Yefim Blok was born to Isaak and Genya. Prior to WWII he lived in Yessentuki, Russia (USSR). During the war he was in Yessentuki, Russia (USSR). Yefim survived the Shoah.
Jews deported to or imprisoned in camps, ghettos or forced labor frameworks, who were in hiding, in clandestinity or resistance formations, or suffered relentless persecution under antisemitic legislation in territories controlled by the Nazis or their allies, and were alive by the end of 1945 are considered Shoah survivors.