The global COVID-19 vaccination campaign began nine months ago, and 58% of the world’s population has yet to receive at least one dose.

The big picture: Raw material shortages, complex and costly manufacturing, and vaccine makers’ choices have made it clear the U.S. and its drug companies likely won’t get the poor, unvaccinated parts of the world out of the pandemic — but China might.

The state of play: Wealthier nations have more vaccines than citizens who want them, while poorer countries are facing bleaker timelines for when they can administer first doses.

• The U.S. and other Western countries could vaccinate teenagers and provide booster shots to everyone, and still have 1.2 billion excess doses available to send elsewhere this year, according to a report from analytics firm Airfinity.
• Meanwhile, the global COVAX consortium now anticipates receiving 25% fewer doses than expected due to production problems with the vaccines made by Johnson & Johnson, AstraZeneca and Novavax, as well as export restrictions from a major supplier in India.

The vaccines made by Moderna and Pfizer/BioNTech have proven […]