At New York-Presbyterian Morgan Stanley Children’s Hospital, one of the most highly regarded hospitals in New York City, a rumor spread last week that the line for the coronavirus vaccine on the ninth floor was unguarded and anyone could stealthily join and receive the shot.

Under the rules, the most exposed health care employees were supposed to go first, but soon those from lower-risk departments, including a few who spent much of the pandemic working from home, were getting vaccinated.

The lapse, which occurred within 48 hours of the first doses arriving in the city, incited anger among staff members — and an apology from the hospital.

“I am so disappointed and saddened that this happened,” a top executive at NewYork-Presbyterian Morgan Stanley Children’s Hospital, Dr. Craig Albanese, wrote in an email to staff, which was obtained by The New York Times. ...

A team of British scientists released a worrying study on Wednesday of the new coronavirus variant sweeping the United Kingdom. They warned that the variant is so contagious that new control measures, including closing down schools and universities, might be necessary. Even that may not be enough, they noted, saying, “It may be necessary to greatly accelerate vaccine rollout.”

LONDON — As nation after nation rushed this week to close their borders with Britain, the moves brought back memories of the way the world reacted after the coronavirus first emerged broadly in the spring. Most of those initial travel prohibitions came too late, put in place after the virus had already seeded itself in communities far and wide.

This time, with countries trying to stop the spread of a new, possibly more contagious coronavirus variant identified by Britain, it may also be too late. It is not known how widely the variant is already circulating, experts say, and the bans threaten to cause more economic and emotional hardship as the toll wrought by the virus continues to grow.