This paper argues in support of the WHO’s proposal to forego COVID-19 booster shots until 10% of people in every country are fully vaccinated. The Ethical Argument section shows that we save the most lives and ensure the least amount of suffering by allocating doses first to unvaccinated people. It also argues that there is a duty to support decent lives and to promote health equity, which establish that refraining from boosters is a requirement of justice, not charity. The Replies to Objections section answers objections that appeal to pragmatism, nationalism, ownership, scientific advancement, self-interest, semantics and futility. The Conclusion section emphasizes that for now, wealthy nations should not boost vaccinated people’s immunity and should instead send doses to poorer nations where they are most urgently needed.