Robert Koch was a German physician that’s considered one of the primary founders of microbiology- setting the foundation for loads of public health interventions that have drastically improved our quality of life. He was the first scientist to verify the Germ Theory of Disease (in 1876) by showing that anthrax is caused by a bacteria (the previous theory was that disease was spread by “bad air”). Koch later discovered that bacteria cause tuberculosis and cholera.
He went on to develop what became known as “Koch’s Postulates” – which consist of 4 criteria that establish a causal relationship between a microbe and disease. These principles led to large advances in identifying the organisms that were responsible for major public health issues at the time- diptheria, typhoid, pneumonia, gonorrhea, leprosy, plague, tetanus, and syphilis.
His most important work was with tuberculosis (called consumption at the time). Between 1700 and 1900 TB is thought to have caused nearly 1 billion deaths. Koch’s discovery that the TB was caused by a bacteria led to public health interventions that helped limit the spread of TB… and eventually led to the development of medications to kill the bacteria. You can read more about his story on the Official Website of the Nobel Prize.