Worldwide vaccine inequality threatens to unleash the next COVID-19 variant

•Significant inequities remain in COVID-19 vaccine distribution and vaccination rates worldwide.•Worldwide COVID-19 vaccine distribution is complicated by supply, logistics, and vaccine hesitancy.•Recent COVID-19 variants have emerged from regions with low vaccination rates, such as Africa.•Higher income nations must address vaccine inequality to avert the next major COVID-19 variants. The emergence of the Omicron variant (B.1.1.529 BA.1) near Johannesburg heralded the development of an unprecedented number of new COVID-19 infections across South Africa in November 2021. Omicron and its subvariants would soon become the dominant strains across Africa, Europe, and the United States. As with the Delta variant (B.1.617.2), Omicron emerged from an industrialized nation with one of the lowest vaccination rates of any well-developed country. The emergence of variants from undervaccinated regions is a direct consequence of the virus replicating unchecked through an unprotected population. Despite this, the United States and other higher-income nations have adopted a strategy of preferentially inoculating their citizens with multiple and booster doses, whereas lower-income nations struggle with vaccine availability, infrastructure, and their own vaccine manufacturing capability. Much more needs to be done to address worldwide vaccine inequities and prevent the emergence of the next devastating variant. The persistence of the pandemic anywhere remains an ongoing threat to citizens everywhere.