The U.N.-backed vaccine program is so far behind schedule that not even 10 percent of the population in poor countries is fully vaccinated, experts say.WASHINGTON — Already grappling with divisions in his own country over vaccine mandates and questions about the ethics and efficacy of booster shots, President Biden is facing another front of discord: a split among world leaders over how to eradicate the coronavirus globally, as the highly infectious Delta variant leaves a trail of death in its wake.At a virtual summit on Wednesday, while the annual United Nations General Assembly meeting is underway, Mr. Biden will try to persuade other vaccine-producing countries to balance their domestic needs with a renewed focus on manufacturing and distributing doses to poor nations in desperate need of them.Covax, the United Nations-backed vaccine program, is so far behind schedule that not even 10 percent of the population in poor nations — and less than 4 percent of Africa’s population — is fully vaccinated, experts said. Millions of health care workers around the world have not had their shots.The push, which White House officials say seeks to inject urgency into vaccine diplomacy, will test Mr. Biden’s doctrine of furthering American interests by building global coalitions. Coming on the heels of the United States’ calamitous withdrawal from Afghanistan last month that drew condemnation from allies and adversaries alike, the effort to rally world leaders will be closely watched by public health experts and advocates who say Mr. Biden is not living up to his pledges to make the United States the “arsenal of vaccines” for the world.“This is one of the most moral questions of our time,” Representative Rosa DeLauro, Democrat of Connecticut, said last week. “We cannot let the moment pass. And the United States can recapture its leadership role by taking on what is one of the greatest humanitarian causes ever — and we need to bring this pandemic to an end.”The landscape is even more challenging now than when Covax was created in April 2020. Some nations in Asia have imposed tariffs and other trade restrictions on Covid-19 vaccines, slowing their delivery. India, home to the world’s largest vaccine maker, has banned coronavirus vaccine exports since April.At the same time, the Biden administration is preparing to offer booster shots to millions of already vaccinated Americans, despite criticism from World Health Organization officials and other experts who say the doses should go to low- and lower-middle-income countries first. On Friday, a Food and Drug Administration panel recommended Pfizer booster shots for those over 65 or at high risk of severe Covid-19, a broad and ill-defined category. The agency is expected to authorize the shots this week.Biden administration officials said they are determined to eliminate the disease both at home, including with booster shots, and abroad. “We do understand that this has not been spread around equally,” Erica Barks-Ruggles, the State Department’s senior adviser on international organizations, told reporters on Monday, previewing the U.N. meeting.Hours later, on a conference call with reporters Monday, the W.H.O.’s chief scientist, Dr. Soumya Swaminathan, disagreed.“It’s a myth when people say we can do both — unfortunately, that’s not true,” Dr. Swaminathan said, referring to Mr. Biden’s booster strategy. “At the moment, we are in a zero sum game.”She and other experts are calling for a coordinated global vaccination strategy in which doses would be distributed equitably around the globe, rather than each country tending to its own needs.Officials said Wednesday’s summit would be the largest gathering of heads of state to address the coronavirus crisis. It aims to encourage pharmaceutical makers, philanthropists and nongovernmental organizations to work together toward vaccinating 70 percent of the world’s population by the time the U.N. General Assembly meets in September 2022, according to a draft document the White House sent to the summit participants.“We also know this virus transcends borders,” Mr. Biden said on Sept. 9. “That’s why, even as we execute this plan at home, we need to continue fighting the virus overseas, continue to be the arsenal of vaccines.”“That’s American leadership on a global stage,” he said.Experts estimate that 11 billion doses are necessary to achieve widespread global immunity. The United States has pledged to donate more than 600 million — more than any other nation — and the Biden administration has taken steps to expand vaccine manufacturing in the United States, India and South Africa. In addition, the White House is in talks to buy another 500 million doses from Pfizer to donate overseas, but the deal is not final.The 27-nation European Union aims to export 700 million doses by the end of the year.The distribution of Covax vaccines is so far behind schedule that not even 10 percent of the population in poor nations is fully vaccinated.Brian Inganga/Associated PressBut as recently as July, only 37 percent of people in South America and 26 percent in Asia had received at least one vaccine shot, according to Rajiv J. Shah, the head of the U.S. Agency for International Development during the Obama administration. The figure stood at just 3 percent in Africa, Mr. Shah wrote in an essay published last month in Foreign Affairs.An estimate by the ONE Campaign, which fights extreme poverty and preventable disease, showed that the leading seven developed nations would together be sitting on a surplus of more than 600 million vaccine doses by the end of 2021. That is enough to give every adult in Africa one shot.Most doses that have been committed, however, will not be delivered to the needier nations, nor injected into arms, until next year. Given the sluggish distribution, said Dr. Kate O’Brien, the World Health Organization’s top vaccines expert, “we can see clearly from the data that’s coming out that we are very far” from vaccinating 70 percent of the world’s population by the middle of next year, as initially projected.The president is also under intense pressure from global health advocates who say donating doses is not enough and want him to scale up manufacturing capacity overseas.On Monday, activists staged a demonstration near the U.N. headquarters in New York calling on Mr. Biden to “end vaccine apartheid.” A coalition of nearly 60 human rights and other advocacy groups sent Mr. Biden a letter urging him to back a $25 billion investment that would produce eight billion doses within a year — and to ask Congress to include a specific line item for it in the $3.5 trillion “Build Back Better” budget legislation that lawmakers are now considering.“We cannot ‘donate’ our way to safety,” they wrote.That growing gap between the vaccine haves and the vaccine have-nots has led to a rift between wealthy countries and most of the rest of the world, one that has only deepened with the rampant spread of the Delta variant and potentially thousands of others that are on the rise. Several of the most virulent variants were first identified in lower-income countries, including South Africa and India — both of which have fully vaccinated only 13 percent of their populations.More than 100 low-income countries are banking on Mr. Biden to lean on the European Union and Group of 7 states at the summit on Wednesday to agree to waive intellectual property rights to vaccine production so that they can be shared with manufacturers in other, developing nations. Some of the leading coronavirus vaccines are produced in Europe — including Pfizer-BioNTech in Germany and AstraZeneca in England — and officials there have been accused of putting potential profits ahead of beating back the pandemic.The European Union again objected to a plan to waive the vaccine property rights at a closed-door World Trade Organization meeting last week in Geneva, according to a senior European diplomat familiar with the discussion.The Biden administration has supported a waiver, although not as forcefully as its advocates want.“The action by the U.S. is particularly important to shift things forward, and make people come around the table and discuss these issues,” said Zane Dangor, a special adviser to South Africa’s foreign minister. He said European Union officials “would like to kick this discussion further down the road.”“The more we delay in ensuring equitable access, the longer we wait, the longer the pandemic becomes,” Mr. Dangor said last week..css-1xzcza9{list-style-type:disc;padding-inline-start:1em;}.css-3btd0c{font-family:nyt-franklin,helvetica,arial,sans-serif;font-size:1rem;line-height:1.375rem;color:#333;margin-bottom:0.78125rem;}@media (min-width:740px){.css-3btd0c{font-size:1.0625rem;line-height:1.5rem;margin-bottom:0.9375rem;}}.css-3btd0c strong{font-weight:600;}.css-3btd0c em{font-style:italic;}.css-w739ur{margin:0 auto 5px;font-family:nyt-franklin,helvetica,arial,sans-serif;font-weight:700;font-size:1.125rem;line-height:1.3125rem;color:#121212;}#NYT_BELOW_MAIN_CONTENT_REGION .css-w739ur{font-family:nyt-cheltenham,georgia,’times new roman’,times,serif;font-weight:700;font-size:1.375rem;line-height:1.625rem;}@media (min-width:740px){#NYT_BELOW_MAIN_CONTENT_REGION .css-w739ur{font-size:1.6875rem;line-height:1.875rem;}}@media (min-width:740px){.css-w739ur{font-size:1.25rem;line-height:1.4375rem;}}.css-9s9ecg{margin-bottom:15px;}.css-16ed7iq{width:100%;display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;-webkit-box-pack:center;-webkit-justify-content:center;-ms-flex-pack:center;justify-content:center;padding:10px 0;background-color:white;}.css-pmm6ed{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;}.css-pmm6ed > :not(:first-child){margin-left:5px;}.css-5gimkt{font-family:nyt-franklin,helvetica,arial,sans-serif;font-size:0.8125rem;font-weight:700;-webkit-letter-spacing:0.03em;-moz-letter-spacing:0.03em;-ms-letter-spacing:0.03em;letter-spacing:0.03em;text-transform:uppercase;color:#333;}.css-5gimkt:after{content:’Collapse’;}.css-rdoyk0{-webkit-transition:all 0.5s ease;transition:all 0.5s ease;-webkit-transform:rotate(180deg);-ms-transform:rotate(180deg);transform:rotate(180deg);}.css-eb027h{max-height:5000px;-webkit-transition:max-height 0.5s ease;transition:max-height 0.5s ease;}.css-6mllg9{-webkit-transition:all 0.5s ease;transition:all 0.5s ease;position:relative;opacity:0;}.css-6mllg9:before{content:”;background-image:linear-gradient(180deg,transparent,#ffffff);background-image:-webkit-linear-gradient(270deg,rgba(255,255,255,0),#ffffff);height:80px;width:100%;position:absolute;bottom:0px;pointer-events:none;}.css-uf1ume{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-box-pack:justify;-webkit-justify-content:space-between;-ms-flex-pack:justify;justify-content:space-between;}.css-wxi1cx{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction:column;-webkit-align-self:flex-end;-ms-flex-item-align:end;align-self:flex-end;}.css-12vbvwq{background-color:white;border:1px solid #e2e2e2;width:calc(100% – 40px);max-width:600px;margin:1.5rem auto 1.9rem;padding:15px;box-sizing:border-box;}@media (min-width:740px){.css-12vbvwq{padding:20px;width:100%;}}.css-12vbvwq:focus{outline:1px solid #e2e2e2;}#NYT_BELOW_MAIN_CONTENT_REGION .css-12vbvwq{border:none;padding:10px 0 0;border-top:2px solid #121212;}.css-12vbvwq[data-truncated] .css-rdoyk0{-webkit-transform:rotate(0deg);-ms-transform:rotate(0deg);transform:rotate(0deg);}.css-12vbvwq[data-truncated] .css-eb027h{max-height:300px;overflow:hidden;-webkit-transition:none;transition:none;}.css-12vbvwq[data-truncated] .css-5gimkt:after{content:’See more’;}.css-12vbvwq[data-truncated] .css-6mllg9{opacity:1;}.css-qjk116{margin:0 auto;overflow:hidden;}.css-qjk116 strong{font-weight:700;}.css-qjk116 em{font-style:italic;}.css-qjk116 a{color:#326891;-webkit-text-decoration:underline;text-decoration:underline;text-underline-offset:1px;-webkit-text-decoration-thickness:1px;text-decoration-thickness:1px;-webkit-text-decoration-color:#326891;text-decoration-color:#326891;}.css-qjk116 a:visited{color:#326891;-webkit-text-decoration-color:#326891;text-decoration-color:#326891;}.css-qjk116 a:hover{-webkit-text-decoration:none;text-decoration:none;}Wealthy nations have argued that the waiver alone will not produce vaccines, given that most developing countries lack technologies or other capabilities to manufacture them.“Too much energy is being spent on an initiative that won’t provide immediate relief,” Gary Locke, the Commerce Department secretary and ambassador to China during the Obama administration, wrote on Sept. 8.He said the issue had become politicized: “But it won’t get shots into arms when people really need it — which is right now.”Health experts have blamed the ban on vaccine exports from India, imposed in April, for stunting the global supply. Two months later, the Serum Institute of India, the world’s largest vaccine maker, announced that it would divert its AstraZeneca vaccine production to domestic needs after a second wave of infections devastated India, reneging on hundreds of millions of doses that were designated for poor countries.Egypt started manufacturing China’s Sinovac vaccine with the aim of making one billion doses per year.Khaled Desouki/Agence France-Presse — Getty ImagesThe Biden administration has been pressuring Prime Minister Narendra Modi of India to drop the ban, and on Monday, as the annual U.N. meeting opened, India’s health minister announced that Covid-19 vaccine exports would resume in October.Mr. Modi, along with the leaders of Japan and Australia — members of the so-called Quad countries — will attend a meeting at the White House on Friday, two days after the president’s vaccine summit.Senior American and E.U. officials also met in Washington on Monday, to discuss what several officials described as continued efforts to increase vaccine manufacturing.That will be all the more necessary as the United States and other countries begin recommending booster shots; Israel is already offering them to anyone older than 30. The World Health Organization had asked wealthy countries to hold off on administering booster shots to healthy patients, until at least the end of the year, as a way of enabling other nations to vaccinate at least 40 percent of their populations.Dr. Anthony S. Fauci, the president’s top medical adviser for the coronavirus, said in an interview that the Biden administration was working on a far-reaching global response plan, but he would not offer specifics. Building additional vaccine manufacturing plants may be a reasonable step to prepare for the next pandemic, he said, but that cannot happen quickly enough to end this one.“We’re trying to figure out what is the best way to get a really fully impactful program going,” Dr. Fauci said. “We want to do more, but we’re trying to figure out what the proper and best approach is.”