As a wave of cholera outbreaks spreads around the world, Gavi, the Vaccine Alliance said it expects the global shortage of oral cholera vaccines to continue until the end of 2025.

Supply of oral cholera vaccines for preventative use could catch up to demand by 2026, but “urgent action is needed,” according to a vaccine production roadmap published by Gavi, the World Health Organization (WHO) and other global health partners on Monday.

There are currently still enough vaccine supplies to respond to emergencies, Gavi said.

“The good news is we have doses to meet all emergency demand despite the rise in outbreaks, and that is expected to continue,” said Dr Derrick Sim, head of vaccine markets and health security at Gavi, adding that the global resurgence of cholera “underscores the need to prevent outbreaks before they occur.”

The past ten years have seen a steady increase in the availability of oral cholera vaccines. Global production rose from 4 million doses in 2012 to 35 million by 2022, with a similar number of vaccines expected to be produced this year.

“Every vaccine dose delivered to a person in need today is the result of years of planning,” Sim said. “The ultimate solution to both sustainable oral cholera vaccine supply and cholera control lies in our collective ability to step-up up our efforts on prevention programmes.”

But the recent spike in cholera outbreaks driven by climate shocks, war and humanitarian crises have caused a surge in demand for the vaccines for emergency response, limiting the availability of supplies for preventative use.

Between 2021 and 2022, 48 million oral cholera vaccines were needed for emergency response, 10 million more than in the entire previous decade.

“The outlook is bleak,” WHO incident manager for the global cholera response Henry Gray said at a press briefing on Friday. “We’re not able to provide enough vaccines.” Only 8 million of 18 million doses requested by WHO have been made available so far in 2023, Gray added.

The WHO has warned that climate change is a major threat to global health, and that cholera is one of the diseases that is most likely to be affected. Extreme weather events, such as floods and droughts, increase the risk of cholera outbreaks by contaminating water supplies with sewage, waste and bacteria. People displaced by climate shocks are also less likely to have access to clean water and sanitation, increasing their risk of infection.

The ongoing cholera outbreak in Malawi, which began at the end of the cyclone season in March last year, is the deadliest in the country’s history, according to the WHO.

In response to a shortage of oral cholera vaccines last year, WHO advised countries to ration supplies during outbreaks by giving just one of the two-dose vaccine to patients. The WHO still ran out of vaccines by the end of the year.

Image Credits: World Health Organization (WHO).