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Abstract Bacterial species often comprise well-separated lineages, likely emerged and maintained by genetic isolation and/or ecological divergence. How these two evolutionary actors interact in the shaping of bacterial population structure is currently not fully understood. In this study, we investigate the genetic and ecological drivers underlying the evolution of Serratia marcescens, an opportunistic pathogen with high genomic flexibility and able to colonise diverse environments. Comparative genomic analyses reveal a population structure composed of five deeply-demarcated genetic clusters with open pan-genome but limited inter-cluster gene flow, partially explained by Restriction-Modification (R-M) systems incompatibility. Furthermore, a large-scale research on hundred-thousands metagenomic datasets reveals only a partial habitat separation of the clusters. Globally, two clusters only show a separate gene composition coherent with ecological adaptations. These results suggest that genetic isolation has preceded ecological adaptations in the shaping of the species diversity, an evolutionary scenario coherent with the Evolutionary Extended Synthesis.

Ralstonia spp. are low-virulent environmental Gram-negative bacteria that can cause serious nosocomial infections in immunocompromised patients. We report the characteristics of a cluster of R. insidiosa bacteremia cases occurring in our oncology day ward in Milan, Italy, between January and March 2022. A case was defined as a cancer patient attending our day ward and whose blood culture (performed because of bacteremia symptoms) led to the isolation of Ralstonia insidiosa. An epidemiological investigation was conducted in order to seek the possible source of infection. Seven adult patients received curative or palliative treatment via infusion through a Port-a-Cath (PAC). All developed symptoms within 24 h of the infusion (three during the infusion itself). Ralstonia insidiosa was isolated in the blood drawn from the PAC in all patients. All of the isolates were susceptible to carbapenems, fluoroquinolones, and piperacillin/tazobactam but resistant to aminoglycosides and cephalosporins. Systemic and/or lock antibiotic therapy led to stable symptom resolution and negative blood cultures in five patients, whereas bacteremia recurred in two patients. An epidemiological investigation suggested that extrinsic contamination of antiseptic solutions was the possible cause of the R. insidiosa infections. Although R. insidiosa is not considered a virulent pathogen, clinicians, microbiologists, and infection control teams should be aware about its potential to cause outbreaks of nosocomial bloodstream infections, especially in immunocompromised patients bearing central venous catheters.

Bacterial infections pose significant global health challenges, often underestimated due to difficulties in accurate diagnosis, especially when culture-based diagnostics fail. This study assesses the effectiveness of 16S-based metagenomic next generation sequencing (NGS) for identifying pathogens in culture-negative clinical samples across various medical settings. Overall, 48% of samples were collected from orthopedics, 15% from neurosurgery, and 12% in cardiac surgery, among others. The detection rate of monomicrobial infections was 68.6%, and 5.7% for polymicrobial infections. In addition, NGS detected bacteria in all samples from the lungs, head and neck, and eye specimens. Cutibacterium acnes (11%, 12/105) was the most frequent microorganism, followed by Staphylococcus epidermidis (10.4%, 11/105), and Staphylococcus aureus (9.5%, 10/105). In conclusion, 16S-targeted metagenomic sequencing enhances pathogen detection capabilities, particularly in instances where traditional cultures fail. By the combination of NGS and bacterial cultures, microbiologists might provide a more accurate diagnosis, guiding more effective treatments and potentially reducing healthcare costs associated with empirical treatments.

Summary: Serratia marcescens is an opportunistic pathogen that survives in inhospitable environments causing large outbreaks, particularly in neonatal intensive care units (NICUs). Genomic studies revealed that most S. marcescens nosocomial infections are caused by a specific clone (here “Infectious clone”). Whole genome sequencing (WGS) is the only portable method able to identify this clone, but it requires days to obtain results. We present a cultivation-free hypervariable-locus melting typing (HLMT) protocol for the fast detection and typing of S. marcescens, with 100% detection capability on mixed samples and a limit of detection that can reach the 10 genome copies. The protocol was able to identify the S. marcescens infectious clone with 97% specificity and 96% sensitivity when compared to WGS, yielding typing results portable among laboratories. The protocol is a cost and time saving method for S. marcescens detection and typing for large environmental/clinical surveillance screenings, also in low-middle income countries.

Abstract Adjuvant chemotherapy recommendations for ER+/HER2− early-stage breast cancers (eBC) involve integrating prognostic and predictive information which rely on physician judgment; this can lead to discordant recommendations. In this study we aim to evaluate whether Oncotype DX improves confidence and agreement among oncologists in adjuvant chemotherapy recommendations. We randomly select 30 patients with ER+/HER2− eBC and recurrence score (RS) available from an institutional database. We ask 16 breast oncologists with varying years of clinical practice in Italy and the US to provide recommendation for the addition of chemotherapy to endocrine therapy and their degree of confidence in the recommendation twice; first, based on clinicopathologic features only (pre-RS), and then with RS result (post-RS). Pre-RS, the average rate of chemotherapy recommendation is 50.8% and is higher among junior (62% vs 44%; p

Staphylococcus aureus bacteraemia (SAB) is a life-threatening bloodstream infection. Improved adherence to quality-of-care indicators (QCIs) can significantly enhance patient outcomes. This quasi-experimental study evaluated the impact of a bundle of interventions on QCI adherence in adult patients with SAB. Additionally, a molecular rapid diagnostic test (mRDT) for S. aureus and methicillin resistance was introduced during weekdays. We compared pre-intervention (January–December 2022) and post-intervention (May 2023–April 2024) data on QCI adherence and time to appropriate treatment. A total of 56 and 40 SAB episodes were included in the pre- and post-intervention periods, respectively. Full QCI adherence significantly increased from 28.6% to 67.5% in the post-intervention period (p < 0.001). The mRDT diagnosed SAB in eight cases (26.6%), but the time to achieve appropriate target therapy did not improve in the post-intervention period (54 h (IQR 30–74) vs. 72 h (IQR 51–83), p = 0.131). The thirty-day mortality rate was comparable between the two periods (17.9% vs. 12.5%, p = 0.476). This study demonstrates that a bundle of interventions can substantially improve adherence to SAB management QCIs.

Tracing the profile of pediatric Lyme borreliosis (LB) in Europe is difficult due to the interregional variation in its incidence and lack in notifications. Moreover, the identification of LB can be challenging. This study is an 18-year case series of 130 children and adolescents aged under 18 years referred to the Pediatric Infectious Diseases Unit at L. Sacco Hospital, Milan, with suspicion of LB, between January 2005 and July 2023. The routine serological workup consisted of a two-step process: an initial screening test followed by Western blot (WB). Forty-four (34%) patients were diagnosed with LB. The median age was six years, and 45% were females. Of the children with erythema migrans (EM), 33 (57%) were confirmed as having true EM, and, of these, 4 (12%) were atypical. Ten (23%) patients had early disseminated/late diseases, including facial nerve palsy (n = 3), early neuroborreliosis (n = 1), arthritis (n = 3), relapsing fever (n = 2), and borrelial lymphocytoma (n = 1). No asymptomatic infections were documented. Over seventy percent of confirmed LB cases (n = 31/44) recalled a history of tick bites; in this latter group, 19 (61%) were from the area of the Po River valley in Lombardy. Almost half of the children evaluated for LB complained of non-specific symptoms (fatigue, musculoskeletal pain, skin lesions/rash, and persistent headache), but these symptoms were observed in only two patients with confirmed LB. Most LB cases in our study were associated with EM; two-tier testing specificity was high, but we found frequent non-adherence to international recommendations with regard to the timing of serology, application of the two-step algorithm, and antibiotic over-prescription. Most children were initially assessed for a tick bite or a skin lesion suggestive of EM by a family pediatrician, highlighting the importance of improving awareness and knowledge around LB management at the primary healthcare level. Finally, the strengthening of LB surveillance at the national and European levels is necessary.

Lyme borreliosis (LB) is the most common vector-borne zoonotic inflammatory disease in the Northern Hemisphere. In Italy, the first case was diagnosed in 1985 in a woman in Liguria, while the second, in 1986 in Friuli-Venezia Giulia, documenting the infection in northern Italy. Both diagnoses were confirmed by serological assessment by an indirect immunofluorescence (IFI) technique. Borrelia cultivation from both Ixodes ricinus ticks and human lesions in Trieste (Friuli-Venezia Giulia) identified Borrelia afzelii as the prevalent genospecies; nevertheless, Borrelia garinii, Borrelia burgdorferi (sensu stricto), and Borrelia valaisiana (VS116 Group) were also detected, although less frequently. LB was also documented in other Italian regions: in Tuscany (1991), Trentino–Alto Adige (1995–1996), Emilia-Romagna (1998), Abruzzo (1998), and more recently, Lombardy. Nevertheless, data on LB in other Italian regions, especially in southern Italy and islands, are poor. The aim of this study is to document the spread of LB in Italy through the collection of data from LB patients in eight Italian hospitals located in different Italian regions. Diagnostic criteria for LB diagnosis are as follows: i) the presence of erythema migrans (EM) or ii) a clinical picture suggestive of LB, confirmed by serological tests and/or PCR positivity for Borrelia detection. In addition, data also included the place of residence (town and region) and the place where patients became infected. During the observation period, 1,260 cases were gathered from the participating centers. Although different in extent from northern Italy to central/southern Italy, this study shows that LB is widespread throughout Italy.

(Background) The diagnosis and the antimicrobial treatment of orthopedic infection are challenging, especially in cases with culture-negative results. New molecular methods, such as next-generation sequencing (NGS), promise to overcome some limitations of the standard culture, such as the detection of difficult-to-grow bacteria. However, data are scarce regarding the impact of molecular techniques in real-life scenarios. (Methods) We included cases of suspected orthopedic infection treated with surgery from May 2021 to September 2023. We combined traditional cultures with NGS. For NGS, we performed a metagenomic analysis of ribosomal 16s, and we queried dedicated taxonomic libraries to identify the species. To avoid false positive results, we set a cut-off of 1000 counts of the percentage of frequency of reads. (Results) We included 49 patients in our study. Our results show the presence of bacteria in 36/49 (73%) and 29/49 (59%) cases studied with NGS and traditional cultures, respectively. The concordance rate was 61%. Among the 19/49 discordant cases, in 11/19 cases, cultures were negative and NGS positive; in 4/19, cultures were positive and NGS negative; and in the remaining 4/19, different species were detected by traditional cultures and NGS. (Conclusions) Difficult-to-grow microorganisms, such as slow-growing anaerobic bacteria, were better detected by NGS compared to traditional culture in our study. However, more data to distinguish between true pathogens and contaminants are needed. NGS can be an additional tool to be used for the diagnosis of orthopedic infections and the choice of appropriate antimicrobial therapy.

Critically ill COVID-19 patients are at an increased risk of bloodstream infections (BSIs). We performed a retrospective observational single-center study on COVID-19 patients admitted to intensive care unit (ICU) to assess the incidence of BSIs in four consecutive periods: 21 February–31 July 2020 (W1), 1 August 2020–31 January 2021 (W2), 1 February–30 September 2021 (W3) and 1 October 2021 and 30 April 2022 (W4). BSIs that occurred 48 h after ICU admission were included. The crude incidence of BSIs was estimated by means of Poisson distribution normalized to 1000 patient-days. A total of 404 critically ill COVID-19 patients were admitted to ICU, of whom 284 (61%) developed at least one episode of BSI with an overall crude incidence of 87 events every 1000 patient-days (95% CI 77–98) without a significant difference in consecutive epidemic periods (p = 0.357). Gram-positive bacteria were the most frequent etiological agents of BSIs, contributing to 74.6% episodes. A progressive decrease in BSIs due to Enterococcus spp. was observed (W1 57.4%, W2 43.7%, W3 35.7% and W4 32.7%; p = 0.004). The incidence of BSIs remained stable during different epidemic periods. Enterococcus spp. prevalence was significantly reduced, although still accounted for one third of BSIs in more recent epidemic periods.

Abstract Background Infective endocarditis (IE) is associated with high rates of mortality. Prolonged treatments with high-dose intravenous antibiotics often fail to eradicate the infection, frequently leading to high-risk surgical intervention. By providing a mechanism of antibiotic tolerance, which escapes conventional antibiotic susceptibility profiling, microbial biofilm represents a key diagnostic and therapeutic challenge for clinicians. This study aims at assessing a rapid biofilm identification assay and a targeted antimicrobial susceptibility profile of biofilm-growing bacteria in patients with IE, which were unresponsive to antibiotic therapy. Results Staphylococcus aureus was the most common isolate (50%), followed by Enterococcus faecalis (25%) and Streptococcus gallolyticus (25%). All microbial isolates were found to be capable of producing large, structured biofilms in vitro. As expected, antibiotic treatment either administered on the basis of antibiogram or chosen empirically among those considered first-line antibiotics for IE, including ceftriaxone, daptomycin, tigecycline and vancomycin, was not effective at eradicating biofilm-growing bacteria. Conversely, antimicrobial susceptibility profile of biofilm-growing bacteria indicated that teicoplanin, oxacillin and fusidic acid were most effective against S. aureus biofilm, while ampicillin was the most active against S. gallolyticus and E. faecalis biofilm, respectively. Conclusions This study indicates that biofilm-producing bacteria, from surgically treated IE, display a high tolerance to antibiotics, which is undetected by conventional antibiograms. The rapid identification and antimicrobial tolerance profiling of biofilm-growing bacteria in IE can provide key information for both antimicrobial therapy and prevention strategies.

We have devised an artificial intelligence algorithm with machine reinforcement learning (Q-learning) to construct remarkable entangled states with four qubits. This way, the algorithm is able to generate representative states for some of the 49 true SLOCC classes of the four-qubit entanglement states. In particular, it is possible to reach at least one true SLOCC class for each of the nine entanglement families. The quantum circuits synthesized by the algorithm may be useful for the experimental realization of these important classes of entangled states and to draw conclusions about the intrinsic properties of our universe. We introduce a graphical tool called the state-link graph (SLG) to represent the construction of the quality matrix (Q-matrix) used by the algorithm to build a given objective state belonging to the corresponding entanglement class. This allows us to discover the necessary connections between specific entanglement features and the role of certain quantum gates, which the algorithm needs to include in the quantum gate set of actions. The quantum circuits found are optimal by construction with respect to the quantum gate-set chosen. These SLGs make the algorithm simple, intuitive, and a useful resource for the automated construction of entangled states with a low number of qubits.

In the last years, the rapid spread in anthropized ecosystems of pathogens which are resistant to carbapenem antibiotics has raised great concern. In this study, KPC-producing Klebsiella pneumoniae was found in the River Lambro in June 2019, whereas KPC-producing Klebsiella oxytoca and Citrobacter braakii were identified in untreated wastewaters. Susceptibility profiles indicated resistance to imipenem, ertapenem and meropenem. Different carbapenamase genes (blaKPC, blaNDM, blaVIM, blaOXA-48) were also found in the River Lambro, although not associated to living bacteria. The presence of a wide set of carbapenemase genes and resistant pathogens show that river sediments could act as a reservoir of antibiotic resistance potentially threatening human health.

Aim: Methicillin-resistant Staphylococcus aureus remains a leading cause of hospital and community infections. We report a retrospective molecular characterization of S. aureus strains from different settings: hospital workers and patients, and veterinarian surgeons and pets. Materials and Methods: Eighty-nine S. aureus isolates obtained from nasal swabs of 10 patients, 17 health-care workers (HCWs), 9 pets, and 53 veterinarians were genotypically characterized by means of repetitive extragenic palindromic polymerase chain reaction (Rep PCR) and whole-genome sequencing. Results: Thirteen different sequence types (STs) were detected: ST398, ST22, ST8, ST30, ST15, ST5, ST121, ST45, ST10, ST6, ST34, ST97, and ST1. Two new STs differing from ST22 and ST5 for a single multilocus sequence typing gene were also identified. Rep PCR documented a genetic relationship among isolates obtained from 5 veterinarians and 10 HCWs. Conclusion: The large diversity of S. aureus strains detected may reflect a larger epidemiology within the hospital and community, in which companion animals likely act as a reservoir. We identified the circulation of ST5, ST8, ST15, ST22, ST30, ST45, and ST121 both in the hospital and veterinarian environment. Starting from the idea of a unique setting where our population lives, we consider the relationship between community- and hospital-acquired S. aureus.

Abstract Background The emergence of carbapenem-resistant Klebsiella pneumoniae strains is threatening antimicrobial treatment. Methods Sixty-eight carbapenemase-producing K. pneumoniae strains isolated at Luigi Sacco University Hospital-ASST Fatebenefratelli Sacco (Milan, Italy) between 2012 and 2014 were characterised microbiologically and molecularly. They were tested for drug susceptibility and carbapenemase phenotypes, investigated by means of repetitive extra-genic palindromic polymerase chain reaction (REP-PCR), and fully sequenced by means of next-generation sequencing for the in silico analysis of multi-locus sequence typing (MLST), their resistome, virulome and plasmid content, and their core single nucleotide polymorphism (SNP) genotypes. Results All of the samples were resistant to carbapenems, other β-lactams and ciprofloxacin; many were resistant to aminoglycosides and tigecycline; and seven were resistant to colistin. Resistome analysis revealed the presence of blaKPC genes and, less frequently blaSHV, blaTEM, blaCTX-M and blaOXA, which are related to resistance to carbapenem and other β-lactams. Other genes conferring resistance to aminoglycoside, fluoroquinolone, phenicol, sulphonamide, tetracycline, trimethoprim and macrolide-lincosamide-streptogramin were also detected. Genes related to AcrAB-TolC efflux pump-dependent and pump-independent tigecycline resistance mechanisms were investigated, but it was not possible to clearly correlate the genomic features with tigecycline resistance because of the presence of a common mutation in susceptible, intermediate and resistant strains. Concerning colistin resistance, the mgrB gene was disrupted by an IS5-like element, and the mobile mcr-1 and mcr-2 genes were not detected in two cases. The virulome profile revealed type-3 fimbriae and iron uptake system genes, which are important during the colonisation stage in the mammalian host environment. The in silico detected plasmid replicons were classified as IncFIB(pQil), IncFIB(K), ColRNAI, IncX1, IncX3, IncFII(K), IncN, IncL/M(pMU407) and IncFIA(HI1). REP-PCR showed five major clusters, and MLST revealed six different sequence types: 512, 258, 307, 1519, 745 and 101. Core SNP genotyping, which led to four clusters, correlated with the MLST data. Isolates of the same sequencing type often had common genetic traits, but the SNP analysis allowed greater strain tracking and discrimination than either the REP-PCR or MLST analysis. Conclusion Our findings support the importance of implementing bacterial genomics in clinical medicine in order to complement traditional methods and overcome their limited resolution.

Karl Weick, esponente del cognitivismo costruttivista, considera il sensemaking come un insieme di processi cognitivi in continua costruzione, a posteriori, di significati e di senso della realtà in cui viviamo. Il sensemaking è un processo continuo di creazione di senso quotidiano: le persone percepiscono selettivamente le informazioni su sé stessi e sull’ambiente in cui vivono, tali informazioni vengono elaborate cognitivamente attraverso un processo di selezione e ritenzione in memoria delle mappe cognitive costruite. Pertanto il sensemaking costituisce un’appropriata chiave di lettura dei fenomeni comportamentali in cui sono in gioco le rappresentazioni di un problema, soprattutto quando è di estrema necessità trovare punti di contatto in merito ai rapporti causali tra gli elementi che costituiscono le diverse mappe cognitive degli individui che ne prendono parte. L’analisi delle mappe cognitive può essere utile soprattutto al fine di individuare e condividere con maggiore chiarezza quali potrebbero essere le strade per un corretto ed efficace intervento risolutivo o di trattamento del problema. Dare senso alla malattia significa, sia per il medico che per il paziente, organizzare una mappa cognitiva (connessioni causali di elementi di significato) della realtà (della malattia) in un processo continuo di esperienza. Un flusso continuo che a partire da una percezione soggettivamente selettiva degli elementi disponibili (conoscenze, esperienze, eventi,etc.), organizza tali elementi in una mappa e li traduce in uno schema operativo di comportamento. Secondo Weick la realtà individuale si costruisce, mentre l’ambiente, il contesto, sono costruiti a priori. Le mappe cognitive che gli individui costruiscono influenzeranno le successive esperienze che si troveranno a dover fronteggiare nell’ambito dello stesso problema, in questo caso inerenti alla malattia diabetica. L’utilizzo del sensemaking applicato all’analisi dei processi di cura, pertanto, può diventare utile in particolare nei contesti di trattamento in cui la compliance e l’aderenza alle cure costituisce un fattore determinante nella gestione della patologia cronica, che prevede un modello di rapporto medico- paziente protratto nel tempo e centrato sulla possibilità di confronto rispetto alle modalità di cura e riuscita della stessa. La ricerca si è proposta pertanto di indagare attarverso la somminisrazione di interviste a medici e pazienti e attarverso al successiva analisi del testo e delle ricorrenze lingusitiche elaborate attraverso appositi software di ricostruire e mettere a confronto le rispettive mappe cognitive che stanno alla base delle rappresentazioni della malattia e della sua gestione e quindi dei comportamenti conseguenti di chi cura e di chi è curato.

Obiettivo di questo scritto è presentare una nuova procedura per implementare l’alta affidabilità (High Reliability) in contesti sociali e nel lavoro di gruppo utilizzando particolari forme di Long Life Learning. Si tratta del Laboratorio di Intonazione e di Ascolto (L.I.A.) che è stato individuato come spin-off della ricerca che l’èquipe del Dipartimento di Psicologia di Torino ha condotto dal 2001 al 2009.

Infections caused by ESBL-producing Enterobacteriaceae and carbapenemases producing bacteria are a growing phenomenon which is one of the leading causes of death among elderly or immunosuppressed patients and is also associated with a higher cost of hospitalization. As worldwide, also in Italy a steady and alarming increase of these microorganisms is reported. With the present paper we present a brief review of the prevalence of ESBL-producing and carbapenemase strains isolated at the Hospital - University Campus - Hospital “Luigi Sacco” in Milan between January 2007 and June 2012. Samples ESBLs positive (Vitek2: bioMérieux, France) were subjected to phenotype confirmation by E-test method (bioMérieux, France). In addition 34 K. pneumoniae carbapenemases producing strains collected between 2011 and 2012, were firstly confirmed with an Hodge test and then tested with a NASBA EasyQ KPCv1.0 test (bioMérieux, France) able to detect the bla KPC gene. The data collected showed a high prevalence of ESBLs and carbapenemases producing strains. 1828 out of 15585 were positive for ESBL with the following distribution: 15.6% E. coli, 13.0% K. pneumoniae, 3.6% Enterobacter spp, 7.7% P. mirabilis and 6% P. aeruginosa. Out of 1828, 193 samples (10.5%) were confirmed as positive and respectively 89.4% were E. Coli, 80% were K. pneumoniae and 89.5% were P. mirabilis. The 3.6% of strains were positive for carbapenemase: 45.3% were A. baumannii and 41.8% were P. aeruginosa. K. pneumoniae strains carbapenemase positive were confirmed in 100% of cases by the Hodge test and in 97% of cases by molecular investigation.

In the spring of 2009, a new variant of influenza A/H1N1 virus that had never been isolated before, was identified. From April 27 to December 31, 2009 the respiratory samples of 974 patients, obtained from suspected cases of pandemic influenza A virus infection, were analyzed at the Clinical Microbiology Laboratory of the “L. Sacco” University Hospital in Milan. The diagnosis of influenza A/H1N1 infection was performed initially through the use of different molecular biological methods: Seeplex® RV12 ACE Detection (Seegene), NUCLISENS® EASYQ® INFLUENZA A/B (bioMérieux), Influenza A/B Q-PCR Alert (Nanogen) running in parallel with rRT-PCR (CDC) to confirm the positivity to the new influenza virus, then was used a single specific test, Fast set H1N1v (Arrow Diagnostics). Retrospective study of data showed that 293 (30.1%) patients were positive for the new strain of influenza A/H1N1 virus and 8 (0.8%) for influenza A other than H1N1 virus.The distribution of influenza A/H1N1 cases showed two peaks, one on July (62.9%) and the other one on October (36%), moreover we observed that 155 patients (53%) out of 293 positive for influenza A/H1N1 virus aged under 20 years old. The first positivity peak was found in travelers and the second one, occurred 2-3 months prior to the classic seasonal epidemic influenza, was attributed to autochthonous cases , by which the virus had spread worldwide. The highest proportion of cases were among subjects aged from 0 to 20 years and, over this age the positivity rate decreased proportionally with increasing age, in agreement with data reported in other countries.

Gram stain and bacterial antigen detection are economic and rapid tests for the identification of the bacteria in cerebrospinal fluid (CSF) for the diagnosis of meningitis. Even if culture is the gold standard of these diagnosis, it requires long time (growth time). The purpose of our study was to compare in the laboratory diagnosis of meningitis real time PCR (Eurospital, Italy). with standard methods. Samples were collected in patients referred to L. Sacco Universital Hospital (range of age: 16 to 70 years) from September 2008 to July 2009. 9 out of 130 CFS samples investigated were positive in PCR but they produced different results to the other methods used.

An eighteen-month study (2008-2009) was carried out on patients, aged on average 30 months, admitted with gastroenteritis to the Paediatric Unit of the L. Sacco Hospital in Milan, Italy. Faecal samples of 154 patients were investigated for Rotavirus, Norovirus,Adenovirus, Enterovirus and Bocavirus. A total of 25 norovirus positive samples were selected for nucleotide sequence analysis, that allowed identify GII.2, GII.3 and GII.4 2006 virus variants (06 a, 06 b).

Objective Aim of our study was investigate the presence of enteric viruses like Norovirus, Bocavirus and Rotavirus in hospitalized children belong to Paediatrics Clinics of L. Sacco Hospital. Material and methods 150 faecal samples were investigated from January 2008- 2009, by PCR real time for Norovirus and Bocavirus; Rotavirus was detected by enzyme immunoassay. Results We obtain a positive result on total samples in percentage of 36%: Rotaviruses are estimated to cause more than 20% of gastroenteritis cases; Noroviruses 7.3% cases; Bocaviruses 6.6% cases. Rotaviruses infections occurred in children 1-4 years of age and for 2 cases at 7 and 13 years old. Illness typically happened in the cooler months from January to March even if there were few positive cases in September/October. Noroviruses and Bocaviruses infections occurred in children 1-2 years of age and their seasonality were respectively from September to December and from January to March for Bocaviruses. Conclusions The present results point out the importance to detect new viral gastrointestinal agents associated with paediatric illness.

Surveillace of viral gastoenteritis infections is very poor in Italy, even if starting from 2004 Norovirus became one of the most causative agent of infections in all the seasons. The aim of our study was to evaluate the isolation of Norovirus both in hospitalizes patients and communitary patients. From October 2006 to March 2008 we examined 400 samples. Our results showed only 15 sporadic cases in pediatric, HIV comunitary patients. These cases were analyzed by using an ELISA screening (Biopharm) and the results were confirmed with real time PCT (Argene).