Reactions were largely supportive of vaccine restrictions imposed Tuesday by Mayor Bill de Blasio of New York City, the most stringent steps announced recently in any major U.S. city, though some health experts suggested they might not go far enough. Workers and customers in New York will soon have to provide proof that they have received at least one vaccine dose before engaging in activities like indoor dining, exercising in gyms and seeing performances, Mr. de Blasio said on Tuesday.
The new requirements could have been rolled out sooner, some health experts said, and vaccination and mask requirements could be further expanded.
Still, the new restrictions got a positive response from one important trade group, the N.Y.C. Hospitality Alliance, which represents restaurants and bars, a sector still recovering from months of limited capacity and other restrictions.
Andrew Rigie, the trade group’s executive director, said that the new restrictions could avert another broad lockdown. The rules, he said, “may prove an essential move to protecting public health and ensuring that New York City does not revert to restrictions and shut down orders,” he said in a statement.
At the White House, the press secretary Jen Psaki said the Biden administration supported local efforts to control the virus.
“Different communities and states are going to take steps to protect the people living in their states, and also incentivize, whether it’s through carrots and sticks, more people getting vaccinated,” Ms. Psaki said at a news conference. The federal government, she said, has no plans to issue similar guidance on a national level.
Later in the afternoon, President Biden reiterated the point, saying he thought that more cities and states should announce rules like New York City’s.
Mr. de Blasio said the program will start on Aug. 16, and that enforcement will begin on Sept. 13, when schools are expected to open and more workers could return to the office.
Dr. Wafaa El-Sadr, an epidemiology professor at Columbia University, said that she wished the mayor had imposed the restrictions earlier and that she did not see the point in further delaying them.
“Once vaccination was widely available to people, which was weeks ago, I think requiring vaccination for access to such venues would have been appropriate,” Dr. El-Sadr said.
The city’s vaccination program has slowed in recent months, despite efforts like a $100 payment to people who get vaccinated and inoculating people at home.
Fully vaccinated people are protected against the worst outcomes of Covid-19 caused by the Delta variant, but there’s a sharp drop in the efficacy if an individual has only had one dose of a two-dose vaccine.
Dr. Celine Gounder, an epidemiologist at New York University’s Grossman School of Medicine and an adviser to city officials, also recommended that city officials expand their message about the importance of masking and testing, even for vaccinated people, noting that “we can walk and chew gum at the same time.”
About a week ago, the federal government updated its health guidance, recommending that people wear masks indoors in virus hot spots even if they are vaccinated.
Mr. de Blasio said on Monday that he strongly recommended that people wear masks indoors, but that he would not immediately impose a requirement in the city, as many municipalities have.