A dearth of immunization sites in Cameroon, weak communication and Covid denial in the Democratic Republic of Congo and a syringe shortfall in Kenya are among the hurdles complicating rollouts. In Zimbabwe, which initially raced ahead of many peers, complacency and a perception of omicron as less serious slowed the campaign; long vaccine queues have turned into a trickle.

“Vaccines, we have plenty,” said Agnes Mahomva, coordinator of Zimbabwe’s national Covid taskforce. “It’s now about how people view the vaccines and getting them to take the shots.”…

As many as two dozen nations are struggling to use their doses due to supply-chain obstacles, hesitancy and other factors, according to Seth Berkley, head of the vaccine alliance, Gavi, a key Covax partner.