Stories tagged cholera

Cholera outbreak in Haiti is troubling

by Anonymous on Oct. 28th, 2010

Vibrio cholerae: the bacterium that causes cholera.
Vibrio cholerae: the bacterium that causes cholera.Courtesy Public domain (via Dartmouth)
An outbreak of cholera in Haiti is causing doctors and other aid workers concern. Cholera is an infection of the intestines caused by Vibrio cholerae a bacteria often found in contaminated food or drinking water. The bacteria can spread through crowded and unsanitary areas via contact with feces of infected persons. Cholera outbreaks often take place in crowded and impoverished areas, or in war zones. Symptoms include severe abdominal cramps, watery diarrhea, vomiting and rapid dehydration. Left untreated, cholera can be deadly within 24 hours. When detected, treatment involves replenishment of lost fluids and electrolytes. Improved sanitation and personal hygiene practices such as frequent hand washing can help stop the spread of the disease. So far, cholera has killed more than 300 people in Haiti, and most of the nearly 4000 recorded cases have occurred in the region of Arbonite, a rural area unaffected by the 7.0 magnitude earthquake that devastated much of the country last January. The outbreak has been slowing lately, but officials are concerned it could still spread through the hundreds of refugee tent camps located in the overcrowded capital of Port-au-Prince.

BBC story
Doctors Without Borders website
Unicef website


John Snow: Eats only vegetables, drinks only boiled water... dies of a stroke at age 41. Nuts.
John Snow: Eats only vegetables, drinks only boiled water... dies of a stroke at age 41. Nuts.Courtesy Wikimedia Commons
Here we are again, languishing in the long hours of June 17, enjoying a leisurely Snow day. A John Snow day.

Wait, you say, fractionally raising your heads from your overstuffed couches and baths full of tepid water. Didn’t John Snow actually die in June? And, like, didn’t he die on June 16, not on the 17th?

Well, yes, June 16, 1858, was in fact the day John Snow died. But I only just made up Snow day, and I wasn’t paying attention yesterday. Plus, do y’all even know who John Snow was?

Oh, John Snow was the most marvelous man! He drugged queen Victoria! He deprived thirsty communities of pump handles! He saved London from tiny invisible monsters! Oh, what a man!

John Snow was the sort of guy that posthumously gets the Cleverboots Award for Correct Thinking. Sort of like how I will surely be recognized with a Cleverboots Award years after I die, for how strikingly accurate my public ranting on the subjects of invisible lasers, lizard people, and “stay away from me, wizards!” will prove to be.

Snow was one of the first people to study the used of ether and chloroform as anesthetics. Which is to say, people had used those compounds as anesthesia before, but Snow calculated doses that would leave you somewhere between horrible pain and drugged to death. That was important. Everybody’s favorite queen of England (Victoria, duh) had Snow personally administer her anesthesia during the births of her eighth and ninth children. Once people saw Victoria doing it, everybody wanted in on anesthesia.

Snow’s greatest achievement, perhaps, came in an episode I like to call “Johnny Snow vs. Cholera.”

See, in the middle of 19th century in London, people were sort of split into three groups. There was the “Cholera is caused by poisonous gases” group. Most everybody thought that theory was the best, and it was called the “miasma theory.” There was also the “Cholera is caused by something tiny or invisible in water” group. This was pretty much what we call “germ theory,” and most everybody was all, “Germs? That’s stupid. Check your head!” And, finally, there was the “Hey, we’re actually dying of cholera over here” group, and most everybody thought they were gross.

But not John Snow! Instead of arguing and making up theories based on what seemed reasonable, he actually went out and looked at stuff. Gasp!

Without knowing for certain exactly how cholera was being transmitted (germs or miasma, or whatever), Snow began to record who in London was getting the disease, and he plotted cases on city street maps. He saw clusters of the disease in certain areas of the map, and so he looked for common elements. In the case of one outbreak, Snow realized that the majority of infected people were getting their water from one of two water companies, both of which were pulling water from a dirty (read: full of sewage) section of the Thames river. In another outbreak, Snow found that most of the victims of the disease were getting their water from a particular public pump. When John Snow had the handle of the pump removed, so that nobody could get water from anymore, the outbreak ended.

Snow’s discoveries from studying the cholera outbreaks added to the evidence for germ theory, and, perhaps more importantly, constituted a huge stride forward in the science of epidemiology. Snow wasn’t just figuring out how to cure diseases, he was tracking down where they start, and learning about how they move through populations. These are the same basic principles behind the actions health organizations still take today when dealing with outbreaks in the much larger population pools (or pool) of the 21st century.

It’s pretty interesting stuff. Check out this Snow-stravaganza: UCLA’s comprehensive page on John Snow and the cholera outbreaks.

Now enjoy what’s left of your Snow day.

Government officials in Zimbabwe have (finally) declared a state of emergency in the cholera epidemic that has already sickened more than 12,000 people and killed more than 550. Caused by the Vibrio cholerae bacterium, cholera's hallmarks are massive watery diarrhea and vomiting, and people who die from cholera generally die from dehydration. It's a terrible cycle: people get cholera from a contaminated water supply (or food that's been tainted through contaminated water. They don't have clean water to drink, so have no means of safe rehydration, and they don't have safe sewage systems, so waste infected with the cholera bacteria goes right back into the water where it can infect others.

Cholera is rare in the developed world today, but it wasn't always. For a fascinating real-life epidemiological detective story about the deadliest cholera outbreak in London's history (in August, 1854), check out Steven Johnson's "The Ghost Map." Even if you're not into non-fiction, it's a great read. I couldn't put it down.

If you are interested in learning more about cholera go to Science Museum of Minnesota's Disease Detectives website and explore cholera and four other important diseases through time. Cholera is also highlighted in a New-York Historical Society exhibition called PLAGUE in GOTHAM! Cholera in Nineteenth-Century New York. Click here to read an article about the exhibition in the New York Times.

Researchers in Japan have developed a strain of rice that, when ground into a powder, acts as a vaccine for cholera. The rice has been modified to trick the body into producing an immune response, thus leaving you protected if you later encounter the bacteria.

The rice has only been tested in mice so far. If it work in human trials, it may be a major advance in the fight against cholera, as the rice powder can be stored more easily than the current vaccine.