The head of the World Health Organization warned Wednesday that blanket booster programs in rich countries risk prolonging the world's battle with COVID-19 and said that “no country can boost its way out of the pandemic.”

WHO Director-General Tedros Adhanom Ghebreyesus said the priority must be to reduce deaths and help all countries meet minimum vaccination targets that many still haven't reached. And he noted that “the vast majority of hospitalizations and deaths are in unvaccinated people, not unboosted people.”

Tedros said that, while vaccines have saved many lives this year, their unequal sharing “has cost many lives.” In 2021, 3.5 million people were lost to COVID-19, he said, and “all of us need to take extra precautions” as the new omicron variant advances.

The WHO chief has previously called for a moratorium on boosters for healthy adults until the end of this year to counter unequal global vaccine distribution. He said at an online news conference Wednesday that about 20% of vaccine doses being given every day are currently boosters or additional doses.

“Blanket booster programs are likely to prolong the pandemic rather than ending it, by diverting supply to countries that already have high levels of vaccination coverage, giving the virus more opportunity to spread and mutate," Tedros added.

He said it's “frankly difficult to understand” that three-quarters of health workers in Africa remain unvaccinated, and distortions in global supply mean that only half of WHO's member countries have been able to meet a target of vaccinating 40% of their populations by the end of this year.

Tedros renewed a call for manufacturers and other countries to prioritize the COVAX program to get doses to needier nations and “work together to support those who are furthest behind."

“Unless we vaccinate the whole world ... I don't think we can end this pandemic,” Tedros said. But he added that authorities now know the virus better and have effective tools to fight it; “we need to add to that comprehensive implementation and equity, and hope 2022 will end this pandemic.”

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