Rudolf Weigl (1883–1957) — developer of a vaccine against typhoid fever (spotted fever). He used lice infected with typhoid fever for his research. He also conducted observations on his own body, when he contracted the disease during his work. The vaccine invented by Weigl was initially introduced in Poland, but soon began to be used throughout the world, helping to significantly reduce the incidence of the disease and prevent epidemics. He was nominated for the Nobel Prize four times, and was given the title of Righteous Among the Nations.