.

The illegal treatment of tuna with nitrite is a significant food safety concern. The risk may be due to not only the high nitrite levels and the possible formation of N-Nitrosamines but also to the possible increase in biogenic amines and microbial load and also pathogens. This study optimized the treatment of red tuna (Thunnus thynnus) with nitrite solutions and then determined several chemical (histamine, total volatile basic nitrogen (TVBN), biogenic amines, nitrite/nitrate, ascorbic acid, and sulfites) and microbiological (total microbial count, Enterobacteriaceae, Vibrionaceae, coagulase-positive staphylococci, Salmonella, Escherichia coli) parameters, comparing the results obtained with fresh samples with those obtained with treated samples after 5 days of storage (4 °C). The effect of such treatment on samples voluntarily contaminated with some pathogens was also investigated. The results indicate that if the products are characterized by suitable hygienic quality, the total microbial load and the levels of histamine and TVBN after 5 days of storage are below the legal limits, and no health risk subsists. The growth of pathogens/histaminogens (Salmonella and Morganella morganii) was also substantially inhibited during storage. Thus, this work confirmed that the high nitrite amounts and the possible development of N-nitrosamines represent the only significant food safety concerns.