Which scientist proposed postulates to establish the causation of disease and identified the anthrax agent?

• A. Robert Koch
• B. John Snow
• C. Florence Nightingale
• D. Louis Pasteur

Answer: (A)

Identifying a causal relationship between a microbe and disease through a formal framework, and pinpointing the exact organism responsible. Robert Koch developed Koch's postulates, a practical set of steps used to demonstrate that a specific microbe causes a disease: the microbe must be found in every case of the disease and not in healthy individuals, it must be isolated in pure culture, it should cause disease when introduced into a healthy host, and it must be re-isolated from the newly diseased host. He also identified Bacillus anthracis as the agent of anthrax, providing the concrete link between a microbe and a disease. While John Snow traced cholera to contaminated water and Florence Nightingale advanced hospital sanitation and public health, or Louis Pasteur contributed to germ theory and vaccines, none of them both proposed the postulates and identified the anthrax organism.