Describe an example of a historical situation where the work of many people over time helped solve a human health problem.
It is rare today that a lone scientist working alone in a laboratory will make a break-through discovery which will revolutionize health care. More likely, multiple scientist working in multiple laboratories following multiple avenues will come together to formulate a cure. A great example is the polio vaccine. Today we have two vaccines, the killed (inactivated) Salk vaccine, and live attenuated Sabin vaccine (oral polio vaccine). The Salk vaccine, successfully tested in 1955, could not have been developed without prior experimental results, including, but not limited to: 1) the Enders, Weller, and Robbins demonstration that poliovirus need not be grown in animals but could be grown in culture; 2) the Brodian and Morgan discovery that there are 3 different serotypes of the virus and immunity to one does not confer immunity to the other -- this means the vaccine must be composed of 3 virus serotypes. Likewise the Sabin vaccine would not be developed without multiple prior experimental results. Notable is the work by Theiler and Koprowski, who showed the virus could be attenuated by passage in non-human tissue culture cells or at sub-physiological temperatures. By 1979, widespread transmission of poliovirus was eliminated from the US (the US was declared poliovirus free). However, sporadic, isolated cases of disease still occur in unvaccinated individuals.
In 1988, the World Health Assemble resolved to eradicate polio virus. Again multiple researchers, corporations, foundations, and countries came together to initiated this endeavor. Since that time, the Sabin vaccine has been administered to millions of children, resulting in active transmission in only Afghanistan and Pakistan.
Today researchers are still working on improving the polio vaccine, using techniques of molecular biology, better understanding of virus replication, and more thorough knowledge of immunity.