Man stands in lab looking at microscope

This 'bacteria hunter' discovered the causes of tuberculosis, anthrax, and cholera

Robert Koch, a founding father of microbiology, used hands-on experiments in the 1800s to find the bacteria behind three of history's deadliest diseases.

Robert Koch peers into a microscope in his laboratory around 1900.
SÜDDEUTSCHE ZEITUNG PHOTO/AGE FOTOSTOCK
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