A woman takes oral cholera vaccine in a camp for internally displaced people in South Sudan. Photo courtesy of Ali Ngethi, WHO.
When violence erupted in South Sudan at the end of 2013, tens of thousands of people fleeing the conflict sought refuge in United Nations bases positioned around the country in the hope that peacekeepers stationed there would protect them. The bases were quickly overwhelmed, with families crammed together with little or no access to safe water or sanitation. Then the rainy season approached, increasing the risk of waterborne diseases, in particular cholera, which is endemic to the country – with the potential for explosive outbreaks in the congested camps.
Yet when a cholera outbreak was declared in South Sudan five months later, the displaced people living in the makeshift camps at UN sites were largely unaffected, with little or no transmission of cholera. A timely decision to initiate prevention and control measures, including pre-emptively vaccinating displaced people in UN sites with oral cholera vaccine (OCV), almost certainly averted increased illness and death amongst the vulnerable camp inhabitants who had been at high-risk of the disease.
Cholera has been responsible for seven pandemics in the last two centuries and an estimated 1.4 billion people are at still risk of the disease in endemic countries. More than 100,000 people die of cholera each year, half of them children, although only a fraction of cases and deaths are reported.
Cholera is a preventable and treatable disease, but slow progress in providing access to safe water and sanitation for all populations, lack of access to healthcare for those who are sick, and the emergence of new and more virulent strains of cholera mean the disease still inflicts a heavy burden of disease on society. Humanitarian crises, whether due to conflict or natural disasters, often create conditions in which cholera thrives.
The actions taken to prevent a full-scale outbreak of cholera in South Sudan’s UN-controlled camps were a direct result of a renewed international commitment to combatting the disease as well as the availability of a safe and effective vaccine. Since 2013 the World Health Organization (WHO), together with three key partners (IFRC, MSF, UNICEF), has managed a global stockpile of OCV, which can be used for outbreak response and humanitarian crises.
“Living conditions in the camps in South Sudan were horrible. By early 2014 acute watery diarrhoea and other water borne diseases were on the rise. We knew that unless we rapidly put in place preventive measures we would have hundreds, if not thousands of cases of cholera,” says Dr. Abdinasir Abubakar, medical officer for the WHO in South Sudan. “The Ministry of Health requested vaccines from the global stockpile and within a few weeks 250 000 doses were being shipped in and the vaccination campaigns were carried out by Medair and Médecins Sans Frontières.”
The global stockpile of OCV initially made available 2 million doses of the vaccine, funded by five donors: the Bill and Melinda Gates Foundation, the ELMA Vaccines and Immunization Foundation, the EU Humanitarian Aid and Civil Protection department (ECHO), the Margaret A Cargill Foundation and the USAID Office of Foreign Disaster Assistance. In 2015, with funding from the GAVI Alliance, the number of doses available for use in both endemic hotspots and emergency situations is expected to rise to around 3 million.
It was the rapid spread of cholera following the 2010 earthquake in Haiti that reminded the world the disease was still a major killer. An estimated 9000 people have already died of cholera in Haiti since the epidemic began and an estimated 700,000 are infected. But in fact, cholera has always placed a heavy disease burden on countries, particularly in the Regions of Africa and South-East Asia. Recent years have seen epidemics emerge in the Horn of Africa, Sierra Leone, Yemen and Zimbabwe, among others.
In 2011 the WHO World Health Assembly (WHA) recognized cholera as a global public health priority and called for the revitalization of the Global Task Force on Cholera Control (GTFCC), which was originally established in 1991 in response to the re-emergence of the disease in Latin America and Africa. The WHO-led network aims to end cholera deaths through strengthening international collaboration and increasing coordination among partners.
“Selective use of OCV for so-called endemic ‘hot spots’ and in humanitarian emergencies is a powerful tool to have in our armoury, but to combat this disease we need a global integrated and innovative approach that includes better prevention through improved access to clean water and sanitation as well as better surveillance, preparedness and response to outbreaks,” says Dr. William Perea, coordinator for the control of epidemic diseases for the WHO.
“There is a renewed global commitment to the vision of dramatically reducing death and disease from cholera. Through collective action we can focus, catalyse and help coordinate support for countries to help them put in place evidence-based measures to control this disease,” he says.