A technology of preparing hepatitis A virus (HAV) from human stools.

Two-step differential centrifugation through 40% and 20% sucrose of 20% water extracts of HAV-positive stools yielded specific defined antigens for hepatitis A serological diagnosis by 3rd-generation methods. The antigens would be suitable also for other purposes. Products of comparable quality were obtained from HAV-positive stools yielding different amounts of virus. Optimal were incubation-period stools, where the loss in HAV yield was minimal; these preparations displayed the highest antigenic capacity and could be diluted up to 150 fold for serological reactions. Results obtained in extensive preliminary experiments, outlined in the Discussion, corroborated the advantages and efficiency of the proposed technology.