An unvaccinated worker at a Kentucky nursing home set off a coronavirus outbreak in March among staff and residents, even among the vaccinated, according to a CDC report released Wednesday. Nearly four dozen were infected—26 residents and 20 employees—and two people died, including one person who had been inoculated against the virus; 22 of those infected had already been vaccinated, and most did not develop symptoms or require treatment. The vast majority of the home’s 83 residents—90 percent—had been vaccinated, but only half of the 116 employees had. The study’s authors wrote, “To protect skilled nursing facility residents, it is imperative that health care providers, as well as skilled nursing facility residents, be vaccinated.”