Cholera

Update

Global cholera vaccine stockpile runs empty as 16 countries report outbreaks

February 26, 2024—Doctors Without Borders/Médecins Sans Frontières (MSF) is extremely concerned about a recent announcement that the global cholera vaccine stockpile has been exhausted, at a time when there is very little capacity to manufacture more vaccines. As a high number of countries are reporting outbreaks, more manufacturers—existing and new—must urgently help boost the global supply.

Putting cholera in context

Cholera is a highly contagious disease that occurs in settings without clean water and proper sanitation—from poor, remote villages to overcrowded cities, refugee camps, and conflict zones. It causes profuse diarrhea and vomiting, and without treatment can quickly lead to death by intense dehydration. In recent years we responded to dozens of outbreaks, including massive epidemics in post-earthquake Haiti and war-torn Yemen.

70,600

patients treated by MSF

for cholera in 2023

8,500

cholera patients admitted

in 2022 to MSF facilities in Haiti

14,224

people immunized in 2022

by MSF staff in Lebanon

Facts about cholera

Cholera is a bacterial infection that causes cells lining the intestine to produce large amounts of fluid. It spreads when someone ingests food or water contaminated with vomit or feces from a person carrying the disease. Contaminated food or water supplies can rapidly cause massive outbreaks.

Cholera symptoms typically appear within 2-3 days of infection and vary widely, from mild to severe. In severe cases, people have profuse watery diarrhea, vomiting, and leg cramps, leading to dehydration and shock that can become fatal within hours if patients don't receive care.

Drinking and using safe water, using clean latrines or toilets, washing hands with soap, and ensuring good food hygiene are all ways to avoid the disease–but are often difficult or impossible for individuals in settings where cholera occurs. Prevention and control require measures at the community level, especially in making communally-supplied water safe for drinking.

Oral vaccines are another powerful tool being used more and more to help prevent cholera and to contain outbreaks. But vaccination alone cannot end cholera–improvements in sanitation and hygiene systems are also essential. Protection with current vaccines may not last beyond 3-5 years, and despite recent increases in vaccine production, the global supply still falls short of meeting today’s needs.

Definitive cholera diagnosis requires a laboratory test. For field settings without access to lab facilities there are rapid tests available, but they are less reliable. Declaration of an outbreak therefore requires laboratory confirmation. Diagnosis of individual patients during outbreaks is typically made without these tests, based on a patient history and symptoms and on clinical examination.

Most cases of cholera are simple to treat, and treatment is highly effective if patients receive it promptly. Mild and moderate cases of cholera are treated by having patients drink large amounts of oral rehydration solution—a mixture of sugars and salts in water. The sickest patients may need intravenous fluids and antibiotics. Without treatment, patients may die within hours, but with proper care the death rate usually drops to 2% or less.

How MSF responds to cholera

At MSF we started responding to cholera epidemics in the 1980s, and are gradually working to improve the effectiveness of our response. More recently one of our larger responses was in Haiti, where a cholera epidemic that began shortly after the devastating 2010 earthquake has so far caused over 800,000 cases and nearly 10,000 deaths. Thankfully there have been no new cases since February 2019, thanks to years of intensive efforts by Haitian health authorities and international organizations. Among our current projects, we are active in Yemen, which continues to face the world's largest cholera epidemic since modern record-keeping began in 1949. Amid ongoing full-scale war that caused the country's infrastructure and health care system to collapse, over 2 million people in Yemen have suffered from cholera since the outbreak's start in 2016.

An effective response to cholera involves engaging on several different fronts at the same time—and as fast as possible—to treat sick patients and to stop transmission within communities. The key pillars of this strategy rely on MSF's medical staff working alongside epidemiologists, water and sanitation experts, logistics managers and community health promoters. If patients receive the care they need, deaths can be reduced from as high as 50% to below 2%. Since an effective oral vaccine became available within the past decade, we have also incorporated large-scale vaccination campaigns into our response.

Cholera kits

A big part of MSF’s ability to respond quickly is our standardized, pre-positioned cholera treatment kits that come equipped with rehydration salts, antibiotics, and IVs, along with buckets, boots, chlorine, and plastic sheeting—in short, everything needed to hit the ground running after an outbreak is confirmed.

Outbreak investigation

Once cholera is confirmed, MSF conducts an outbreak investigation, or supports others to do so. This involves mapping where patients are coming from so that responders can prioritize the most affected areas. Throughout the epidemic epidemiologists continue looking into new cases in other areas.

Treatment facilities for patient care

When an outbreak is reported, MSF sets up dedicated cholera treatment centers at central locations. These centers are specialized isolation wards for rapidly treating large numbers of patients while preventing disease spread beyond the facility—patients, caregivers, and medical staff have controlled entrances, exits, and decontamination areas, where they are sprayed with chlorine. In some situations, patients with mild cases are treated at simpler facilities called oral rehydration points, set up within or close to affected communities. This is especially important in settings where sick patients otherwise face a long journey to reach treatment, since cholera can cause death very quickly.

Water and sanitation improvements

MSF water and sanitation staff work to ensure availability of sufficient latrines and adequate supplies of clean water from safe sources, at both the home and communal levels. This typically involves activities ranging from distributing soap, clean buckets, and water disinfection tablets for home use, to providing bucket chlorination at water sources before water is carried home. In response to the Rohingya refugee crisis in Bangladesh, MSF set up water distribution systems in Cox's Bazar, drilled boreholes and tube wells, rehabilitated and constructed latrines, and distributed domestic water filters.

Community health promotion

During outbreaks, health promoters visit schools, churches, markets, and homes to help people implement measures to protect themselves against cholera and know what to do if they develop diarrhea. For example, in 2016 during the cholera outbreak in Democratic Republic of Congo, health promoters visited villages to encourage people to wash their hands, to safely dispose of waste, and to get help as soon as symptoms of cholera begin.

Vaccination

MSF is increasingly using vaccination to help curb cholera outbreaks that are predicted to start soon or have just begun. A big advantage of the cholera vaccine is that it is oral, so it’s very simple to administer—people simply drink it. But globally there is a shortage of vaccines available, so vaccination can't be used nearly as widely as it should be. MSF conducts vaccination campaigns both in response to cholera outbreaks and to prevent future ones. In one recent example, MSF vaccinated nearly 200,000 people as a prevention strategy in Juba, South Sudan, where cholera is endemic.

Advocacy

Our advocacy work focuses on the urgent need to expand global supplies of vaccine and to develop and confirm the effectiveness of simpler strategies for conducting mass vaccination campaigns. We participated in establishing the Global OCV Stockpile, maintained by the World Health Organization and supported by Gavi, the Vaccine Alliance, that helps provide cholera vaccine for emergency use in outbreaks. As vaccine supplies gradually increase, we will continue advocating for more widespread use, including in routine vaccination rather than just to stop outbreaks once they’ve begun.

Research

Finding ways to optimize strategies for using cholera vaccines is an important part of our response. For example, in 2016 we showed that although the vaccine is usually given in two doses that confer 3-5 year protection, one dose still curbs transmission effectively in the short term. MSF used this one-dose strategy in Lusaka, the densely populated capital of Zambia, to vaccinate over half a million people in just two weeks. We are also assessing simpler two-dose vaccination campaign strategies for use when enough vaccine is available, based on recent findings that the cholera vaccine remains effective for at least four weeks without refrigeration. We have also researched more efficient ways to conduct mass vaccination campaigns like using mapping and surveillance techniques to help determine priority areas for immunization.