Ten different viral agents infecting and co-infecting children with acute gastroenteritis in Southern Italy: Role of known pathogens and emerging viruses during and after COVID-19 pandemic.

Acute gastroenteritis (AGE) represents a world public health relevant problem especially in children. Enteric viruses are the pathogens mainly involved in the episodes of AGE, causing about 70.00% of the cases. Apart from well-known rotavirus (RVA), adenovirus (AdV) and norovirus (NoV), there are various emerging viral pathogens potentially associated with AGE episodes. In this study, the presence of ten different enteric viruses was investigated in 152 fecal samples collected from children hospitalized for gastroenteritis. Real time PCR results showed that 49.3% of them were positive for viral detection with the following prevalence: norovirus GII 19.7%, AdV 15.8%, RVA 10.5%, human parechovirus (HPeV) 5.3%, enterovirus (EV) 3.3%, sapovirus (SaV) 2.6%. Salivirus (SalV), norovirus GI and astrovirus (AstV) 1.3% each, aichivirus (AiV) found in only one patient. In 38.2% of feces only one virus was detected, while co-infections were identified in 11.8% of the cases. Among young patients, 105 were ≤5 years old and 56.0% tested positive for viral detection, while 47 were >5 years old with 40.0% of them infected. Results obtained confirm a complex plethora of viruses potentially implicated in gastroenteritis in children, with some of them previously known for other etiologies but detectable in fecal samples. Subsequent studies should investigate the role of these viruses in causing gastroenteritis and explore the possibility that other symptoms may be ascribed to multiple infections.

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.

Persistent Infection with Rotavirus Vaccine Strain in Severe Combined Immunodeficiency (SCID) Child: Is Rotavirus Vaccination in SCID Children a Janus Face?

We report the first case, to our knowledge, in Italy, of a severe combined immunodeficiency patient with a persistent rotavirus infection due to a vaccine derived strain. Rotavirus was detected by enzyme immunoassays and RT-PCR in stool specimens for five months. The persistent infection was resolved after complete immune reconstitution achieved by hematopoietic stem cell transplantation. This case underlines the importance of neonatal SCID_screening.

Detection and molecular characterization of enteric viruses in children with acute gastroenteritis in Northern Italy.

Enteric viral infections are a major concern for public health, and viral acute gastroenteritis is the principal cause of pediatric morbidity and mortality worldwide, mostly in developing countries. The purpose of this study was to determine the prevalence of different enteric viruses detected in a pediatric population with acute gastroenteritis symptoms, and to characterize the strains detected. Stools were collected from children, aged from 2 months to 15 years old, admitted to one of the main hospitals of Northern Italy, between November 2015 and October 2016. Stools were tested for nine enteric viruses (adenovirus, rotavirus A, norovirus, astrovirus, sapovirus, enterovirus, parechovirus, bocavirus and aichivirus) by molecular methods. Furthermore, rotavirus, norovirus and adenovirus were deeply characterized by nucleotide sequencing and phylogenetic analysis. A total of 151 out of 510 (29.6%) stools analyzed resulted positive for at least one of the enteric virus investigated. The most common virus detected was rotavirus A (53/151, 35.1%), followed by norovirus (39/151, 25.8%), adenovirus (35/151, 23.1%), sapovirus (9/151, 6%), enterovirus (5/151, 3.3%), astrovirus (5/151, 3.3%), parechovirus (4/151, 2.6%) and bocavirus (1/151, 0.6%). Aichi virus was not detected in any sample. Co-infections were detected in 12 out of 510 faecal samples (2.3%). These data improved the knowledge of the enteric viruses circulating in children in Northern Italy. In fact, besides rotavirus, adenovirus and norovirus, several viruses circulated across the whole year in the pediatric population object of this study. The introduction of specific viral diagnosis in our clinical setting will improve patient care by reducing unnecessary use of antibiotics addressing the right etiologic diagnosis.

Detection of uncommon G3P[3] rotavirus A (RVA) strain in rat possessing a human RVA-like VP6 and a novel NSP2 genotype.

Rotavirus is one of the leading causes of acute gastroenteritis in infants and young children. RVAs infect not only humans but also a wide range of mammals including rats, which represent a reservoir of several other zoonotic pathogens. Due to the segmented nature of the RVA genome, animal RVA strains can easily adapt to the human host by reassortment with co-infecting human viruses. This study aims to detect and characterize RVA in the intestinal content of Italian sinantropic rats (Rattus rattus). Out of 40 samples examined following molecular approach, one resulted positive for RVA. The molecular characterization of VP1-4, 6 and 7, and NSP1-5 genes by sequencing revealed the genomic constellation G3-P[3]-I1-R11-C11-M10-A22-N18-T14-E18-H13. This uncommon genomic combination includes: the VP1-4,VP7, the NSP1, 3, 4 and 5 gene segments, closely related to those of RVA from rodents, the N18 novel genotype established for the NSP2 gene segment and the human Wa-like VP6 gene, suggesting interspecies reassortment.

Hospital-acquired rotavirus and norovirus acute gastroenteritis in a pediatric unit, in 2014-2015.

The occurrence of hospital-acquired acute gastroenteritis (AGE) is a major concern for public health. RotavirusA (RVA) and norovirus (NoV) are common causes of viral AGE in the pediatric population, and their role in nosocomial infections has been proven, remaining poorly investigated. To investigate RVA and NoV in hospital-acquired AGE, 55 stool samples from children with nosocomial AGE were collected between May 2014 and May 2015. To evaluate virus spreading routes, 51 environmental swabs were collected from staff and patients' rooms. Stools were tested for both RVA and NoV RNA by reverse-transcription-PCR. Nucleotide sequencing and phylogenetic analysis were performed to characterize the viruses. Forty-seven of 55 cases analyzed resulted positive for RVA. The predominant genotype was G4P[8] (18/55) followed by G1P[8] (14/55). Mixed RVA infections were also detected (7/55). Twenty-two samples were positive for NoV, and GII.4 was revealed to be the predominant genotype. Seventeen samples were positive for both RVA and NoV. This study aimed to evaluate the burden of norovirus and rotavirus nosocomial AGE, contributing to identify the environment source of infections and to activate effective strategies for intervention. The reduction in nosocomial AGE cases is an important aspect, considered the worsened disease course in transplant, cancer, and intensive care unit inpatients.