|Guidelines for Cholera Control (WHO - OMS, 1993, 68 p.)|
At the start of a cholera outbreak, even as general control measures are applied, epidemiological studies can determine the magnitude of the outbreak and the mode of transmission, so that more specific and effective control measures can be applied. Recording the time and place of suspected and confirmed cases, preferably on a spot map, can help identify sources and routes of infection.
Case-control studies, although difficult to conduct and interpret, may help to define the mode of transmission, particularly in newly affected areas. Countries may request assistance from WHO or other outside sources to conduct them. Laboratory analysis of samples of suspect water, sewage, and food may also be helpful.
During cholera outbreaks in newly affected areas, people of all ages may contract the disease. However, the more mobile members of the community (usually adults) are more frequently affected because of their greater exposure to possible sources of contamination, such as food or drinks taken outside the home. In contrast, a preponderance of cases in children suggests that the disease is endemic in the area.