Operating conditions for using oiled sodocalcic glass wool (Saint Gobain R. 725) to concentrate enteroviruses in 100 to 1000 liters samples were determined. These filters recovered from 62 to 75% of several enteroviruses (laboratory strains or field isolates) and rotavirus SA11 that were added to tap water. The technique permitted the recovery of 62% and 57% of poliovirus added respectively to river water and treated waste water. The results of a 44 months survey of the Seine and Mame river waters are reported. Being efficient at ambient pH, the use of glass wool may permit continuous virological monitoring of water samples.

We describe an analytical protocol to study biofilms that develop inside silicone tubing of dialysis machines. This protocol has been set up with the help of a dynamic testing device reproducing dialysis conditions. The methodology includes direct microscopic observation, biofilm removal with an original mechanical biofilm scraper, quantitative analysis with culturable and total bacteria counting, and endotoxin level measurement using the LAL chromogenic kinetic assay. The analytical protocol has been assessed on 13 different clinical tubing samples. Most samples were contaminated by adherent cells and the thickest biofilms were found at the connection between the dialysis water distribution loop and the dialysis machine. The less contaminated samples had been removed from dialysis machines that were decontaminated with citric acid and autoclaving, showing the importance of the decontamination procedure for the prevention of biofilm development. This article shows that easy, rapid, reproducible, and economical methods are applicable for a routine analysis of biofilms that develop on dialysis systems and should be included in the regular control of the microbiological quality of dialysis liquids.

No abstract

This study was initiated by the AFNOR water microbiology working group to evaluate the performance of the glass wool method for virus recovery. Its reliability was tested with drinking and sea water by respectively nine and thirteen laboratories. In both trials, six were actively involved in water virology research, one was designated as a central laboratory, the others had no experience in virological practices. Analysis of reproducibility and repeatability according to NF-ISO 5725-2 were realized. For drinking waters (24 assays), the average recovery efficiency was 72%, mean standard deviations: repeatability 12.4%; reproducibility 33.6%; inter-laboratories 21%. For sea waters (39 assays), the average recovery efficiency was 75% and the mean standard deviations 6.9%, 17.9% and 11% respectively.

Investigations were undertaken on the antiviral action of an hydroalcoholic extract from Haemanthus albijlos bulb, reported here as an efficient agent against RNA viruses. Poliovirus propagated on HeLa cells with different concentrations of the extract was used in the assays. The effect on cellular RNA, DNA and protein synthesis as well as on viral RNA synthesis was evaluated by measuring the radioactivity incorporated using labelled precursors.A 0.2 pL/mL concentration of the plant extract showed an inhibition of cellular RNA, DNA and protein synthesis compared with the control of 44%, 40% and 52%, respectively. At the same concentration a 90% decrease of the viral RNA synthesis was observed over 210 min.