Cholera has been a plague on human societies for thousands of years. The pathogens ability to exist in water, essential to human life, has prolonged its ability to find human hosts and continue to have an impact on human society. Over the past two centuries there have been seven separate cholera pandemics that have devastated human societies. While endemic to India, after colonization by the British trade ships began to spread the disease to Europe and the rest of the world. After the disease began to ravage Europe in the mid-1800s, Irish immigration to the United States due to the potatoes famine also spread cholera to North America. Poor living conditions and lack of access to clean water I poorer neighborhoods spread cholera throughout the population of large cities.
During the third great cholera pandemic several British scientists began conducting research in an effort to discover what exactly what caused cholera and how to overcome it. John Snow determined that cholera was the result of poor water and used what was called “shoe leather epidemiology” the actual going out and finding of cases, to determine exactly which water sources were infected with cholera. Henry Whitehead assisted Snow with this type of epidemiology by aiding him in understanding the population he was examining and was able to determine exactly how the epidemic started. Around the same time, Italian doctor Filippo Pacini correctly determined that the cholera bacterium was the cause of the disease. However, Pacini did not receive credit for his discovery until years later. Independently, Robert Koch was able to determine that Vibrio cholera as the causative agent of disease.
Recently, in Yemen, warfare has caused a breakdown of traditional public health infrastructure, a large portion of which is access to clean water. Without it, thousands have died.
In Haiti, an already poor country, a devastating earthquake killed hundreds of thousands of people and destroyed what little public health infrastructure there was. Massive refugee camps were formed to help aid workers care for the homeless, but these camps had poor access to clean water and cholera began to spread throughout the camps. In addition, Haiti’s Bayakou men haul away human excrement by hand, spreading cholera infected feces to their families and spreading it throughout the population.