Provide historic milestones in epidemiology in which diseases were controlled using research methods, even before science had caught up with identifying the responsible agent.

What will be an ideal response?

Edward Jenner (1749-1823) developed a vaccine against smallpox using cow pox 160 years before the virus was identified.  John Snow (1813-1858) described the association between dirty water and cholera 44 years before the suspect bacterium, Vibrio cholerae was identified.  Ignaz Semmelweis (1818-1865) described the association between childbed fever, a life-threatening infection contracted by a woman during or shortly after childbirth, and physician's unclean hands 32 years before a causal agent was discovered.  James Lind (1716-1794) conducted an experiment which showed that scurvy, a disease common among sailors on long voyages with no fresh fruits or vegetables, could be treated and prevented with limes, lemons, and oranges 175 years before ascorbic acid was discovered.  In 1915, Joseph Goldberger (1874-1927) proved that pellagra, a disease characterized by diarrhea, dermatitis, dementia and death, was not infectious but nutritional in origin and could be prevented by increasing the amount of animal products in the diet and by substituting oatmeal for corn grits.  This finding occurred 10 years before the cause of pellagra, vitamin B3, was discovered.