emerging and potentially emerging viruses in water environments

Among microorganisms, viruses are best fit to become emerging pathogens since they are able to adapt not only by mutation but also through recombination and reassortment and can thus become able to infect new hosts and to adjust to new environments. Enteric viruses are among the commonest and most hazardous waterborne pathogens, causing both sporadic and outbreak-related illness. The main health effect associated with enteric viruses is gastrointestinal illness, but they can also cause respiratory symptoms, conjunctivitis, hepatitis, central nervous system infections, and chronic diseases. Non-enteric viruses, such as respiratory and epitheliotrophic viruses are not considered waterborne, as they are not readily transmitted to water sources from infected individuals. The present review will focus on viral pathogens shown to be transmitted through water. It will also provide an overview of viruses that had not been a concern for waterborne transmission in the past, but that may represent potentially emerging waterborne pathogens due to their occurrence and persistence in water environments

Quantitative Microbial Risk Assessment as support for bathing waters profiling

Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an areaspecific QMRA model on four pathogens, using fecal indicator concentrations (E. coil, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coll. and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment

Emerging and potentially emerging viruses in water environments

Among microorganisms, viruses are best fit to become emerging pathogens since they are able to adapt not only by mutation but also through recombination and reassortment and can thus become able to infect new hosts and to adjust to new environments. Enteric viruses are among the commonest and most hazardous waterborne pathogens, causing both sporadic and outbreak-related illness. The main health effect associated with enteric viruses is gastrointestinal illness, but they can also cause respiratory symptoms, conjunctivitis, hepatitis, central nervous system infections, and chronic diseases. Non-enteric viruses, such as respiratory and epitheliotrophic viruses are not considered waterborne, as they are not readily transmitted to water sources from infected individuals. The present review will focus on viral pathogens shown to be transmitted through water. It will also provide an overview of viruses that had not been a concern for waterborne transmission in the past, but that may represent potentially emerging waterborne pathogens due to their occurrence and persistence in water environments

Emerging and potentially emerging viruses in water environments

Among microorganisms, viruses are best fit to become emerging pathogens since they are able to adapt not only by mutation but also through recombination and reassortment and can thus become able to infect new hosts and to adjust to new environments. Enteric viruses are among the commonest and most hazardous waterborne pathogens, causing both sporadic and outbreak-related illness. The main health effect associated with enteric viruses is gastrointestinal illness, but they can also cause respiratory symptoms, conjunctivitis, hepatitis, central nervous system infections, and chronic diseases. Non-enteric viruses, such as respiratory and epitheliotrophic viruses are not considered waterborne, as they are not readily transmitted to water sources from infected individuals. The present review will focus on viral pathogens shown to be transmitted through water. It will also provide an overview of viruses that had not been a concern for waterborne transmission in the past, but that may represent potentially emerging waterborne pathogens due to their occurrence and persistence in water environments

Viral infections acquired indoors through airborne, droplet or contact transmission

BACKGROUND: Indoor human environments, including homes, offices, schools, workplaces, transport systems and other settings, often harbor potentially unsafe microorganisms. Most previous studies of bioaerosols in indoor environments have addressed contamination with bacteria or fungi. Reports on the presence of viral aerosols in indoor air are scarce, however, despite the fact that viruses are probably the most common cause of infection acquired indoor. OBJECTIVE: This review discusses the most common respiratory (influenza viruses, rhino-viruses, coronaviruses, adenoviruses, respiratory syncytial viruses, and enteroviruses) and gastrointestinal (noroviruses) viral pathogens which can be easily transmitted in indoor environments. RESULTS: The vast majority of studies reviewed here concern hospital and other health facilities where viruses are a well-known cause of occupational and nosocomial infections. Studies on other indoor environments, on the other hand, including homes, non-industrial workplaces and public buildings, are scarce. CONCLUSIONS: The lack of regulations, threshold values and standardized detection methods for viruses in indoor environments, make both research and interpretation of results difficult in this field, hampering infection control efforts. Further research will be needed to achieve a better understanding of virus survival in aerosols and on surfaces, and to elucidate the relationship between viruses and indoor environmental characteristics

Mucosal and cutaneous human papillomaviruses detected in raw sewages.

Epitheliotropic viruses can find their way into sewage. The aim of the present study was to investigate the occurrence, distribution, and genetic diversity of Human Papillomaviruses (HPVs) in urban wastewaters. Sewage samples were collected from treatment plants distributed throughout Italy. The DNA extracted from these samples was analyzed by PCR using five PV-specific sets of primers targeting the L1 (GP5/GP6, MY09/MY11, FAP59/64, SKF/SKR) and E1 regions (PM-A/PM-B), according to the protocols previously validated for the detection of mucosal and cutaneous HPV genotypes. PCR products underwent sequencing analysis and the sequences were aligned to reference genomes from the Papillomavirus Episteme database. Phylogenetic analysis was then performed to assess the genetic relationships among the different sequences and between the sequences of the samples and those of the prototype strains. A broad spectrum of sequences related to mucosal and cutaneous HPV types was detected in 81% of the sewage samples analyzed. Surprisingly, sequences related to the anogenital HPV6 and 11 were detected in 19% of the samples, and sequences related to the "high risk" oncogenic HPV16 were identified in two samples. Sequences related to HPV9, HPV20, HPV25, HPV76, HPV80, HPV104, HPV110, HPV111, HPV120 and HPV145 beta Papillomaviruses were detected in 76% of the samples. In addition, similarity searches and phylogenetic analysis of some sequences suggest that they could belong to putative new genotypes of the beta genus. In this study, for the first time, the presence of HPV viruses strongly related to human cancer is reported in sewage samples. Our data increases the knowledge of HPV genomic diversity and suggests that virological analysis of urban sewage can provide key information useful in supporting epidemiological studies

An Italian survey on the microbiological safety of toys containing aqueous media

Aims The purpose of the present investigation is to fill the current gap in information regarding the microbiological quality of toys containing aqueous media and the related risks for users. Methods Over 18 years, a total of 491 sealed toys containing aqueous media were analysed using conventional microbial culture methods. In addition, molecular methods (PCR/nested RT-PCR, followed by Sanger sequencing) were employed to test for enteric viruses (enteroviruses and adenoviruses) in a subset of toys; subsequently, the infectivity of the positive samples was tested on cell cultures. Results Of the examined toys, 23.8% were noncompliant with the limits of the European guideline. The most frequently exceeded limits were those for Aerobic bacteria (84.6%), and Pseudomonas aeruginosa (29.9%). Other opportunistic bacterial species that were frequently detected were Stenotrophomonas maltophilia, Pseudomonas fluorescens, Burkholderia cepacia, Sphingomonas paucimobilis and Comamonas acidovorans. In a subset of 28 samples, adenovirus (25%) and enterovirus (11%) genome was also found to be present, although the samples with viral positivity did not show infectivity after inoculation on appropriate cell monolayers. Conclusions The results indicate a condition of microbial exposure related to the use of toys containing aqueous media. Significance and Impact of Study The investigation highlights the need for more stringent monitoring during the production, packaging and storage of toys containing aqueous matrices in order to safeguard children's health

Valutazione microbiologica di prodotti di compostaggio: aspetti normativi e igienico-sanitari Procedure operative per lo svolgimento di indagini microbiologiche

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 , Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Phylogenetic tree constructed with the sequences obtained by Method A (L1 region).

<p>The tree was constructed using the Maximum Likelihood method based on the Kimura 2-parameter model. The sequences identified in this study are in bold. The percentage of trees in which the associated taxa clustered together is shown next to the branches. Bootstrap values higher than 70% are shown. HPV prototypes reported in the phylogenetic tree are: HPV6b, X00203; HPV11, M14119; HPV16, K02718; HPV25, X74471; HPV120, GQ845442; AJ000150; AF048746. A feline papillomavirus type 2 (EU796884) was included as an outgroup. Identical sequences obtained from the different plasmid cloned or identical sequences obtained from the nested and hemi-nested amplicons were not included in the tree. Sequences obtained from different clones were given an alphabetical code (ID sample “a”, “b”); sequences obtained from the hemi-nested reaction were marked with an asterisk.</p