Further studies on thermal resistance of bovine parvovirus against moist and dry heat.

To supplement the results of thermal resistance of bovine parvovirus (Haden strain, BPV) published previously, we carried out assays at 60 degrees C (moist heat) to compare the thermal resistance of BPV with that of hepatitis B-virus (HBV). What we know about the resistance of HBV at a temperature of 60 degrees C is mainly based on data collected within the context of blood product pasteurization. The results suggest that at a temperature of 60 degrees C, BPV shows thermal resistance comparable to HBV. Thus, BPV--which is easier to handle--can be considered a good test virus to verify the efficacy of thermal disinfection techniques against HBV. BPV is very resistant against dry heat of 100 degrees C, the inactivation largely depending upon the residual moisture of the lyophilisate. Reducing the residual moisture from 2% to less than 1%, the exposure time has to be prolonged by ca. 2.5 times to achieve the same virucidal effect.