Cholera epidemiology

Swerdlow, D., Malenga, G., Begkoyian, G., Nyangulu, D., Toole, M., Waldman, R., et al. (1997). Epidemic cholera among refugees in Malawi, Africa Treatment and transmission. Epidemiology and Infection, 118(3), 207-214. 

Epidemiology can therefore show an association between disease and another factor such as location, but it does not give the exact cause. Snow did not discover the cause of cholera, which Robert Koch, a German physician, did later in the century. Koch showed that cholera was caused by bacteria, using experimentation. He produced a set of criteria, known as Koch s postulates , describing the necessary experimental procedure. His postulates can be roughly adapted to suit the situation with regard to disease caused by chemicals (see box). 

Petrera, M. and Montoya, M. 1992. The economic impact of the cholera epidemic, Peru, 1991. Epidemiological Bulliten, PAHO 13 9-12. 

Faruque SM, Albert MJ, Mekalanos JJ. Epidemiology, genetics, and ecology of toxigenic Vibrio cholerae. Microbiol Mol Bio Rev 1998 64 1301-1314. 

Epidemiologically, cholera tends to occur in two patterns it spreads in pandemic form, moving across continents, and, after introduction into an area, it may settle into an endemic pattern marked by seasonal epidemics. From the perspective of under-tanding emergence of pathogens, this leads to two basic questions what mechanisms underlie occurrence of pandemic disease, and, once the pandemic wave has passed, what are the triggers for recurrent seasonal epidemics ... 

Historically, epidemiology was the study of epidemics. One of the earliest studies was British physician John Snow s identification of contaminated water from the Thames River as the source of cholera during 1853-1854. This led to the eradication of cholera... 

Historically, epidemiology originated in relation to the study of the great epidemic diseases such as cholera, bubonic plague, (often referred to as Black Death in the Middle Ages) smallpox, yellow fever and typhus. These disease were associated with high mortality and, until the twentieth century, were the most important threats to life. 

Several historical events—cholera in London, clinical study in Paris, and measles in the Faeroe Islands—are considered milestones in the develop)-ment of epidemiologic studies. 

In 1854, a cholera epidemic struck the Soho district of London. Physician John Snow traced the source of the disease to contaminated water being delivered through public pumps. His investigative methods led to the science of epidemiology. 

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