Cholera is as old as recorded time but amazingly, this infection is new to Haiti!
Hippocrates (2,500 years ago) wrote about an illness that was likely cholera. In the last two centuries the world has suffered 7 cholera pandemics. The seventh started in Indonesia in 1961 and the bacteria reached Haiti in the aftermath of the quake in 2010. Prior to that, cholera was one of the few plagues that had not affected Haitians in the last century.
Vibrio cholerae, the bacteria that causes cholera, can kill in hours, and in the first two years since the quake, cholera has killed more than 7,000 Haitians and infected at least another half million (5% of the population). Cholera continues to kill in Haiti and in the aftermath of the recent Hurricane Sandy, a rise in deaths due to cholera occurred.
Vibrio cholerae, courtesy Harvard Gazette.
Doctors who work in Canada do not see cholera. Cholera is a disease of poor countries and of people who do not have access to clean water and modern sanitation. Since my experience with cholera is limited, and since the disease is now common in Haiti, some research on the topic seemed appropriate.
The bacteria infects a person who ingests contaminated water or food. Person-to-person transmission or contagion from an animal or insect is not a concern. The infection rate in household contacts is about 20 to 50%, because families eat and drink the same meals. The amount of the bacteria necessary to cause disease is lower when acquired in food compared to water. The bacteria affects the cells in the first two parts of the small intestine and causes horrendous losses of salt and water in the gut, and death is usually due to shock.
There are over 200 serogroups of cholera and of these, the O1 and O139 types are the ones responsible for most of the disease. The Haiti serogroup is O1 and identical to the bacteria from Asia that is responsible for the 7th pandemic. The Haitian bacteria is thought to have arrived with Nepalese soldiers with the United Nations Peacekeeping Force. Ouch!
After a 24 to 48 hour incubation period, an infected individual develops profuse watery diarrhea that looks like "rice water." Vomiting is common. Abdominal cramps might occur. Fever is not common in adults but might be present in children.
Most individuals who are infected do not have any symptoms and most of those who do usually have a stomach flu illness that does not look much different from ordinary gastroenteritis. However, for the 5% of individuals who develop Cholera Gravis, the outcome might be fatal. In developed countries, the fatality rate is about 1%. In Haiti the fatality rate was as high as 9% at the outset in 2010 and is still as high as 4.5% in the regions outside of Port au Prince, but is now only 0.7% in the capital.
Prevention is always the best method to control any problem. However this requires clean water and modern sanitation, which sadly is not an option for the immediate future in Haiti. Only 63% of the population has access to clean water and fewer than 20% have improved sanitation (Lancet 2012). The goal is to keep contaminated poop away from water and food.
Still, good hand washing and food preparation techniques. and good water supply management can make a big difference. During an epidemic in London, England in 1854, Dr. John Snow identified water from a pump on Broad Street as the source, and removal of the pump handle contained the epidemic!
Boiling water, water purification tablets, chlorine, and ultra-violet sterilization of water are all effective. If you are boiling a crab, 8 minutes is not enough, but 10 minutes is sufficient.
Breastfeeding is protective because this limits exposure to contaminated food and water, and there might be protective antibodies present in the mother's milk.
The literally lifesaving treatment is to replace the salt and water lost from the body and to keep up with the ongoing losses until the infection runs the natural course. The body can lose 250 ml (one cup, 1/4 liter) per kg of body weight over a single 24 hours!!!
Antibiotics reduce the diarrhea and the length of time the bacteria is excreted. Low blood sugar is common and even more common in malnourished children, which is a sad fact of life in Haiti.
In about a month, I expect my limited experience with cholera will change.
Hippocrates (2,500 years ago) wrote about an illness that was likely cholera. In the last two centuries the world has suffered 7 cholera pandemics. The seventh started in Indonesia in 1961 and the bacteria reached Haiti in the aftermath of the quake in 2010. Prior to that, cholera was one of the few plagues that had not affected Haitians in the last century.
Vibrio cholerae, the bacteria that causes cholera, can kill in hours, and in the first two years since the quake, cholera has killed more than 7,000 Haitians and infected at least another half million (5% of the population). Cholera continues to kill in Haiti and in the aftermath of the recent Hurricane Sandy, a rise in deaths due to cholera occurred.
Doctors who work in Canada do not see cholera. Cholera is a disease of poor countries and of people who do not have access to clean water and modern sanitation. Since my experience with cholera is limited, and since the disease is now common in Haiti, some research on the topic seemed appropriate.
The bacteria infects a person who ingests contaminated water or food. Person-to-person transmission or contagion from an animal or insect is not a concern. The infection rate in household contacts is about 20 to 50%, because families eat and drink the same meals. The amount of the bacteria necessary to cause disease is lower when acquired in food compared to water. The bacteria affects the cells in the first two parts of the small intestine and causes horrendous losses of salt and water in the gut, and death is usually due to shock.
There are over 200 serogroups of cholera and of these, the O1 and O139 types are the ones responsible for most of the disease. The Haiti serogroup is O1 and identical to the bacteria from Asia that is responsible for the 7th pandemic. The Haitian bacteria is thought to have arrived with Nepalese soldiers with the United Nations Peacekeeping Force. Ouch!
After a 24 to 48 hour incubation period, an infected individual develops profuse watery diarrhea that looks like "rice water." Vomiting is common. Abdominal cramps might occur. Fever is not common in adults but might be present in children.
Most individuals who are infected do not have any symptoms and most of those who do usually have a stomach flu illness that does not look much different from ordinary gastroenteritis. However, for the 5% of individuals who develop Cholera Gravis, the outcome might be fatal. In developed countries, the fatality rate is about 1%. In Haiti the fatality rate was as high as 9% at the outset in 2010 and is still as high as 4.5% in the regions outside of Port au Prince, but is now only 0.7% in the capital.
Prevention is always the best method to control any problem. However this requires clean water and modern sanitation, which sadly is not an option for the immediate future in Haiti. Only 63% of the population has access to clean water and fewer than 20% have improved sanitation (Lancet 2012). The goal is to keep contaminated poop away from water and food.
Still, good hand washing and food preparation techniques. and good water supply management can make a big difference. During an epidemic in London, England in 1854, Dr. John Snow identified water from a pump on Broad Street as the source, and removal of the pump handle contained the epidemic!
Boiling water, water purification tablets, chlorine, and ultra-violet sterilization of water are all effective. If you are boiling a crab, 8 minutes is not enough, but 10 minutes is sufficient.
Breastfeeding is protective because this limits exposure to contaminated food and water, and there might be protective antibodies present in the mother's milk.
The literally lifesaving treatment is to replace the salt and water lost from the body and to keep up with the ongoing losses until the infection runs the natural course. The body can lose 250 ml (one cup, 1/4 liter) per kg of body weight over a single 24 hours!!!
Antibiotics reduce the diarrhea and the length of time the bacteria is excreted. Low blood sugar is common and even more common in malnourished children, which is a sad fact of life in Haiti.
In about a month, I expect my limited experience with cholera will change.
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