Home News & Events Cholera vaccine shortage coincides with major outbreak; The latest health stories from...

Cholera vaccine shortage coincides with major outbreak; The latest health stories from around the world

The world has run out of cholera vaccines—just when the deadly disease is on a rampage not seen in many years. Fifteen countries are currently reporting active outbreaks, with more than 40,900 cases and 775 deaths reported in January alone. But all available doses of oral cholera vaccines in the global stockpile have been allocated until mid-March, Philippe Barboza, cholera team lead at the World Health Organization (WHO), said on 23 February. He said there is now “no buffer for unforeseen outbreaks or preventive campaigns.” https://www.science.org/content/article/world-s-stockpile-cholera-vaccine-empty-relief-way

The catastrophic shortage is a result not just of a surge in cases, but also of an overdependence on a single vaccine manufacturer, EuBiologics in Seoul, South Korea. But hope is on the horizon. EuBiologics is working to ramp up production of a simplified vaccine, and companies in South Africa and India are preparing to enter the market as well. The shortage “will lessen in 2024 and should be substantially addressed by 2025,” says Julia Lynch, director of the cholera program at the International Vaccine Institute (IVI), also in Seoul.  

Many public health experts attribute the current surge in cholera, which began in late 2022, at least partially to climate change. Extreme weather events in Pakistan, Malawi, and Mozambique have destroyed health and sanitation infrastructure, allowing the bacterium to thrive. Armed conflict and displacement of people in the Democratic Republic of the Congo and Yemen have also led to outbreaks. 

The two-dose oral cholera vaccine, developed by IVI based on earlier research in Vietnam, contains several strains of inactivated V. cholerae bacteria. Two doses given 2 weeks apart can offer robust protection for at least 3 years, and, when deployed early enough, can prevent outbreaks from ballooning. 

The global stockpile of the vaccine, established in 2012, is managed by an International Coordinating Group on Vaccine Provision made up of experts from WHO, UNICEF, MSF, and the International Federation of Red Cross and Red Crescent Societies. It can rapidly send vaccine to countries in need. The number of doses available for shipment reached 36 million in 2023 and could be close to 50 million this year. 

But all will be needed to fight ongoing outbreaks, and the shortage has forced some difficult choices. In late 2022, the coordinating group announced it would stop giving people second doses; even a single dose, studies have found, can provide substantial protection against cholera for a few years at least.  

To boost supply, EuBiologics has simplified its original vaccine. The new formulation, Euvichol-S, contains two strains of the inactivated V. cholerae bacteria instead of five, and the recipe drops a heat inactivation step. That makes the vaccine easier to produce and about 20% cheaper. This will further expand EuBiologics production capacity by 38%, to about 52 million doses annually, according to a December 2023 press release from IVI. A phase 3 trial in Nepal in 2022 showed the simplified version protects as well as the original. 

Euvichol-S is currently under review for “prequalification,” a seal of approval from WHO that the company expects to come through in April, says EuBiologics Director Rachel Park. Then Gavi, the Vaccine Alliance will procure the vaccine at roughly $1.5 per dose to replenish the stockpile. EuBiologics is also building a new facility that could expand its production capacity to 90 million doses annually. 

To end the reliance on a single manufacturer, IVI in 2022 began to help Biovac, a South African company, set up a facility to produce the simplified vaccine. Biovac tells Science it plans to start clinical trials in 2025 and hopes to produce 30 million vaccine doses annually in 5 or 6 years. Biovac has been encouraged by a so-called advanced market commitment from Gavi, a pledge to buy many vaccine doses at established prices. So is the Indian manufacturer Biological E, which plans to produce IVI’s simplified vaccine. 

Another Indian biotechnology company, Bharat Biotech, is working on its own low-cost cholera vaccine, Hillchol. Bharat has said little about its progress and did not respond to questions, but a phase 3 trial—at various locations in India—finished in early 2023, Lynch says.