THE EFFECT OF ULTRAVIOLET-IRRADIATION, HEAT, PH, OZONE, SALINITY AND CHEMICAL DISINFECTANTS ON THE INFECTIVITY OF WHITE SPOT SYNDROME BACULOVIRUS

The virucidal effects of ultraviolet (UV) irradiation, heat, pH, ozone , salinity and some chemical disinfectants on white spot syndrome bacu lovirus (WSBV) were investigated by infectivity assay using juvenile b lack tiger prawn, Penaeus monodon. WSBV became completely non-infectio us after 60 min UV irradiation (9 x 10(5) mu W s/cm(2)). WSBV was rend ered non-infectious by 55 degrees C and 70 degrees C heat treatment wi thin 90 min and 5 min, respectively. WSBV was also completely inactiva ted by high acidity, pH 1 for 10 min, pH 3 for 1 h and by high alkalin ity, pH 12 for 10 min at RT (25 degrees C). The effective concentratio n for ozone to reduce WSBVs infectivity to zero was 0.5 mu g/ml as a t otal residual oxidant for 10 min at RT. WSBV was inactivated by contac t for 10 min at RT with a final concentration of 100 ppm of sodium hyp ochlorite and povidone iodine and 75 ppm of benzalkonium chloride. Sod ium chloride in concentrations ranging from 0-10% had no virucidal eff ect on the infectivity of WSBV. (C) 1998 Published by Elsevier Science B.V. All rights reserved.