CXC CSEC Human and Social Biology: Disease and its impact on humans: Cholera
CXC CSEC Human and Social Biology:
Disease and its impact on humans: Cholera
What is cholera?
Cholera is an acute intestinal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae.
How is cholera spread?
The cholera germ is passed in the stool. It is spread by eating or drinking food or water contaminated by the fecal waste of an infected person.
What are the symptoms of cholera?
Cholera produces an enterotoxin that causes a copious, painless, watery diarrhoea that can quickly lead to severe dehydration and death if treatment is not promptly given. Vomiting also occurs in most patients. Fever is usually absent.
About 75% of people infected with V. cholerae do not develop any symptoms, although the bacteria are present in their faeces for 7–14 days after infection and are shed back into the environment, potentially infecting other people.
Among people who develop symptoms, 80% have mild to moderate diarrhoea and dehydration, while around 20% develop acute watery diarrhoea with severe dehydration. This can lead to death if untreated.
What is the treatment for cholera?
Because of the rapid dehydration that may result from severe diarrhea, replacement of fluids by mouth or by the intravenous route is critical. Up to 80% of cases can be successfully treated with oral rehydration salts.
Antibiotics, such as tetracycline, are also used to shorten the duration of diarrhea and shedding of the germs in the feces.
What are the environmental risks for cholera?
Cholera transmission is closely linked to inadequate environmental management. Typical at-risk areas include peri-urban slums, where basic infrastructure is not available, as well as camps for internally displaced people or refugees, where minimum requirements of clean water and sanitation are not met.
Disasters such as hurricanes or earthquakes which result in disruptions to water and sanitation systems, or the displacement of populations to inadequate and overcrowded camps can increase the risk of cholera transmission should the bacteria be present or introduced. Epidemics have never arisen from dead bodies.
Cholera is a high risk factor when populations have difficulty in accessing safe drinking water and adequate sanitation facilities
What are the preventative measures against cholera?
Provision of safe water and sanitation is critical in reducing the impact of cholera and other waterborne diseases.
Once a cholera outbreak is identified, the primary intervention strategy is to reduce deaths by ensuring prompt access to treatment, and to control the spread of the disease by providing community access to safe water, proper sanitation and health education. This is done to improve the hygiene and safe food handling practices of the community. The provision of access to safe water and sanitation is usually a great challenge but remains the critical factor in reducing the impact of cholera.
Oral cholera vaccines are considered an additional means to control cholera, but should not replace conventional control measures.
Cholera in the Caribbean: the case of Haiti
Clip couresy UNICEF televison