Evaluation of chlorine dioxide in liquid state and in gaseous state as virucidal agent against avian influenza virus and infectious bronchitis virus.

The antiviral activity of chlorine dioxide (ClO) in liquid (ClO gas dissolved liquid) and gaseous state against avian influenza virus (AIV) and infectious bronchitis virus (IBV) was evaluated. To evaluate the effect of ClO in liquid state, suspension tests (10 ppm) and carrier tests in dropping / wiping techniques (100 ppm) were performed. In the suspension test, virus titers were reduced below the detection limit within 15 sec after treatment, in spite of the presence of an accompanying organic matter. In the carrier test by dropping technique, AIV and IBV were reduced to below the detection limit in 1 and 3 min, respectively. Following wiping technique, no virus was detected in the wiping sheets after 30 sec of reaction. Both viruses adhering to the carriers were also reduced by 3 logs, thereby indicating that they were effectively inactivated. In addition, the effect of ClO gas against IBV in aerosols was evaluated. After the exposure of sprayed IBV to ClO gas for a few seconds, 94.2% reduction of the virus titer was observed, as compared to the pre-treatment control. Altogether, hence, ClO has an evident potential to be an effective disinfectant for the prevention and control of AIV and IBV infections on poultry farms.