[2 methods of studying in vitro the virucidal action of disinfectants]

The assessment of the virucidal activity of disinfectants and antiseptics is a permanent care. That is why, in recent years, studies have been developed in order to standardize these techniques. The present work describes two methods, the method of instantaneous dilution and that of gel filtration. The kinetics of inactivation of two viruses (the Talfan and the Canine Contagious Hepatitis viruses) which were obtained after contact with 10 disinfectants commonly used in agriculture and the food industry are compared. Usually these products exhibit a weak virucidal activity at the dosages recommended by the manufacturer. The present study emphasizes the necessity to have available viruses with a high titer and the inconvenience of using only the gel filtration technique when a precipitation takes place between the disinfectant and the viral suspension.