Cholera is a disease caused by the cholera bacterium (vibrio cholerae), which infects humans usually by ingestion of contaminated drinking water. The disease is still existent in the world today, but thanks to advances in scientific understanding and increased hygiene people in the western world are less likely to get cholera.
If untreated, cholera is a truly atrocious disease and it can advance within hours to cause death. It starts suddenly and quickly causes dangerous fluid loss. Symptoms of cholera infection include diarrhoea, characterized by a milky appearance known as ‘rice-water stool’. In addition, persistent painful vomiting occurs. Dehydration develops within hours after the onset of symptoms, and can be mild or severe depending on the amount of fluid lost. This can cause lethargy, sunken eyes, shrivelled skin, low blood pressure and irregular heartbeat. Cholera also causes a characteristic blue tinge to the nails and skin.
It is this dehydration that is most dangerous: it can lead to a rapid loss of minerals in the blood, which are known as electrolytes. These maintain the balance of bodily fluids. Sudden loss of electrolytes leads to muscle cramps and shock, and can lead to death in a matter of hours, even in people who were healthy beforehand.
Cholera is better understood and easily treated today. The severe dehydration that can lead to death can now be prevented with a simple rehydration electrolyte solution easily available in the western world.
Although modern sewage and water treatment have eradicated cholera in industrialized countries, cholera has not fully gone away. The disease is still in poorer countries in Africa and Southeast Asia. Outbreaks of cholera may still occur today, anywhere circumstances such as war or natural disasters force people to live in crowded conditions without satisfactory sanitation.
Illustration below: Microscopic image of the cholera bacterium.