Prevalence of hepatitis E virus in Italian pig herds. Preliminary results

Hepatitis E virus (HEV) is the causative agent of hepatitis E, and is an unenveloped positive sense single-stranded RNA wus. Swine HEV strains are genetically closely related to human strains from the same area, suggesting the occurrence of zoonotic transmission. Recently, human cases of hepatitis E have been linked to the consumption of raw or undercooked meat or organs from deer, wild boars or p1gs. The disease is now considered an emerging food-borne transmitted zoonosis. During 2006, a pilot investigation was performed to determine the prevalence of HEV in pig farms located in Northern Italy. 274 faecal samples were collected from healthy fattening animals (3-4 and 8-9 months of age) and from healthy breeding animals (gilts and sows) from 6 different farms, and analyzed using a Nested-RT-PCR targeting the open reading frame 2 (ORF2) region. Stool samples were suspended in water, and viral RNA extraction was performed using a commercial kit. Extracted viral RNA was subjected to RT-PCR amplification using degenerate primers conA 1-conS1 for the first amplification, and degenerate primers conA2-conS2 for the nested PCR, yielding a final fragment of 145 bp. HEV RNA was detected in sixty-nine of the 274 (25.2%) examined samples. None of the six farms resulted negative and the prevalence within the farms ranged between 2% and 60.5% For the characterization of the strains, randomly selected positive samples were subjected to nucleotide sequencing, and aligned with those present in the NCBI Data Bank Sequence analysis showed that all stra1ns were Swine Hepatitis E belonging to Genotype 3. These preliminary results confirm that swine HEV is widespread in Italian swine farms

Clostridium botulinum spores and toxin in mascarpone cheese and other milk products

A total of 1,017 mascarpone cheese samples, collected at retail, were analyzed for Clostridium botulinum spores and toxin, aerobic mesophilic spore counts, as well as pH, a(w) (water activity), and Eh (oxidation-reduction potential). In addition 260 samples from other dairy products were also analyzed for spores and botulinum toxin. Experiments were carried out on naturally and artificially contaminated mascarpone to investigate the influence of different temperature conditions on toxin production by C. botulinum. Three hundred and thirty-one samples (32.5%) of mascarpone were positive for botulinal spores, and 7 (0.8%) of the 878 samples produced at the plant involved in an outbreak of foodborne botulism also contained toxin type A. The chemical-physical parameters (pH, a(w), Eh) of all samples were compatible with C. botulinum growth and toxinogenesis. Of the other milk products, 2.7% were positive for C. botulinum spores. Growth and toxin formation occurred in naturally and experimentally contaminated mascarpone samples after 3 and 4 days of incubation at 28 degrees C, respectively

Toward optimal implementation of cancer prevention and control programs in public health: A study protocol on mis-implementation

Abstract Background Much of the cancer burden in the USA is preventable, through application of existing knowledge. State-level funders and public health practitioners are in ideal positions to affect programs and policies related to cancer control. Mis-implementation refers to ending effective programs and policies prematurely or continuing ineffective ones. Greater attention to mis-implementation should lead to use of effective interventions and more efficient expenditure of resources, which in the long term, will lead to more positive cancer outcomes. Methods This is a three-phase study that takes a comprehensive approach, leading to the elucidation of tactics for addressing mis-implementation. Phase 1: We assess the extent to which mis-implementation is occurring among state cancer control programs in public health. This initial phase will involve a survey of 800 practitioners representing all states. The programs represented will span the full continuum of cancer control, from primary prevention to survivorship. Phase 2: Using data from phase 1 to identify organizations in which mis-implementation is particularly high or low, the team will conduct eight comparative case studies to get a richer understanding of mis-implementation and to understand contextual differences. These case studies will highlight lessons learned about mis-implementation and identify hypothesized drivers. Phase 3: Agent-based modeling will be used to identify dynamic interactions between individual capacity, organizational capacity, use of evidence, funding, and external factors driving mis-implementation. The team will then translate and disseminate findings from phases 1 to 3 to practitioners and practice-related stakeholders to support the reduction of mis-implementation. Discussion This study is innovative and significant because it will (1) be the first to refine and further develop reliable and valid measures of mis-implementation of public health programs; (2) bring together a strong, transdisciplinary team with significant expertise in practice-based research; (3) use agent-based modeling to address cancer control implementation; and (4) use a participatory, evidence-based, stakeholder-driven approach that will identify key leverage points for addressing mis-implementation among state public health programs. This research is expected to provide replicable computational simulation models that can identify leverage points and public health system dynamics to reduce mis-implementation in cancer control and may be of interest to other health areas

Identification of Novel Linear Megaplasmids Carrying a ß-Lactamase Gene in Neurotoxigenic Clostridium butyricum Type E Strains

Since the first isolation of type E botulinum toxin-producing Clostridium butyricum from two infant botulism cases in Italy in 1984, this peculiar microorganism has been implicated in different forms of botulism worldwide. By applying particular pulsed-field gel electrophoresis run conditions, we were able to show for the first time that ten neurotoxigenic C. butyricum type E strains originated from Italy and China have linear megaplasmids in their genomes. At least four different megaplasmid sizes were identified among the ten neurotoxigenic C. butyricum type E strains. Each isolate displayed a single sized megaplasmid that was shown to possess a linear structure by ATP-dependent exonuclease digestion. Some of the neurotoxigenic C. butyricum type E strains possessed additional smaller circular plasmids. In order to investigate the genetic content of the newly identified megaplasmids, selected gene probes were designed and used in Southern hybridization experiments. Our results revealed that the type E botulinum neurotoxin gene was chromosome-located in all neurotoxigenic C. butyricum type E strains. Similar results were obtained with the 16S rRNA, the tetracycline tet(P) and the lincomycin resistance protein lmrB gene probes. A specific mobA gene probe only hybridized to the smaller plasmids of the Italian C. butyricum type E strains. Of note, a ß-lactamase gene probe hybridized to the megaplasmids of eight neurotoxigenic C. butyricum type E strains, of which seven from clinical sources and the remaining one from a food implicated in foodborne botulism, whereas this ß-lactam antibiotic resistance gene was absent form the megaplasmids of the two soil strains examined. The widespread occurrence among C. butyricum type E strains associated to human disease of linear megaplasmids harboring an antibiotic resistance gene strongly suggests that the megaplasmids could have played an important role in the emergence of C. butyricum type E as a human pathogen

Recreational and drinking waters as a source of norovirus gastroenteritis outbreaks: a review and update

The distribution of noroviruses is worldwide. In industrialized countries, noroviruses are the most common viral cause of gastroenteritis outbreaks and play an important role in sporadic gastroenteritis as well. Transmission may occur through the ingestion of contaminated foods or water, through person-to-person contact, or by way of direct contact with contaminated surfaces. Of particular importance is their ability to cause waterborne outbreaks linked either to the direct consumption of water or to its recreational uses. This article reviews the clinical manifestations and epidemiology of norovirus infection, and describes over 40 waterborne norovirus outbreaks, their respective probable sources of contamination and - where water samples were tested - the genetic types identified

Acetaminophen Removal from Aqueous Solutions by TiO2-X photo catalyst

Introduction: Pharmaceutical wastes are in group of emerging contaminants. These materials cannot be removed completely with conventional treatment methods of water and wastewater. Drug and its metabolites, due to the potential risks toxic and toxicity potential to humans and environment should be removed from the water resources. In this study, Acetaminophen photo catalytic removal from aqueous solutions was investigated by X zeolite modified with TiO2 (TiO2/ X zeolite). Methods: This study was experimental and carried out on a laboratory scale. To remove acetaminophen from aqueous solution, TiO2/X zeolite photo-catalyst under UV-C radiation (UV/TiO2-X process) was used. Acetaminophen concentration of soluble was measured using by spectrophotometer UV/Vis in λmax ~ 243nm. The optimal conditions of pH, catalyst dosage, acetaminophen initial concentration and reaction time were determined and also acetaminophen disintegration reaction kinetics was studied by TiO2-X catalyst. Data analysis was performed using descriptive statistics. Results: The results indicated that maximum removal of acetaminophen(95.45%) was related to 1 mg/L of initial concentration in the neutral pH and a catalyst concentration of 500 mg/L after 75min of start of photo-catalytic reaction. By decreasing concentration of acetaminophen its removal rates will increase. The Acetaminophen degradation kinetic with UV/TiO2-X process followed a pseudo-first order reaction with rate constants of  0.01446 min-1. Conclusion: The Photocatalytic method of UV/TiO2-X to remove acetaminophen from aqueous solutions has a high efficiency and is recommende

In vivo and in vitro assessment of the virulence of Listeria monocytogenes strains

To evaluate whether the in vitro model (invasion and intracellular growth in Caco-2 cells) for determining virulence is a suitable alternative to the in vivo model (50% lethal dose), we compared the levels of virulence obtained with the two models. We tested L. monocytogenes strains isolated from food and clinical samples during three episodes of listeriosis occurring in Italy in the period 1993-1995. We also tested L. monocytogenes strains isolated from food during official control activities. The results obtained from the tested strains varied according to the experimental method adopted: the L. monocytogenes strains featuring the same genetic pattern showed a greater uniformity of response in vivo than in vitro. We can conclude that the in vitro model may be used as an alternative to the animal model to determine Listeria spp pathogenicity, though it cannot distinguish levels of virulence within the L. monocytogenes species

Molecular Identification and Genetic Analysis of Norovirus Genogroups I and II in Water Environments: Comparative Analysis of Different Reverse Transcription-PCR Assays▿

Noroviruses have received increased attention in recent years because their role as etiologic agents in acute gastroenteritis outbreaks is now clearly established. Our inability to grow them in cell culture and the lack of an animal model hinder the characterization of these viruses. More recently, molecular approaches have been used to study the genetic relationships that exist among them. In the present study, environmental samples from seawater, estuarine water, and effluents of sewage treatment plants were analyzed in order to evaluate the role of environmental surface contamination as a possible vehicle for transmission of norovirus genogroups I and II. Novel broad-range reverse transcription-PCR/nested assays targeting the region coding for the RNA-dependent RNA polymerase were developed, amplifying fragments of 516 bp and 687 bp in the nested reactions for genogroups II and I, respectively. The assays were evaluated and compared against widely used published assays. The newly designed assays provide long regions for high-confidence BLAST searches in public databases and therefore are useful diagnostic tools for molecular diagnosis and typing of human noroviruses in clinical and environmental samples, as well as for the study of molecular epidemiology and the evolution of these viruses