From front, registered nurses Megan McLaughlin and Amy Wells join pharmacist Claudia Corona-Guevara in drawing shots of Johnson & Johnson COVID-19 vaccine in the pharmacy of National Jewish Hospital for distribution early Saturday, March 6, 2021, in east Denver. Volunteers worked with nurses and physicians from National Jewish to administer 2,500 vaccinations of the Johnson & Johnson vaccine that requires a single shot instead of two like the other vaccines. David Zalubowski/AP Photos