Cholera is an infection that affects the intestines. Symptoms range from none, to mild, to severe and can include diarrhea, vomiting, and stomach cramps, beginning two to five days after exposure. It’s caused by unclean or infected water, uncooked seafood, poor sanitation, and more. It’s more likely found in impoverished areas of the world. All around, it’s a pretty bad infection to get. Though there have been vaccines for it floating around since the early 90s, none have been as effective or cheap as the one introduced recently in Bangladesh.

The trial was conducted in Bangladesh’s capital city of Dhaka. As many as 300,000 people in the city are infected by cholera, but this cheap vaccine has been shown to be effective in one form or another in more than 260,000 people.

The experiment split up the participants into three groups: The first group got just the vaccine and were sent on their way; the second group got the vaccine and were given chlorine-treated water to drink, and told to wash their hands with soap more often; the third group didn’t get anything.

The researchers then wait two years to tally up their results. In the vaccine-only group, they found that there were 37 percent fewer cases of cholera outbreak. In the vaccine, water and hand-washing group, 45 percent less outbreaks were reported. Out of the most severe, death-causing cases, there was a 53 percent decrease in the first group and a 57 percent decrease in the second group.

The vaccine, called Shanchol and developed by the International Vaccine Institute in 2009, was funded by the Bill and Melinda Gates Foundation. The two vaccine doses required cost less than $4 total.

Cholera is certainly an epidemic in most third-world countries, but it is definitely an under-reported one. According to reports from 2011 by the World Health Organization (WHO), there were nearly 600,000 cases and 8,000 deaths reported in 58 countries. However, many countries do not disclose all the information regarding cholera, as that might induce travel and trade sanctions. It’s estimated that global cholera numbers are closer to five million cases and 200,000 deaths. That’s a staggering change from what WHO reported.

It’s still inspiring to see that a cheap, effective vaccine can be mass produced and marketed to the places that it is needed most. But, as many experts agree, the key to stopping cholera in its tracks is clean water, proper sanitation, and routine checkups. For now, however, a vaccine will have to do.