Control of Raw Pork Liver Sausage Production Can Reduce the Prevalence of HEV Infection.

After an acute hepatitis E (HEV) outbreak in Southern Switzerland, in January 2017 the local public health authorities started an active program of food chain control and public education. In this retrospective study, we analysed all laboratory-confirmed acute cases of HEV infection diagnosed between 2014 and 2020. In the period before the public health intervention, the number of cases increased steadily from 2014 (4 of 40 tests, 10%) reaching a peak in the last quarter of 2016 (42 of 285 tests, 14.7 %). Afterwards, the number of positive cases decreased steadily, reaching its lowest value (0.3%) in the second quarter of 2019. There was a statistically significant difference between the frequency of positive cases and period of testing, i.e., before and after the introduction of the public health interventions. Our study shows that active public health measures to control sausages containing raw pork liver can reduce the prevalence of HEV infection.

Detection of Hepatitis E Virus RNA in Raw Cured Sausages and Raw Cured Sausages Containing Pig Liver at Retail Stores in Switzerland.

Hepatitis E virus (HEV) is the causative agent of an acute and self-limiting hepatitis and is increasingly detected in food products containing pork. In this study, 102 raw sausages containing pig liver (mortadella di fegato) and 18 raw pork sausages (salami type sausage) collected at retail level in a region of southern Switzerland were screened for the presence of HEV by quantitative real-time reverse transcription PCR. HEV was detected in 12 (11.8%) of 102 mortadella di fegato products but not in any of the salami sausages. Viral loads in the mortadella di fegato sausages ranged from log HEV 2.3 to 5.7 genome copies per gram of food product. This study identifies mortadella di fegato type sausages made with raw pig liver as a potential source of HEV infection in humans.

Complete Genome Sequences of Two Swiss Hepatitis E Virus Isolates from Human Stool and Raw Pork Sausage.

We present here the full-length genome sequences of two hepatitis E virus genotype 3 (HEV-3) isolates from a human stool sample from a patient with acute hepatitis and a raw sausage containing pig liver. Sequence analysis implies that Swiss HEV isolates may form a novel subgroup of HEV-3 viruses.

Local Outbreak of Listeria monocytogenes Serotype 4b Sequence Type 6 Due to Contaminated Meat Pâté.

In January and February 2016, five cases of confirmed and two cases of probable infection due to Listeria monocytogenes serotype 4b, sequence type (ST) 6 belonging to a single pulsed-field gel electrophoresis pulsotype pattern were registered in a region of southern Switzerland. L. monocytogenes was detected in blood samples (four cases) and pleural fluid (one case). Furthermore, L. monocytogenes 4b ST6 was detected in a stool sample of an asymptomatic person exposed to a common food. Forthwith, the food safety authority and a local gourmet meat producer reported L. monocytogenes contamination of meat pâté. Analysis of further food and environmental samples from the premises of the producer yielded isolates matching the clinical strains and confirmed the presence of L. monocytogenes 4b ST6 in the mincing machine as the cause of the food contamination.

Further evidence for staphylococcal food poisoning outbreaks caused by egc-encoded enterotoxins.

Staphylococcal food poisoning represents the most prevalent foodborne intoxication worldwide. It is caused by oral intake of enterotoxins preformed by Staphylococcus aureus in food. The relevance of newly described enterotoxins in outbreaks of staphylococcal food poisoning is controversially discussed. Although the staphylococcal enterotoxins SEG, SEI, SEM, SEN, and SEO elicit emesis in a monkey feeding assay, there has been no conclusive proof of their emetic activity in humans. In this study, we provide further evidence suggesting that one of these enterotoxins or a combination of SEG, SEI, SEM, SEN, and SEO cause staphylococcal food poisoning. We investigated two outbreaks registered with the Swiss Federal Office of Public Health, in which only Staphylococcus aureus strains harboring the egc cluster, including seg, sei, sem, sen, and seo linked to typical signs of staphylococcal food poisoning were isolated. The outbreaks were caused by consumption of raw goat cheese and semi-hard goat cheese, and were linked to strains assigned to CC45 (agr type I) and CC9 (agr type II), respectively. These outbreaks provide further evidence that newly-described staphylococcal enterotoxins are likely to cause staphylococcal food poisoning in humans.

DNA methylation patterns at the IGF2-H19 locus in sperm of Swiss Landrace and Swiss Large White boars.

DNA methylation patterns at the IGF2-H19 locus were investigated in sperm DNA from Swiss Landrace (SL) and Swiss Large White (LW) boars. The putative IGF2 differentially methylated regions (DMR) 0, 1 and 2, a quantitative trait nucleotide (QTN) region in the intron 3 and a CpG island in the intron 4 of the IGF2 gene as well as three regions around porcine CTCF binding sites within the H19 differentially methylated domain (DMD) were selected for the DNA methylation analysis. In both breeds putative IGF2 DMR0, 1, 2 and H19 DMD were hypermethylated. Significant differences in DNA methylation content were found between the two breeds in the two DMD regions proximal to the H19 gene. The IGF2 QTN region and the CpG island in the IGF2 intron 4 were hypomethylated in sperm DNA of both breeds. The methylation analysis revealed significantly more methylated CpG sites in the intron 4 of sperm from the LW breed than in that from SL. No difference was found in global DNA methylation between the two breeds. These results indicate differences in DNA methylation patterns between breeds and it remains to be established whether variation in DNA methylation patterns impacts on phenotypic traits.

Nitric oxide directly inhibits ghrelin-activated neurons of the arcuate nucleus.

The hypothalamic arcuate nucleus (Arc) is a target site for signals regulating energy homeostasis. The orexigenic hormone ghrelin directly activates neurons of the medial arcuate nucleus (ArcM) in rats. Nitric oxide (NO) is a neuromodulator implicated in the control of food intake and body weight. NO is produced by nitric oxide synthase (NOS) and induces the formation of cyclic guanosine monophosphate (cGMP) via a stimulation of soluble guanylate cyclase (sGC). Both enzymes NOS and sGC have been identified in the Arc. Using extracellular recordings we characterized the effects of NO signaling on ArcM neurons and their co-sensitivity to ghrelin. The artificial NO donor sodium nitroprusside (10(-4) M) reversibly inhibited 91% of all ArcM neurons by a direct postsynaptic mechanism. 52% of ArcM neurons were excited by ghrelin. In all but one of these neurons SNP caused inhibitory responses. The SNP-induced inhibitions were mediated by cGMP since they were blocked by the specific sGC inhibitor ODQ (1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one, 10(-4) M). Furthermore, the membrane permeating cGMP analogue 8-Br-cGMP (10(-4) M) mimicked the inhibitory responses of SNP. In immunohistological in vitro studies SNP induced a cGMP formation, which could also be blocked by ODQ. The current studies demonstrate that NO/cGMP signaling inhibits a large population of ArcM neurons including ghrelin-excited cells. Since an activation of the latter neurons is regarded as a correlate of negative energy balance, NO may represent an anorectic neuromodulator in the Arc and/or restrain the action of signals promoting energy intake. NO signaling in the Arc is also induced following inflammation suggesting a possible role of Arc-intrinsic NO in disease-related anorexia.