Face masks. Technical, technological and functional characteristics and hygienic-sanitary aspects related to the use of filtering mask in the community.

INTRODUCTION: The health emergency caused by the spread of SARS-COV-2 virus has required the adoption of passive measures against contagion, such as social distancing. The use of filtering masks, of the different types available on the market, such as surgical and facial filtering masks (FFP1, FFP2 and FFP3), is also recommended. OBJECTIVES: The aim of this paper, within the Italian and European regulatory reference framework, is to suggest a rational application of existing methodologies that enable to know and assess the features and/or make a face mask intended to be used by the community. In addition to this, the study aims to provide a correct regulatory framework and useful information for a correct use and disposal of face masks. Another purpose is the assessment of the hygienic, sanitary and regulatory aspects related to the use and disposal of face masks. METHODS: The analysis of filtering masks is based on the review of scientific literature, the state of art of technology and the filtering means/materials available. Reference is made to filtering mechanisms and devices, the testing methods, the technical, manufacturing and performance features, and to the Italian and European regulatory reference framework. Reference is also made to the hygienic, sanitary and regulatory aspects related to the use and disposal of face masks. RESULTS: Surgical masks or, alternatively, filtering masks with a filtration efficiency between 90% and 95% for 3-µm particles, are the most practicable choice with minor contraindications. The reusable type of mask is conceptually superior compared to single-use masks, but cleaning procedures to be followed are quite complex and not always described in a clear way. CONCLUSIONS: The definition of rigorous and repeatable tests on mask filtration capacity, breathability, wearability, duration of use, regeneration, as well as safe disposal methods, are the main way to provide users with correct selection and use criteria. The results must be disclosed and disseminated quickly.

Enteric viruses, somatic coliphages and Vibrio species in marine bathing and non-bathing waters in Italy.

Microbial safety of recreational waters is a significant public health issue. In this study we assessed the occurrence and quantity of enteric viruses in bathing and non-bathing waters in Italy, in parallel with microbial faecal indicators, somatic coliphages and Vibrio spp. Enteric viruses (aichivirus, norovirus and enterovirus) were detected in 55% of bathing water samples, including samples with bacterial indicator concentrations compliant with the European bathing water Directive. Aichivirus was the most frequent and abundant virus. Adenovirus was detected only in non-bathing waters. Somatic coliphages were identified in 50% bathing water samples, 80% of which showed simultaneous presence of viruses. Vibrio species were ubiquitous, with 9 species identified, including potential pathogens (V. cholerae, V. parahaemoylticus and V. vulnificus). This is the first study showing the occurrence and high concentration of Aichivirus in bathing waters and provides original information, useful in view of a future revision of the European Directive.

A study on the microbial quality of sealed products for feminine hygiene.

INTRODUCTION: Sanitary tampons have been in existence for over 60 years. Their use may present certain health risks, potentially associated with an abnormal change of microbial flora in the vagina (e.g., toxic shock syndrome). Tampon production and marketing are regulated differently in different countries. In Australia, Canada and the USA, tampons are classified as Class-II medical devices and their marketing requires pre-clinical and clinical studies, including microbiological trials. In Europe, tampons are considered consumer products and safety-related data are provided only if the manufacturer deems them to be useful. Sterility of these products is not requested by law; thus they may represent a potential vehicle for microorganisms. Due to the lack of data on microbial characteristics of tampons, an analytical investigation was carried out to characterize and quantify the microbial flora present on sealed tampons of various brands present on the market in Italy. METHODS: Traditional cultural methods were used to characterize and quantify bacteria and fungi. Identification of colonies was performed with biochemical techniques. RESULTS: Results showed low microbial concentrations in 93% of the positive samples. A rare presence of opportunistic pathogens was detected and a few samples (6%) were characterized by bacterial species of human origin. CONCLUSIONS: In the light of these data, the examined tampons were found to have good hygienic quality. Nevertheless, to minimize the microbial risks linked to the use of these products, strict hygienic rules during their production and manipulation have to be adopted.

First detection of papillomaviruses and polyomaviruses in swimming pool waters: unrecognized recreational water-related pathogens?

AIMS: Viral outbreaks associated with swimming pools have been described worldwide. The objective of this study was to examine the extent of viral contamination in indoor and outdoor swimming pools. METHODS AND RESULTS: Pools were examined for the presence of human enteric viruses (adenovirus, norovirus and enterovirus) and nonenteric viruses (papillomavirus and polyomavirus-BK, JC, KI, WU and Merkel cell). Bacteriological parameters were also evaluated. The analysed pool waters met microbiological quality standards. Enteric viruses were not detected. On the other hand, papillomaviruses (HPV8, 12, 23, 25, 120 and unclassified HPVs) and polyomaviruses (JC and Merkel cell polyomaviruses) were detected in 9/14 samples (64%). The number of HPV DNA copies in pool waters, measured by quantitative Real-time PCR, ranged from 1.27E+04 to 1.13E+05/10L. CONCLUSION: Results show that a variety of nonenteric viruses may be discharged in pool waters by various secretions and excretions from infected individuals or asymptomatic carriers. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report on human papillomaviruses and polyomaviruses in swimming pools. The likelihood that these viruses can be transmitted by recreational activities deserves to be explored in future studies.

An Italian investigation on non-tuberculous mycobacteria in an urban water supply.

BACKGROUND: Atypical or non-tuberculous mycobacteria (NTM) are considered opportunistic pathogenic bacteria. They are natural inhabitants of a broad variety of environmental reservoirs, including natural and treated waters. Due to the lack of Italian studies on these microorganisms in drinking water, an investigation was carried out on their occurrence and on species present in a municipal water distribution system in Rome. The presence of the traditional indicators of faecal contaminations and free living amoebae were also verified. METHODS: Two different methodological approaches based on cultural and molecular techniques have been applied in parallel. RESULTS: Mean concentrations of NTM obtained with the two analytical methodologies were roughly 102 CFU/L. Among the numerous NTM species identified, M. chelonae was the most frequently isolated. No correlation of NTM with indicators of faecal contamination and amoebae was found. CONCLUSIONS: Mycobacteria can be present even if routine tests show water to have an excellent hygienic quality.

[Comparison of cultural methods for the recovery of Pseudomonas aeruginosa: the UNI EN ISO 16266 reference method and the alternative method Pseudalert®]. / Confronto di metodi colturali per il rilevamento di Pseudomonas aeruginosa: il metodo di riferimento UNI EN ISO 16266 e il metodo alternativo Pseudalert®.

BACKGROUND: For the water analysis, for Pseudomonas aeruginosa a presumptive positive result can be achieved in 40- 48 hours using the traditional membrane filtration technique followed by an additional 24-48 hour confirmation stage. Conversely, the Pseudalert Quanti-Tray™ method can give confirmed results after 24-28 hours. In this case, actively growing strains of Pseudomonas aeruginosa show a confirmed positive result when a specific enzyme cleaving the substrate in the reagent produces a blue fluorescence under 365 nm ultraviolet light. A comparison of the performance of the Pseudalert respect to the standard method was conducted using statistical methods. METHODS: Drinking water was analyzed in parallel with the membrane filtration technique using Pseudomonas CN agar (UNI EN ISO 16266) and the Pseudalert. Confirmation test are requested by the standard method and although Pseudalert Quanti-Tray™ gives confirmed results, all the positive isolates were also confirmed. Data were analyzed by statistical methods. RESULTS: For drinking water, Pseudalert showed a very high sensitivity (98,8%) and a high percentage of specificity (96,8%). From a total of 889 positive isolates, a very high confirmation rates (99,3%) was calculated. Statistical analyses confirmed that the two methods were not statistically different. CONCLUSIONS: These results indicate that the Pseudalert produces confirmed results in a shorter time than the standard reference method allowing the detection of Pseudomonas aeruginosa with no further confirmation steps. It could be a valid alternative method for the water analysis.

Occurrence of Giardia and Cryptosporidium in Italian water supplies.

A total of 21 samples: raw water (RW) samples; water samples after coagulation with aluminium sulfate (clarified water: CW); and water after chlorination (treated water: TW) from a water purification plant that treats river surface water from the neighbourhood of Foggia (Italy), were analysed for the presence of Giardia cysts and Cryptosporidium oocysts. Bacteriological indicator of faecal contamination (total and faecal coliforms, faecal streptococci,), total bacterial count at 22 and 36 degrees C and physicochemical parameters (turbidity, temperature, pH) were evaluated. Cryptosporidium oocysts were not found in any samples examined, while Giardia cysts were found only in RW samples, with the maximal concentration of 8 cysts/100 l. A positive correlation was found between the Giardia densities and quality parameters such as TC, FC and TBC at 22 degrees C. Giardia levels in raw water samples correlated (p < 0.05) with TC, FC and with temperature. No other water quality parameters was consistently correlated with cysts level.

Peracetic acid and sodium hypochlorite effectiveness in reducing resistant stages of microorganisms.

A comparative study on the efficacy of peracetic acid and sodium hypochlorite in inactivating resistant stages of microorganisms such as Cryptosporidium, Giardia and Cl. perfingens was carried out. Furthermore the evaluation of the potential reciprocal correlation among the concentrations of the organisms was performed. The results obtained indicate that, at the same experimental conditions, peracetic acid and sodium hypochlorite have nearly similar reduction power against the resistant stages of Giardia and Cl. perfringens. Both the oxidants are instead less efficient in the abatement of Cryptosporidium oocysts. Findings have also confirmed our previous studies on the absence of association between Clostridium and the protozoa.

[Hygienic aspects of the Tiber river: presence of pathogenic protozoa and correlation with microbiological and physico-chemical parameters]. / Aspetti igienico-sanitari delle acque del flume Tevere: presenza di protozoi patogeni e rapporti di correlazione con parametri microbiologici e chimico-fisici.

An investigation on the hygienic quality of the Tiber river was conducted with the aim both to enumerate Giardia cysts and Cryptosporidium oocysts in the water and to determine possible correlations between them and bacterial indicators, pathogens and physico-chemical parameters. A low hygienic water quality was evidenced, with high counts of microorganisms. Furthermore, variable concentrations of Giardia and Cryptosporidium were observed. No correlation was found between the protozoa concentrations and that of the other microorganisms, whilst a significant correlation with redox potential and Giardia cysts was calculated.

[A preliminary investigation on the occurrence of protozoa in swimming pools in Italy]. / Ricerca di protozoi nelle acque di piscina in Italia: risultati di un'indagine preliminare.

In Italy controls on the hygienic quality of swimming pools are fixed by the Accordo tra il Ministero della Salute, le regioni e le province autonome di Trento e di Bolzano, come into force in 2003. In the present study swimming pools were investigated from the microbiological point of view on the basis of the new legislation. Contemporaneously, for the first time in Italy, analytical controls on the occurrence of the protozoa Cryptosporidium and Giardia were performed with both techniques of immunofluorescence and polymerase chain reaction. Results evidenced a good water quality when the bacterial parameters stated by law were considered. However in some swimming pools, the protozoa were also recovered. Factors affecting the use of molecular techniques on the analysis of environmental samples are also put into evidence.

[Systematic study of microbiological and parasitological quality of drinking water: the example of Cassino]. / Uno studio sistematico sulla qualità microbiologica e parassitologica delle acque potabili: l'esempio del cassinate.

In order to evaluate microbial and parasitological quality of water resources located in the area of Cassino, different typologies of water were monitored during the course of 2002. Analytical results showed that neither water sources nor chlorinated water were affected by microbial and parasitological contamination. Surface water can be used as drinking water after suitable treatment processes. The constant occurrence of parasitic protozoa in sewage shows their spreading in the environment; nevertheless their absence in groundwater and tap water suggests a good level of hygienic quality in water management.

Sanitary quality of marine sediments and sands from an Italian beach.

Microbiological surveys were carried out on marine sands and sediments collected at a sandy beach along a coastal area close to Rome, Italy. Low densities of faecal indicator bacteria were recovered, and among them enterococci outnumbered the coliforms. The group of staphylococci was in a fairly constant concentration throughout the period of sampling. Some statistically significant correlations were calculated between yeasts and moulds, Escherichia coli and enterococci and between the latter and Clostridium spores. The data obtained could be a reference point for further studies.

Pilot-plant comparative study of peracetic acid and sodium hypochlorite wastewater disinfection.

Peracetic acid (PAA) use in wastewater disinfection was assessed by examining its performances in a pilot plant fed by the effluent from a conventional activated-sludge treatment plant. The influence of PAA initial concentrations (0.5-4.0 mg/l) and contact times (8-38 min) on the presence of seven microorganisms (total coliforms, fecal coliforms, fecal streptococci, Escherichia coli, Pseudomonas sp., Salmonella sp., and bacteriophages anti-E. coli) and on residual biocide and halogenated organic compound (AOXs) concentrations were evaluated. The data so obtained were compared to the corresponding results acquired using sodium hypochlorite (HYP) in the same experimental conditions. The biocide effect of PAA against total and fecal coliforms, E. coli, Pseudomonas sp. and Salmonella sp. was similar to that shown by HYP. The former disinfectant was, however, less efficient than the latter in the reduction of fecal streptococci and bacteriophages anti-E. coli. In both cases the biocide quantities initially introduced in the sewage resulted in the presence of significant concentrations at the end of the contact time. No significant variation of AOX content was detected in the effluent treated with PAA, whereas a progressive increment of such compounds was found when increasing quantities of HYP were added to the sewage.

Fate of bacterial indicators, viruses and protozoan parasites in a wastewater multi-component treatment system.

The extent of reduction in selected microrganisms was tested at a multi-component wastewater treatment plant that treats sewage for a potential re-use in agriculture. The aim of the investigation was to evaluate possible reciprocal correlation among the different microrganisms and to compare the removal of two encysted pathogenic protozoa with that of microbial indicators, Clostridium perfringens spores, enteroviruses and bacteriophages. Samples collected included the raw wastewater, the chlorinated effluent and the effluent after an ultraviolet light treatment. All of the raw sewage samples were positive for Cryptosporidium oocysts and Giardia cysts, as well as for the other microorganisms tested but the bacteriophage B40-8. The data obtained confirm the removal efficiency of the entire process for indicator bacteria but also show the low and variable removal efficiency for the other microbial parameters, such as Giardia and Cryptosporidium, enteroviruses and Clostridium perfringens spores. Reciprocal correlation between Cryptosporidium and Giardia (oo)cysts and the other microbial groups was not demonstrated. The results confirm the resistance of Clostridium perfringens spores, enteroviruses and protozoa to chlorination and demonstrate the relative persistence of these organisms in the effluents even during the ultraviolet light treatment. The yields also emphasise the influence of the analytical method for the determination of protozoan parasites.

Genomic heterogeneity of environmental and clinical aeromonads.

Thirty-three isolates of Aeromonas from environmental sources and clinical samples were tested and the results, obtained using the pulsed field gel electrophoresis (PFGE) technique, were compared with those obtained by biochemical typing. On the basis of their biochemical characteristics 31 strains was assigned to one of the recognised groups or species within the Aeromonas genus and 2 strains to the species Vibrio fluvialis. These latter were nevertheless found to belong to the Aeromonas genus on the basis of the chromosomal DNA analysis. Among the clinical isolates the biochemical analysis showed greater uniformity. A low correlation between molecular and traditional typing methods was observed with a wider heterogeneity at the genomic level. The results showed the difficulty of discriminating Aeromonas isolates by conventional biochemical methods. The genomic analysis performed by PFGE can be a more effectual technique, which can be used for epidemiological and ecological studies of the microorganisms belonging to the Aeromonas group.

Size and charge isomers of acetylcholinesterase in the cerebral cortex of young and aged rats.

Previous studies in this laboratory showed an age-related decline of acetylcholinesterase (AChE) activity in the cerebral cortex of rats. In the present study the age-related differences in enzymatic activity were evaluated in terms of individual molecular forms. Extracts containing total, soluble and membrane-bound AChE were analyzed both by ultracentrifugation in sucrose gradient and by non-denaturing gradient polyacrylamide gel electrophoresis. By ultracentrifugation two molecular forms, namely 10S and 4S (corresponding to tetrameric-G4 and monomeric-G1 forms, respectively) were separated in extracts of total and soluble AChE, while only 10S forms were present in extracts of membrane-bound AChE. Electrophoresis of soluble AChE extracts revealed slowly- and fast-migrating bands, grouped in two clusters of at least three bands each; membrane-bound AChE contained only a single slowly-migrating band. Electrophoresis of the single forms isolated by ultracentrifugation showed that slowly- and fast-migrating bands corresponded to G4 and G1 forms, respectively. Therefore, in soluble AChE no one-to-one relationship between charge- and size-isomers was observed; on the contrary, such relationship has been shown for membrane-bound AChE. This implies that soluble G4 forms and membrane-bound-G4 forms are electrophoretically different, being heterogeneous the former and homogeneous the latter. The age-related decline of total AChE, accompanied by a decrease of G4/G1 ratio, depended mainly on a decrease of membrane-bound AChE while soluble AChE and its G4/G1 ratio was unchanged. The qualitative pattern of charge isomers was not modified by aging.