Oct. 19 (UPI) — Amid what it calls an “unprecedented rise in cholera cases worldwide,” the World Health Organization said Wednesday that a “dire shortage” of cholera vaccines is requiring temporary suspension of its two-dose strategy.
WHO called it an “exceptional decision” that reflects the “grave state” of the cholera vaccine stockpile. The change in strategy will allow vaccine doses to be used in more countries over the short term, the international health group said in a news release.
Over the longer term, WHO said urgent action is needed to increase global vaccine production.
“A strained global supply of cholera vaccines has obliged the International Coordinating Group — the body which manages emergency supplies of vaccines — to temporarily suspend the standard two-dose vaccination regimen in cholera outbreak response campaigns, using instead a single-dose approach,” WHO said.
Cholera is a severe diarrheal illness that can spread and kill quickly. WHO said 29 countries have reported cholera cases since January, including large outbreaks in Haiti, Malawi and Syria.
By comparison, fewer than 20 countries on average reported outbreaks over the previous five years, WHO said, explaining the global trend toward more numerous, widespread and severe outbreaks is spurred by “floods, droughts, conflict, population movements and other factors that limit access to clean water and raise the risk of cholera outbreaks.”
WHO’s announcement comes on the heels of some of the nation’s top infectious disease doctors expressing grave concerns to UPI about shortages of U.S. cholera vaccine.
One such expert, Dr. Peter Hotez, co-director of Texas Children’s Hospital Center for Vaccine Development, told UPI in an email Wednesday that the situation is worrisome.
“Clearly, our global cholera vaccine stockpile is falling through the cracks,” said Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.
Hotez added: “Beyond COVID vaccines this cholera vaccine emergency is [the] second reason why we need to find ways to broaden the global vaccine ecosystem in ways that go beyond the multinational companies.
“The multinationals do a lot of good, but they are not tasked to address epidemic or pandemic threats.”
Hotez noted that a dozen years ago, he, along with infectious disease experts Drs. Matthew Waldor and John D. Clemens co-authored a New England Journal of Medicine article that urged creation of a national cholera vaccine stockpile as a “humanitarian and diplomatic resource.”
Hotez said the trio had proposed a U.S. cholera vaccine stockpile “both for humanitarian reasons and because it’s an essential component of global health security. Our rationale remains valid.”
That never materialized. No federal vaccine supply exists in the Strategic National Stockpile to serve as backup in case of a disaster-related mass cholera outbreak in this country.
Right now, the only Food and Drug Administration-approved cholera vaccine, Vaxchora, targeting U.S.-based international travelers heading to cholera hotspots, sits on the U.S. drug shortages list and has been unavailable for nearly two years.
Meanwhile, WHO’s global oral cholera vaccine stockpile began in 2013 and has shipped more than 123 million doses to 23 countries — from Bangladesh to Zimbabwe, WHO recently told UPI.
Now, WHO describes the current supply of cholera vaccines as “extremely limited.”
Of the total 36 million doses forecast to be produced in 2022, WHO said 24 million doses have already been shipped and an additional 8 million doses have been approved for the second-round for emergency vaccination in four countries.
According to the international health group, vaccine manufactures are producing at their maximum current capacity, so there is no short-term solution to increase production. WHO said temporary suspension of the two-dose strategy will let remaining cholera vaccine doses be “redirected for any needs for the rest of the year.”
Shanchol and Euvichol-Plus are the two-dose cholera vaccines currently available for mass vaccination campaigns through WHO’s global stockpile.
The international health group acknowledged the shortcomings of cutting back to a single dose of cholera vaccine.
“The one-dose strategy has proven to be effective to respond to outbreaks, even though evidence on the exact duration of protection is limited, and protection appears to be much lower in children,” WHO said in the release.
“With a two-dose regimen, when the second dose is administrated within six months of the first, immunity against infection lasts for three years.”
But the group said the benefit of supplying one dose still outweighs no doses.
Although the temporary interruption of the two-dose strategy will lead to a reduction and shortening of immunity, WHO said, more people will be able to get vaccinated and have “protection in the near term, should the global cholera situation continue deteriorating.”
