北里柴三郎
Sahachiro Hata researched bubonic plague with Japanese bacteriologist and physician, Kitasato Shibasaburō, who co-discovered the infectious agent, a bacterium called "Yersinia pestis." Hata worked as an assistant for Kitasato and conducted research into the prevention of plague and other epidemic diseases. Hata helped formulate the "Communicable Disease Prevention Law," which was enacted in 1897 as the first legal framework for disease control in Japan.