By September, as deaths from COVID-19 passed 1,000 per day, it was clear that the United States was indeed experiencing "a pandemic of the unvaccinated," as Rochelle Walensky, director of the Centers for Disease Control and Prevention, called it in July. Hospitals were reporting that nearly all patients filling their ICU beds were unvaccinated, and tracking data showed that only 64% of the U.S. population had received at least one dose of vaccine-an indication that resistance to vaccination persists in pockets of the population. Surprisingly, nurses and other medical workers are included in these groups.

The main reasons cited by people, including health care workers, who are unsure about or opposed to vaccination, are possible serious side effects and unease with the rapidity of COVID-19 vaccine development. Some health care workers also object to mandates-institutional or government-that compel hospital and clinical staff to get vaccinated or lose their jobs. Others cite possible adverse effects on fertility-a discredited claim that continues to circulate on social media.

A survey by the American Nurses Association (ANA) found that unvaccinated nurses' top concerns were safety, including uncertainty about the vaccines' long-term effects, and mistrust of the vaccine development and approval process. On August 23, the U.S. Food and Drug Administration (FDA) formally approved the Pfizer vaccine; previously it had been given emergency use authorization. Following the FDA action, many hospitals and health care providers moved from urging vaccination to mandating it for all staff. It remains to be seen if the 11% of nurses still resisting vaccination (per the ANA survey) are persuaded by the FDA action and employer mandates to change their minds.-Frank Brodhead