•Fluoroquinolones and trimethoprim could select for AMR in French human-polluted environments.•Paucity of data and lack of spatial and temporal sampling strategies preclude a thorough analysis.•E. ...coli resistant to 3rd-generation cephalosporins or producing ESBL and intl1 are proposed as AMR indicators.•Priority antibiotics to be monitored in the aquatic environment are recommended.•Harmonizing sampling and analytical methods is a priority to monitor environmental contamination.
Antimicrobial resistance (AMR) is a major global public health concern, shared by a large number of human and animal health actors. Within the framework of a One Health approach, actions should be implemented in the environmental realm, as well as the human and animal realms. The Government of France commissioned a report to provide policy and decision makers with an evidential basis for recommending or taking future actions to mitigate AMR in the environment. We first examined the mechanisms that underlie the emergence and persistence of antimicrobial resistance in the environment. This report drew up an inventory of the contamination of aquatic and terrestrial environments by AMR and antibiotics, anticipating that the findings will be representative of some other high-income countries. Effluents of wastewater treatment plants were identified as the major source of contamination on French territory, with spreading of organic waste products as a more diffuse and incidental contamination of aquatic environments. A limitation of this review is the heterogeneity of available data in space and time, as well as the lack of data for certain sources.
Comparing the French Measured Environmental Concentrations (MECs) with predicted no effect concentrations (PNECs), fluoroquinolones and trimethoprim were identified as representing high and medium risk of favoring the selection of resistant bacteria in treated wastewater and in the most contaminated rivers. All other antibiotic molecules analyzed (erythromycin, clarithromycin, azithromycin, tetracycline) were at low risk of resistance selection in those environments. However, the heterogeneity of the data available impairs their full exploitation. Consequently, we listed indicators to survey AMR and antibiotics in the environment and recommended the harmonization of sampling strategies and endpoints for analyses.
Finally, the objectives and methods used for the present work could comprise a useful example for how national authorities of countries sharing common socio-geographic characteristics with France could seek to better understand and define the environmental dimension of AMR in their particular settings.
In recent years, raw fruits and vegetables have frequently been involved in foodborne transmission to humans of enteric viruses, particularly noroviruses and hepatitis A virus (HAV). Although viral ...contamination can occur during all steps of food processing, primary production is a critical stage on which prevention measures must be focused to minimize the risk of infection to consumers. Postharvest sanitation may be a valid technological solution for decreasing the bacterial load on fresh raw material, but there is a lack of data concerning the effectiveness of this process on enteric viruses. In this study, we compared the survival of two human norovirus surrogates, the feline calicivirus (FCV), and the murine norovirus (MNV-1), and of HAV on lettuce after water washing with bubbles and with or without ultrasound, and washing with bubbles in the presence of active chlorine (15
ppm) or peroxyacetic acid-based disinfectant (100
ppm). Cell culture and quantitative RT-PCR assays were used to detect and quantify the viruses on the surface of the lettuce after the sanitizing treatments. Levels of viral inactivation on the lettuce leaves were not significantly different between washing with bubbles and washing with bubbles plus ultrasound and were not dependant on the quantification method. A simple washing without disinfectant resulted in a decrease of approximately 0.7 log units in the quantity of virus detected for HAV and FCV and of 1.0 log unit for MNV-1.
In the experimental set-up including a washing step (with or without ultrasound) followed by washing for 2
min in the presence of disinfectants, 15
ppm of active chlorine was found more effective for inactivating FCV (2.9 log units) than HAV and MNV-1 (1.9 log units and 1.4 log units, respectively) whereas 100
ppm of peroxyacetic-based biocide was found effective for inactivating FCV (3.2 log units) and MNV-1 (2.3 log units), but not HAV (0.7 log units). Quantitative RT-PCR results indicated that the presence of viral RNA did not correlate with the presence of infectious viruses on disinfected lettuce, except for MNV-1 processed with chlorine (15
ppm). In comparison with water washing, a substantial additional decrease of genomic FCV titer (1.1 log units) but no significant reduction of the genomic titers of HAV and MNV-1 were found on lettuce treated with chlorine (15
ppm). No significant effect of the disinfection step of lettuce with peroxyacetic-based biocide (100
ppm peracetic acid) was found by qRT-PCR on all genomic viral titers tested. This study illustrates the necessity of determining the effectiveness of technological processes against enteric viruses, using a relevant reference such as HAV, in order to reduce the risk of hepatitis and gastroenteritis by exposure to vegetables.
► We compared the survival of FCV, MNV-1, HAV on lettuces after sanitizing treatments. ► We tested water washing, chlorine, and a peroxyacetic acid-based disinfectant. ► We used qRT-PCR and cell culture for virus monitoring. ► Washing resulted in a decrease of approximately 1 logarithmic unit of virus. ► We determined the differences in the resistance of viruses to biocides.
Since 2003, there has been significant concern about the possibility of an outbreak of avian influenza virus subtype H5N1. Moreover, in the last few months, a pandemic of a novel swine-origin ...influenza A virus, namely A(H1N1), has already caused hundreds of thousands of human cases of illness and thousands of deaths. As those viruses could possibly contaminate water resources through wild birds excreta or through sewage, the aim of our work was to find out whether the treatment processes in use in the drinking water industry are suitable for eradicating them. The effectiveness of physical treatments (coagulation–flocculation–settling, membrane ultrafiltration and ultraviolet) was assessed on H5N1, and that of disinfectants (monochloramine, chlorine dioxide, chlorine, and ozone) was established for both the H5N1 and H1N1 viruses.
Natural water samples were spiked with human H5N1/H1N1 viruses. For the coagulation–settling experiments, raw surface water was treated in jar-test pilots with 3 different coagulating agents (aluminum sulfate, ferric chloride, aluminum polychorosulfate). Membrane performance was quantified using a hollow-fiber ultrafiltration system. Ultraviolet irradiation experiments were conducted with a collimated beam that made it possible to assess the effectiveness of various UV doses (25–60 mJ/cm
2). In the case of ozone, 0.5 mg/L and 1 mg/L residual concentrations were tested with a contact time of 10 min. Finally, for chlorine, chlorine dioxide and monochloramine treatments, several residual oxidant target levels were tested (from 0.3 to 3 mg/L) with contact times of 5–120 min. The infectivity of the H5N1 and H1N1 viruses in water samples was quantified in cell culture using a microtiter endpoint titration.
The impact of coagulation–settling on the H5N1 subtype was quite low and variable. In contrast, ultrafiltration achieved more than a 3-log reduction (and more than a 4-log removal in most cases), and UV treatment was readily effective on its inactivation (more than a 5-log inactivation with a UV dose of 25 mJ/cm
2). Of the chemical disinfection treatments, ozone, chlorine and chlorine dioxide were all very effective in inactivating H5N1 and H1N1, whereas monochloramine treatment required higher doses and longer contact times to achieve significant reductions.
Our findings suggest that the water treatment strategies that are currently used for surface water treatment are entirely suitable for removing and/or inactivating influenza A viruses. Appropriate preventive actions can be defined for single disinfection treatment plants.
The aim of this work was to develop a filtering biocidal polypropylene (PP) nonwoven textile structure to block and inactivate airborne bacteria and viruses. PP filters were functionalized with a ...cyclodextrin (CD)-polycarboxylic acid-crosslinked polymer (PP-CD) through a pad/dry/curing process, and were then activated by padding in an alkyl dimethyl benzalkonium chloride (ADBAC) solution. The textile finishing process parameters were optimized with the perspective of mass production, considering the threshold temperature necessary for provoking crosslinking and the limitation of the low thermal stability of PP. The use of an aqueous solution containing hydroxypropyl-β-cyclodextrin (HPβCD), 1,2,3,4-butanetetracarboxylic acid (BTCA), ammonium hypophosphite (AH), and a surfactant allowed immobilization of the optimal quantity of cyclodextrin polymer under curing for 5 minutes at 125 °C without affecting the nonwoven PP structure. The presence of CD drastically increased the sorption of ADBAC on the textiles. There was leaching of ADBAC at the first rinsing and then satisfactory fastness at the second and third rinsings, revealing adsorption mechanisms by weak physical interactions, ionic interactions, and inclusion of ADBAC inside the CD cavities. SEM revealed no clogging of the nonwoven pores, nor any increase in the air flow resistance, as evaluated by pressure drop measurements. The filtration efficiency of particulate matter PM
3.0
and PM
0.5
was moderately affected, in contrast to that of PM
0.3
, which greatly decreased due to the loss of the electrostatic charge of the filter upon the functionalization process. Bactericidal tests resulted in a reduction of 3 log
10
against
Staphylococcus aureus
, and for virucidal tests on human coronavirus HCoV-229E, there was a reduction of 3.4 log
10
, with both strains undergoing 20 minutes of contact. Finally, the filter we developed is manufacturable by a scalable process, and because of its filtration and biocidal performances, it is a choice material as a self-disinfecting layer in the fabrication of facepiece respirators.
The aim of this work was to develop a filtering biocidal polypropylene (PP) nonwoven textile structure to block and inactivate airborne bacteria and viruses.
The 2019 coronavirus outbreak and worsening air pollution have triggered the search for manufacturing effective protective masks preventing both particulate matter and biohazard absorption through ...the respiratory tract. Therefore, the design of advanced filtering textiles combining efficient physical barrier properties with antimicrobial properties is more newsworthy than ever. The objective of this work was to produce a filtering electrospun membrane incorporating a biocidal agent that would offer both optimal filtration efficiency and fast deactivation of entrapped viruses and bacteria. After the eco-friendly electrospinning process, polyvinyl alcohol (PVA) nanofibers were stabilized by crosslinking with 1,2,3,4-butanetetracarboxylic acid (BTCA). To compensate their low mechanical properties, nanofiber membranes with variable grammages were directly electrospun on a meltblown polypropylene (PP) support of 30 g/m
. The results demonstrated that nanofibers supported on PP with a grammage of around only 2 g/m
presented the best compromise between filtration efficiencies of PM
, PM
, and PM
and the pressure drop. The filtering electrospun membranes loaded with benzalkonium chloride (ADBAC) as a biocidal agent were successfully tested against
and
and against human coronavirus strain HCoV-229E. This new biocidal filter based on electrospun nanofibers supported on PP nonwoven fabric could be a promising solution for personal and collective protection in a pandemic context.
Enteric viruses, particularly human Noroviruses (NoV) and hepatitis A virus (HAV), are key food-borne pathogens. The attachment of these pathogens to foodstuff and food-contact surfaces is an ...important mechanism in the human contamination process. Studies were done to investigate the nature of the physicochemical forces, such as hydrophobic and electrostatic ones, involved in the interaction virus/matrix but, at this day, only few data are available concerning surface properties of viruses and prediction of the adhesion capacity of one specific virus onto matrices is still very difficult.
The purpose of this study was to propose a reference system, including a representative virus surrogate, able to predict as close as possible behaviour of pathogenic viruses in term of adhesion on inert (stainless steel and polypropylene) and food surfaces (lettuce leaves, strawberries and raspberries). The adhesion of human pathogenic enteric viruses, cultivable strain of HAV and non-cultivable strains of human NoV (genogroups I and II), have been quantified and compared to these of human enteric viruses surrogates, included the MNV-1 and three F-specific RNA bacteriophages (MS2, GA and Qβ). A standardized approach was developed to assess and quantify viral adhesion on tested matrices after a contact time with each virus using real-time RT-PCR. Methods used for virus recovery were in accordance with the CEN recommendations, including a bovine Enterovirus type 1 as control to monitor the efficiency of the extraction process and amplification procedure from directly extracted or eluted samples. The adhesion of human pathogenic viruses, ranging from 0.1 to 2%, could be comparable for all matrices studied, except for NoV GII on soft fruits. Adhesion percentages obtained for the studied surrogate virus and phages were shown to be comparable to those of HAV and NoV on inert and lettuce surfaces. The MNV-1 appeared as the best candidate to simulate adhesion phenomena of all human pathogenic enteric viruses on all studied surfaces, while MS2 and GA bacteriophages could be a good alternative as model of viral adhesion on inert and lettuce surfaces. These results will be usable to design relevant experimental systems integrating adhesion behaviour of enteric viruses in the assessment of the efficiency of a technological or hygienic industrial process.
► A method was developed for the assessment of viral adhesion from different surfaces. ► The adhesion of human pathogenic enteric viruses and surrogate viruses was compared. ► The adhesion of HAV and Norovirus ranged from 0.1 to 2% on inert and vegetal matrices. ► MNV-1 appeared as the best candidate to simulate adhesion phenomena of human viruses. ► Bacteriophages could be a good model of viral adhesion on inert and lettuce surfaces.
One hundred one strains of Listeria monocytogenes isolated from seafood and cheese industry samples and from patients with listeriosis were assessed using a microtiter plate method for adhesion to ...polystyrene and stainless steel surfaces. The adhesion rate for these strains ranged from 3.10 to 35.29% with an inoculum of 8 x 10(8) cells per well. A strong correlation was found between adhesion to polystyrene and stainless steel microtiter plates, indicating that the intrinsic ability of L. monocytogenes to adhere to inert surfaces is stronger than the influence of the surface's physicochemical properties. The clinical strains were less adherent to inert surfaces than were the industrial strains. By integrating other factors such as location of the industrial strains, contamination type of the clinical strains, serotype, and pulsotype into the analysis, some weak but significant differences were noted. For the industrial isolates, the number of cells attached to both surfaces differed significantly depending on whether they were isolated from food or food-processing environments in the seafood and cheese industry. For clinical isolates, sporadic strains exhibited greater adhesion to polystyrene than did epidemic strains. Strains belonging to the pulsed-field gel electrophoretype clusters A and M (lineages II and I, respectively) were less able to adhere to polystyrene and stainless steel than were strains in the more common clusters.
► A method for the detection of influenza viruses from large mud samples was optimized. ► H5N1 viruses were detected in mud samples collected during outbreak investigation in Cambodia. ► Because of ...the lack of scientific knowledge on many aspects of the ecology and environmental properties of HPAIVs, in particular H5N1, this method will allow understanding the year-by-year perpetuation of the virus and its survival in the environment.
The role of environmental reservoirs in avian influenza virus (AIV) transmission has been investigated during AIV-associated outbreaks. To date, no method has been defined for detection of AIV from mud samples. A procedure using elution and polyethylene glycol (PEG) concentration steps was designed to detect AIV by RT-PCR from 42
g of raw mud, corresponding to 30
g of the solid fraction of mud. RNA was recovered with MagMAX AI/ND Viral RNA Isolation kit (Ambion, Austin, TX). Three elution buffers were studied and viral recoveries higher than 29% were yielded by elution with a 10% beef extract solution (pH 7). The overall method showed that, under some conditions, virus was not detectable in PEG samples, whereas viruses were detected in the elution fractions. PCR curves were improved significantly by running the amplification reaction with a mixture containing a PCR additive for inhibitor removal, such as T4 gene 32 protein (Gp32), although PCR inhibitors from mud were removed partially from PEG samples. A theoretical detection threshold of 5
×
10
5 RNA copies of H5N1 virus per 30
g of solid mud could be obtained by elution. The overall method has proved successful for detecting H5N1 virus contamination of mud specimens collected during outbreak investigations of avian influenza in Cambodia.
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