ABSTRACT
The aim of the present study was to investigate the effect of short purification cycles on the safety of naturally contaminated Mytilus galloprovincialis from harvesting areas of the Gulf of Olbia (Sardinia, Italy). Samples from ten batches of mussels were collected before, during and after purification treatment at two purification centres (A-B). All the samples were analysed for Escherichia coli and Salmonella spp according to Council Regulation (EC) 2285/2015. Detection and enumeration of Vibrio spp were performed according to previously published methods. Presumptive identification of Vibrio spp isolates were performed by means of conventional biochemical tests and polymerase chain reaction. The presence of Hepatitis A virus was detected by nested reverse transcriptase-polymerase chain reaction. Environmental parameters (water temperature and salinity) were also recorded. The results of Escherichia coli counts showed the overall efficacy of the short purification cycles; a purification cycle of 8â¯h led to a rapid decline in the concentration. The decrease in Escherichia coli counts does not correlate with the presence of naturally occurring vibrios, the decline of which occurs at an even slower rate. The average contamination levels for Vibrio spp before purification were 8.20⯱â¯0.47 and 7.99⯱â¯0.62 Log10â¯CFU/g in samples collected at purification plants A and B, respectively. After purification, the average contamination levels were 8.10⯱â¯0.60 Log10â¯CFU/g at purification plant A and 7.85⯱â¯0.57 Log10â¯CFU/g at purification plant B. The contaminated samples revealed the presence of Vibrio alginolyticus (n=21), Vibrio fluvialis (n=12), Vibrio cholerae (n=4), Vibrio parahaemolyticus (n=2) and Vibrio vulnificus (n=1). The Vibrio parahaemolyticus isolates carried the tdh or the trh genes. None of the isolates was tdh+/trh+. Salmonella spp and Hepatitis A virus were not detected. The adoption of short purification cycles for Mytilus galloprovincialis in the presence of pathogenic vibrios might not be sufficient to guarantee the safety of consumers.
Subject(s)
Food Contamination , Mytilus/microbiology , Seafood/microbiology , Shellfish/microbiology , Animals , Escherichia coli/genetics , Escherichia coli/isolation & purification , Food Microbiology , Hepatitis A virus/genetics , Hepatitis A virus/isolation & purification , Italy , Polymerase Chain Reaction/methods , Salinity , Salmonella/genetics , Salmonella/isolation & purification , Temperature , Vibrio/classification , Vibrio/genetics , Vibrio/isolation & purification , Virulence/geneticsABSTRACT
This study was conducted to acquire knowledge on the epidemiology and ecology of some zoonotic agents in snails. Chemical and microbiological analysis was carried out on 46 samples of snails belonging to the species of Helix aspersa and Helix (Eobania) vermiculata. The association between heavy metals and wild snails, a native consumer product in the Region of Sardinia, was determined. The molecular characterisation of Listeria monocytogenes virulence genes has shown a genetic profile that deserves more attention for the improvement of surveillance and risk prevention. Specimens of H. vermiculata showed higher concentrations of cadmium (M=0.80±0.56 mg/kg) than H. aspersa (M=0.61±0.17 mg /kg). A further objective was to determine whether the samples showed significant differences from the point of view of secretion characterisation, in terms of protein content, and to identify species-specific correlations and possible relationships with the environment. The presence of Salmonella enterica sub.sp houtenae (6,14: z4, z23) and Salmonella enterica subsp diarizonae (47: k: e, n, z15) (1 sample), Listeria monocytogenes (2 samples) with Molecular characterization of virulence genes together with the measurement of heavy metals in samples of wild snails has shown a health and hygiene profile that would deserve greater attention for the improvement of the surveillance and prevention of microbiological and chemical risk in such products which currently show a tendency towards increase in consumption.
ABSTRACT
INTRODUCTION: We describe an outbreak of hepatitis A among men who have sex with men (MSM) which evolved in Sassari (Italy), between January 2017 and December 2018, close to a contextual of large concurrent hepatitis A outbreak reported in Europe and recently, in Italy. METHODOLOGY: HAV RNA detection and molecular characterization was performed from serum samples and/or stool by RT - PCR of VP1/2A junction region that ranges from nt. 2,873 to nt. 3,376. The phylogenetic correlation of the circulating hepatitis A strains was assessed by sequencing method according to the HAVNET protocol. RESULTS: 10 Acute Hepatitis A virus (AHA)-positive cases, 8 of which were among men who have sex with men (MSM) were identified. All patients were tested at the time of hospitalization for the presence of anti-HIV antibodies, only two MSM resulted co-infected by HIV. No differences were observed in median age (37 years vs. 41 years, P-value = 0.14), severity or duration of hospitalization between seropositive and HIV-negative men. Phylogenetic analysis was conducted in 2 cases and revealed two distinct sequences of genotype IA linking to clusters recognized in MSM in other European countries in 2016. CONCLUSION: Our study reported a recent increase of notified hepatitis A cases attributable to cases in the European interconnectedness of MSM in Sassari, a small locality. Hepatitis A vaccination for MSM in Sardinia region is recommended; however, our data emphasize the need of hepatitis A screening and vaccination not only for MSM with occasional partners but also for those in monogamous relationships.
Subject(s)
Disease Outbreaks , Hepatitis A virus/classification , Hepatitis A/epidemiology , Sexual and Gender Minorities , Adult , Coinfection , HIV Infections , Hepatitis A virus/genetics , Hepatitis A virus/isolation & purification , Homosexuality, Male , Hospitalization , Humans , Italy/epidemiology , Male , Molecular Diagnostic Techniques , Phylogeny , RNA, Viral , Reverse Transcriptase Polymerase Chain Reaction , Risk Factors , Serologic TestsABSTRACT
Edible lamellibranch molluscs can be involved in foodborne disease and infections of varying severity. They are filter feeding animals able to retain and concentrate in their organism bacteria, parasites, viruses and biotoxins marine algae present in their external environment. Major shellfish harvesting and relaying areas from different areas in Sardinia region were defined and studied by analysing different physicochemical parameters in the water and the levels of Escherichia coli (E. coli), Norovirus (NoVs) genogroup I (NoVGI), NoVs genogroup II (NoVGII) and hepatitis A virus (HAV) in the shellfish harvested and farmed from 2009 to 2011. During that period the identification of the viral agents was carried out by one step real-time reverse transcriptase-polymerase chain reaction and Escherichia coli according to ISO TS 16649-3:2005 standard method. A total of 1266 shellfish samples were tested for NoVGI, NoVGII, HAV and faecal indicators. Norovirus contamination was found in 337 samples (26.6%); only one sample of mussels was positive for HAV (0.08%); while E. coli prevalence was 3.8% in shellfish. The probability of observing shellfish samples positive for NoVs, HAV and E. coli presence was associated with harvesting, growing and relaying areas, period of sampling, environmental parameters, animal species (P<0.05). Although the higher prevalence rate of human enteropathogenic viruses was found in the winter period, we did not observe a significant relationship between the effect of seawater temperature (seasonality) and NoVs presence all over the study period; in fact, according to statistical analysis, the presence of human enteric viruses does not appear to be related to water temperature.
ABSTRACT
With this study, 28 pools of snails of the genus Helix, respectively Helix aspersa (n=24) and Helix vermiculata (n=4) were analysed. They were taken from snail farming and stores. The snails were from Sardinia, other regions of Italy, and from abroad. All the samples were examined as pool looking for these microbiological target: Salmonella spp., Listeria monocytogenes, Escherichia coli O157, Clostridium perfringens, Norovirus and Hepatitis A Virus (HAV). In the same pools, the concentration of cadmium and lead by inductively coupled plasma mass spectrometry was also determined. The levels of these heavy metals were quite high, especially for cadmium. Two samples were positive for Salmonella spp., while no sample was positive for Escherichia coli O157, HAV and Norovirus. Two samples were positive for Clostridium perfringens and 8 for Listeria monocytogenes. The microrganisms related to Listeria monocytogenes were identified using biochemical techniques, then serotyped and gene sequenced by multiple loci sequence typing technique. Furthermore, antimicrobial restistence was tested on the same samples.
ABSTRACT
In accordance with European Union regulations, from 5 February until 15 December 2008, sampling and analysis activities were conducted in Italy to assess the extent of contamination caused by thermotolerant Campylobacter in broiler chickens farmed nationwide. The survey involved 48 poultry slaughterhouses distributed across eleven regions of Italy, where the caeca and carcasses of 393 slaughter batches were sampled. A total of 284 batches (72.3%) gave positive results for Campylobacter spp. as follows: 52.1% were contaminated by C. jejuni, 55.6% by C. coli and 1.1% by C. lari. C. jejuni and C. coli were isolated together in 37 batches (13% of positive results). Campylobacter spp. was isolated only from the caeca in 251 slaughter batches (63.9%) including caecal isolates of C. jejuni (48.2%), C. coli (50.6%), and C. lari (1.2%). Carcasses from 182 batches (46.3%) were contaminated by C. jejuni in 40.7% of cases, C. coli in 57.7% and the absence of C. lari from all batches examined. The contamination level observed in the carcasses ranged between 10 and 1.6 × 10(7) cfu/g.