Inactivation of Hepatitis a Virus by Heat and Formaldehyde

The GBM strain of hepatitis A virus adapted to a fetal rhesus monkey kidney cell line (Frhk-4/R) was treated and inactivated at several different temperatures and with several different formaldehyde concentrations. Heat inactivation showed that no inactivation occurred after treatment for 60 minutes at 37°C. Treatment for 60 minutes at 50°C reduced infectivity by 1 log 10 step ; treatment for 60 minutes at 60°C, by 4 log 10 steps. Treatment for 30 minutes at 70°C resulted in complete inactivation of HAV. Complete inactivation by formaldehyde treatment was achieved only with a 0.35% concentration. Treatment with lower concentrations resulted in incomplete HAV inactivation.