The International Monetary Fund has estimated that about one billion vaccines could be donated this year, although countries will give priority to their citizens. Another billion vaccine doses could be made by early next year, which should help reduce sudden risks, such as the emergence of new variants of coronavirus that will require revaccination.

Without an immediate response, many developing countries and young market economies may have to wait until the end of next year or even longer to bring the pandemic under control, the authors warn.