The contrast could hardly be sharper. n much of the developed world, vaccine orders are soaring into the billions of doses, Covid-19 cases are easing, economies are poised to roar to life and people are busy lining up summer vacations. In many less developed nations, though, the virus is raging on, sometimes out of control, while vaccinations are happening far too slowly to protect even the most vulnerable.

That split screen — clubs and restaurants reopening in the United States and Europe while people gasp for oxygen in India — was never supposed to be so stark. Some 192 countries signed up last year for Covax, a vaccine-sharing partnership, and the Gates Foundation poured $300 million into an Indian factory to make doses for the world’s poor. The European Union’s top executive told a global summit last June: “Vaccination is a universal human right.”

But the virus is spreading more rapidly than ever, driven largely by gains in South America and India, and the campaign to vaccinate the world is floundering.

India, an important source of vaccines in normal times, has halted exports as it fights a record surge in the virus and an expanding humanitarian crisis. That has delayed critical shipments, with India making the majority of Covax supplies.

In Brazil, where thousands are dying daily, officials have received only a 10th of the AstraZeneca doses they were promised by midyear.

And in countries as varied as Ghana and Bangladesh, which blew through their initial vaccine supplies, the lucky few who received a first shot have been unsure of when they will receive another.

“It’s a moral issue,” said Boston Zimba, a doctor and vaccine expert in Malawi, which has vaccinated only 2 percent of its people. “This is something rich countries should be thinking The problems go well beyond the availability of vaccines to deep-seated logistical problems and vaccine hesitancy, an inheritance with roots in the colonial and imperial eras.