The World Health Organization hopes to reduce the number of cholera cases and deaths with a combination of oral cholera vaccines and conventional control methods.

In spite of an estimated 3 million to 5 million cases of cholera each year in the world, officials at the World Health Organization (WHO) are confident this potentially deadly disease can be controlled.

The fight against cholera relies upon a careful combination of two oral cholera vaccines alongside conventional control measures such as planning earlier for cholera outbreaks, teaching people about the signs of the disease, and improving public hygiene.

The WHO has already rolled out vaccination programs in South Sudan and Tanzania, two areas where security problems and displacement of people from their homes have fueled cholera outbreaks. In addition, the WHO has been working with governments and other partner organizations to prepare for potential cholera outbreaks in conflict-torn Yemen and earthquake-ravaged Nepal.

Cholera is an acute intestinal infection caused by a bacterium that can be picked up through contaminated water and food. According to the WHO, each year cholera kills an estimated 100,000 to 120,000 people worldwide.

Once ingested, the bacterium produces a toxin that causes the intestines to produce a large amount of watery diarrhea. Some people also experience vomiting. This can cause severe dehydration. Left untreated, cholera can lead to death in as little as a few hours.

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As part of its efforts to fight cholera, the WHO has been stockpiling oral cholera vaccines. Since the start of this effort in 2013, health officials have distributed almost 2 million doses of the vaccine. This is the same amount that was used in the 15 years prior to that time.

The global stockpile is funded by the Bill and Melinda Gates Foundation, the USAID Office of Foreign Disaster Assistance, and other humanitarian organizations.

According to the WHO, the increased stockpiling has helped stop new cholera outbreaks in their tracks.

In South Sudan, thousands of displaced people were forced to take shelter in makeshift camps at United Nations sites. These types of camps are at high risk of cholera outbreaks due to poor hygiene and sanitary procedures. Once an outbreak starts in a camp, it also can easily spread to surrounding areas.

In 2014, the WHO and its partner organizations distributed the oral cholera vaccine to people in the camps before an outbreak occurred. This reduced the number of illnesses and deaths in the high-risk camp population.

Oral cholera vaccines have also been successful in slowing outbreaks in other areas of South Sudan. After a vaccination campaign in vulnerable areas in 2015, only 523 cases of cholera were reported by July 1. This included 29 deaths.

During the previous year, before pre-emptive measures against cholera outbreaks, the same areas reported 2,540 cholera cases, with 59 deaths.

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Heading off cholera outbreaks in South Sudan, and other areas of the world, requires vaccines to be used alongside conventional control measures.

This includes updating national and local plans for dealing with cholera before an outbreak occurs. In addition, rapid response teams need to be trained and supplies distributed early so they are available when needed.

Identifying the disease when it occurs is also essential. For that, the WHO and its partner organizations distribute diagnostic test kits throughout a country to enable a prompt response when suspected cases appear.

A large part of the response against cholera, though, involves educating the public about the disease. In South Sudan, traditional media outlets, such as radio, have raised awareness about cholera.

Educators also went door-to-door, telling people about the disease, how it spreads, and the signs to look for. These efforts can help people act more quickly if they suspect someone they know has become ill.

If identified early, cholera can be easily treated through the use of oral rehydration salts to counteract the effects of diarrhea. In severe cases, people may require intravenous fluids.

The WHO hopes that by expanding this kind of coordinated effort — along with the use of oral cholera vaccines — to other at-risk areas in the world, they can reduce the number of cases and deaths worldwide.

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