During the month of March, 2019, the southern hemisphere experienced one of its worst tropical storms in recorded history. Cyclone Idai slammed into the east coast of Africa, striking deep into the continent and leaving hundreds dead and hundreds of thousands severely affected by flooding and destroyed infrastructure. Madagascar, Malawi, Mozambique and Zimbabwe were all impacted, and now we have word that a cholera epidemic has started in Mozambique due to the lack of potable water and sanitation.
Om response, the World Health Organization (WHO) and relief agencies have started a cholera vaccination drive to reach all of the people at risk. According to WHO:
“The 884 953 doses of oral cholera vaccine arrived in Mozambique on Tuesday. They were taken from the global cholera vaccine stockpile, which is fully-funded by Gavi. Gavi is also supporting operational costs of the campaign. The use of the stockpile for outbreak response is managed by the International Coordinating Group (ICG), which features representatives from WHO, UNICEF, IFRC and MSF.
Since the stockpile was launched in 2013, millions of doses every year have helped tackle outbreaks across the globe. In the fifteen years between 1997 and 2012, just 1.5 million doses of oral cholera vaccine were used worldwide. In 2018 alone, the stockpile provided 17 million of doses to 22 different countries. Since the beginning of 2019, more than 6 million doses have already been shipped to respond to outbreaks or address endemic cholera in many countries including Democratic Republic of the Congo, Nigeria, Somalia and Zimbabwe.”
Worldwide, cholera infects between 1.3 and 4 million people, killing between 21,000 and 143,000. (The numbers are difficult to pinpoint because of other infectious diseases and situations, like war and famine, that kill alongside cholera in places where it hits.) There are three vaccines used by WHO in response to cholera epidemics, and all are stockpiled and ready to go in different parts of the world should the need arise.
In 2010, United Nations peacekeepers sent to Haiti after a massive earthquake introduced cholera to the country, with a sizeable epidemic lasting for months before it was brought under control. More recently, in Yemen, the civil war there has destroyed public health and public services infrastructures, leading to the contamination of water and the unavailability of sanitation. As a result, a cholera epidemic there continues to this day, making it the worst cholera epidemic in recorded history with more than 1 million people sick and thousands dead.
The cholera vaccine dates back to the 1880s, when, building on the work of Louis Pasteur, scientists developed an injected vaccine and a superior oral vaccine. The oral vaccine would take over as the preferred vaccine since the injected vaccine didn’t provide lasting immunity. However, making the oral vaccine at a large scale proved to be a challenge. More recent vaccines have been more effective when given strategically to at-risk groups, followed by a booster dose and combined with epidemiological and biological controls (i.e. potable water and sanitation) have shown effectiveness at preventing and stopping epidemics.