Simha was the maintenance manager of the Jewish Hospital in Budapest on 3, Szabolcs Street. After Austria was annexed by Germany, many Jews who did not have Austrian citizenship were deported. Some of them were put on a ship that sailed on the Danube River in the direction of the international border of three countries. The refugees did not receive any food or water. 300 refugees came off the ship and found refuge in a hospital until the end of the war.
After the Germans invaded Slovakia many refugees were taken to the hospital out of concern for their welfare. Simha Vajda was in charge of their employment and financial maintenance. He helped the refugees in all ways to enable them to survive the wartime years.
Simha Vajda made aliya. He worked for Solel Boneh. Later he lived in a home for the elderly in Natanya.