In South Korea, there's a long hallway lined with walk-in refrigerators. Inside are boxes filled with oral cholera vaccines. This is the emergency cholera vaccine stockpile — and boxes are flying off the shelves to places like Angola, Sudan and South Sudan.
"At the moment, we're shipping about 5 million doses every month, so this means that as soon as the box comes in, another one is going out," says Allyson Russell, an epidemiologist at Gavi, the Vaccine Alliance, and a senior program manager for outbreaks and global health security. Gavi, a global public-private organization, funds the stockpile and aims to have a little more than 5 million doses available at any given time, although it has had trouble in the past meeting this target.
There are similar stockpiles around the world. In freezers in Switzerland, there are Ebola vaccines. Elsewhere there are meningitis vaccines stored up; same with yellow fever vaccines. While some are kept at ultra-cold temperatures, like the Ebola vaccines, most only need to be refrigerated.
"Imagine sticking your hand in a refrigerator to get out your groceries," says Russell.
The first global stockpile was established in 1997 when major meningitis outbreaks in Africa prompted public health crisis. The vaccines are available to any country in the world. These stockpiles are now in the spotlight because, for the first time, researchers have quantified just how many lives have been saved by drawing on the stored vaccines. But this news comes against the backdrop of uncertainty. There are new concerns about what the future of these global stockpiles will look like amid a major drop in global health funding.
Exactly how much of a 'game changer'?
Russell spends her days immersed in the details of the stockpile system. She knows which countries have emailed in the form to request doses from the stockpile. She knows whether the doses are being raced to an outbreak via chartered flight or in the cargo of a commercial airplane.
And one thing is clear to her. "You can see how vaccines change the trajectory of what happens [in an outbreak]," she says. "Vaccine can really be a game changer."
But, she says, she's never known exactly how much of a "game changer" these stockpiles are — until now.
Researchers have crunched the numbers. They looked at more than 200 outbreaks over the past 20-some years, modeling what would happen without the vaccines. Nick Scott, a co-author of the study published this month in the British Medical Journal — Global Health, says the results were exciting: A 60% reduction in cases and deaths from outbreaks because of the stockpile.
"That's quite an amazing thing," said Scott, who is head of modeling and biostatistics at the Burnet Institute in Melbourne, an independent medical research group. That 60% drop means about 6 million cases were averted and 300,000 deaths were averted.
"This study really was meant to ask the question of, are GAVI stockpiles worthwhile? Is it worthwhile to have them?" says Dr. Ruth Karron, who is director of the Johns Hopkins Vaccine Initiative and was not involved in the study. "And I think that the answer — very robustly — is absolutely."
The research — which was funded by Gavi and started in early 2024 with the goal of helping inform its strategic planning — found over $32 billion dollars in economic benefits from the stockpiles, given there were fewer deaths and less disability in the 200-some outbreaks researchers considered.
The researchers say this is a significant underestimate and the true economic benefits are likely much higher. That's because this calculation does not take into account things like the cost of outbreak response that are avoided or the economic disruptions created by large outbreaks. Based on Gavi's financial planning documents, procurement for the stockpiles costs less than $100 million a year.
Scott's team also found that speed really matters.
"When there is an outbreak, the faster the vaccine response can start, the more impactful it will be," he says. This matters because containing a disease's spread can mean avoiding huge social disruptions.
"What we found is that these vaccines are really critical for preventing things like school closures, business closures, travel restrictions," Scott said.
The importance of speed is one of the reasons the stockpiles exist in the first place.
"It can easily take up to a year to make these vaccines. Ebola vaccines take a year. Meningitis vaccines take about four to six months," Russell says. "If you were to place the order and then make the vaccines, who knows what would happen to the outbreak."
However, Scott says, having the vaccines ready is not enough. There also need to be mechanisms in place to get the doses to the outbreak and then administer them to people who live and work in the affected area. As international aid organizations face historic funding cuts these steps could get harder.
'Everything is up for question'
Karron says the findings come at a particularly important time.
Global health funding is dropping to a 15-year low, according to a study published this month in the medical journal The Lancet. And it's forcing international health organizations to grapple with what they can afford to keep and what they have to let go. These days everything is on the table, including the global stockpiles of emergency vaccines, says Karron.
Gavi is almost $3 billion short of its budget goal for the next five years. Part of the shortfall comes from the U.S. announcing last month that it will cut off support for Gavi until it is able to "re-earn the public trust." Health and Human Services Secretary Robert F. Kennedy Jr. explained the decision by saying Gavi had neglected issues of vaccine safety, an accusation Gavi vigorously denies. Critics says the study RFK Jr. cited as evidence is flawed.
This week, the organization's board is meeting to figure out what to prioritize.
"So obviously, everything is up for question," Karron says.
One challenge with the stockpiles is that stored doses can expire, explains Karron. Doses made for routine immunizations are, generally, used quickly and don't bump up against their expiration dates. That's not a guarantee with the stockpile. Gavi does have a system where once vaccines in the stockpile reach one year left in their shelf life, they can be used in a preventive program — for example in a high-risk location where researchers anticipate meningitis outbreaks. However, Karron says, that is not always possible.
"So, the question is: Is it worth the investment knowing that you might have some vaccine that goes to waste?" she asks. She says the clear answer from this study is that it's in everyone's interest to keep the emergency vaccine stockpiles fully stocked.
"If we don't want some of these diseases, like Ebola, to come to our [U.S.] shores, we really need to contain them at the source," Karron says.
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