(ACCRA, Ghana) — Ghana received the world’s first delivery of coronavirus vaccines from the United Nations-backed COVAX initiative on Wednesday—the long-awaited start for a program that has thus far fallen short of hopes that it would ensure shots were given quickly to the world’s most vulnerable people. The arrival of 600,000 doses of the AstraZeneca vaccine in the West African country marks the beginning of the largest vaccine procurement and supply operation in history, according to the World Health Organization and UNICEF.