The World Health Organization is sending 900,000 doses of cholera vaccine to Bangladesh to help prevent a major outbreak of cholera in the crowded Rohingya refugee camp that sits on the border of Bangladesh and Myanmar. At least a half-million Rohingya, a Muslim minority in Myanmar, have crossed the border to escape a military crackdown in their villages. In Yemen, a massive and deadly cholera epidemic has affected a half-million people, and the World Health Organization expects that number to climb to 1 million by year’s end. Worldwide, about 100,000 people die from cholera each year. WATCH: WHO, Others Pledge to End Cholera End cholera by 2030 On Tuesday, the WHO, along with governments, aid agencies and donors announced a roadmap to end cholera by 2030. It’s the first global pledge to end this disease. Dr. Amesh Adalja said it’s not possible to eliminate cholera because cholera is a bacteria that exists naturally. Adalja is an infectious disease expert at the Johns Hopkins University Center for Health Security. He is also a fellow of the Infectious Diseases Society of America. Adalja told VOA it is possible to make cholera as rare in Bangladesh and in Yemen as it is in the United States and the rest of North America. He said sanitation is the key to eliminating cholera. The disease is “not something that should happen in 2017,” Adalja said. “This is something that can be fixed by development and the civilizing effect of sanitation.” Cholera is a diarrheal disease. The bacteria that causes cholera lives in coastal waters and in brackish rivers. It thrives where there is poor water treatment, poor toilet sanitation and poor hygiene. It’s caused by eating or drinking contaminated food and water. Malnutrition plays a role Malnutrition is also a factor. Jesse Hartness is the senior director of emergency health and nutrition at Save the Children, an agency that has been working to control the cholera outbreak in Yemen. “There’s a cycle of illness and malnutrition where you have a child who is sick, and they lose their appetite,” Hartness said. “They are dehydrated from having diarrhea, they lose weight, and, once they are malnourished, that also drives their vulnerability to additional illness.” Anyone can get cholera, but children, pregnant women and the elderly are most at risk. Yet, cholera is not difficult or expensive to treat. Hartness said it is simple if the disease is caught early and if you can provide hydration to the less severe patients so they don’t become severe patients who require more intensive treatment. But in places ravaged by flooding and other natural disasters, or by manmade disasters like war, or in crowded refugee camps, sanitation is hard to maintain. Water can’t be treated properly. Human waste can’t easily be disposed of hygienically, so in addition to providing aid, organizations like Save the Children find themselves trying to rebuild sanitation systems. The WHO says about 2 billion people globally lack access to clean water. Vaccine available Vaccines can help. Adalja said the oral vaccines the WHO uses to manage cholera outbreaks have about a 65 percent effectiveness rate over five years. He adds that “65 percent isn’t 100 percent, but it is very good.” Hartness said in order to end cholera in Yemen, the war that Yemen has been mired in for three years has to end. “In order to really look at ending this outbreak, we have to look at ending the war,” he said. “And if that can’t happen immediately, we have to look at negotiating access to these communities … that are the hardest to reach.” Adalja added, “It’s basically a poverty trap for some of those countries which they can never get out of. … This is something that can be fixed by development and the civilizing effect of sanitation.” Forty-seven countries are affected by cholera, and the WHO expects the global cholera situation to get worse, which is behind its urgency to end the disease.