Why Cholera Is So Deadly

Earlier this month, the BBC reported that Yemen is dealing with an "unprecedented" epidemic of cholera, with more than 100,000 cases estimated by the World Health Organization. It's not something we have to worry too much about in the U.S. But in some areas, including parts of sub-Saharan Africa and India, cholera is a very real — and potentially deadly — risk.

And in parts of the world that are already dealing with years-long violent conflicts, there are additional challenges in preventing and containing outbreaks like these. In Yemen, for instance, the infrastructure that would normally provide clean drinking water and general health services aren't functioning anymore. Here's why cholera is such a problem in particular.

According to the CDC, it's an infection caused by the Vibrio cholerae bacteria, which is characterized by diarrhea. In the vast majority of cases, symptoms are mild. But up to 10% of cases can be severe, causing extreme vomiting and life-threatening dehydration.

For the most part, cholera doesn't spread directly from person to person, the CDC explains. Instead, large outbreaks are usually traced back to contaminated water and sewage as well as undercooked shellfish.

In industrialized countries, modern water treatment and sewage systems have essentially eliminated cholera, the Mayo Clinic says. But in areas without that infrastructure, the disease can spread much more easily.

If treatment for cholera is readily available, it's extremely effective. It requires antibiotics and rehydration via IV (and a specially formulated fluid). Patients may also take zinc supplements because there's evidence they can shorten the length of diarrhea related to the infection.

The major issue, of course, is that many areas of the world don't have treatment readily available. Without it, people who have severe cases of cholera can die within hours. And in areas of the world without sufficient water treatment and sewage management systems, it can spread quite easily.

"Cholera is simple to treat and prevent but while the fighting continues the task is made doubly difficult," Sajjad Mohammed Sajid, Yemen country director for international charity Oxfam, told the BBC. "A massive aid effort is needed now."