About 40% of the Americans killed by COVID-19 have been residents of nursing homes. Many of the deaths occurred during the early weeks of the epidemic, before the need for extraordinary long-term care safeguards was apparent. Many others were the result of wrongheaded action by public officials.

In some states, new cases are popping up in nursing homes. More of the very people who should have been able to rely in an additional layer of protection will die.

As the coronavirus remains a threat, it creates a larger community pool of infected people, from which the virus can be transmitted into our long-term care facilities. They have to be staffed, after all, and that means anything outside the walls of a nursing home can be taken inside.

That leaves it up to nursing home administrators and staff, along with local and state governments, to erect barriers against the disease. The most effective is bans on visitors to nursing home residents. Another helpful step is frequent testing of both nursing home residents and staff. We know area nursing homes are being vigilant. They must remain so.