[Determination of virucidal activity. Value of the bacteriophage as a viral model]

Virucidal activity of six disinfectants was determined in vitro against bacteriophages T2, MS2 and phiX 174. The preliminary study shows the simplifications resulting from the use of bacteriophages for this kind of test: easy and reproducible production of stores of bacteriophages with controlled purity, good stability and concentration of at least 10(7) PFU/ml, and no limitation due to cytotoxicity. Virucidal concentrations determined for a 15-minute contact are 31.2 ppm (active chlorine) for hypochlorite solution, 10 ppm (iodine) for an iodophor, 1% for formaline, 0.5% for glutaraldehyde, more than 0.3% for a quaternary ammonium salt and more than 3% for an amphotere. The proposed method gives practical information for decontamination in bio-industry. Given the resistance noted with bacteriophages, this experimental method could be applied in a more general setting.