Isolation of split and whole-virion tick-borne encephalitis vaccines in an experiment and the characteristics of their immunogenic and antigenic properties

The split preparation, obtained by the treatment of purified and concentrated tick-borne encephalitis virus with 0.5% Tween-80 and ether and inactivated with formalin at a minimal concentration of 1:10,000, did not contain the active virus. After the removal of the detergent, the preparation retained its antigenic and immunogenic properties.