Efficacy of Egg Disinfection by Povidone-Iodine Solutions for Inactivation of Causative Agent of Bacterial Kidney Disease in vitro

Abstract

Effect of povidone-iodine (PVI) treatment on the viability of Renibacterium salmoninarum, the causative agent of bacterial kidney disease (BKD) was investigated in vitro. ​A novel dilution plating for Tok46 strain revealed that WOAH's shortest recommended treatment for hardened eggs (100 ppm available iodine for 10 min) achieved 4.6-log reduction in the colony-forming units. ​Treatment with higher concentrations of available iodine achieved further reduction. ​The effectiveness at 100 ppm was validated across two additional strains by turbidity measurements. ​The disinfection using the conventional procedures likely reduces transmission risk of BKD while those with higher concentration of PVI will be more effective.