(Bloomberg) -- The New York City Health Commissioner on Friday issued a health advisory urging residents to mask up in public indoor and crowded outdoor settings.

The move comes as the city experiences “unusually high concurrent spikes” in Covid-19, flu and RSV, the health department said in a statement. 

Cases of Covid-19 have been rising steadily in New York since Thanksgiving, according to city data, though they remain far below the levels reached during the height of the omicron wave in early 2022. The US Centers for Disease Control and Prevention lists all five New York City boroughs as having a high level of infection risk.

The advisory “is especially important for people who are – or are meeting – those who are at increased risk for complications from Covid-19, RSV, or the flu, such as those age 65 and older and people who are immunocompromised.” 

“The holiday season is about togetherness and there is a way to gather safely – even as respiratory viruses in our city are unusually high,” said Health Commissioner Ashwin Vasan. 

He also urged New Yorkers to get jabs for Covid-19 and the flu, even if they have been vaccinated previously.  

With no force of law, the advisory is likely to do little to change behavior in a city accustomed to months of going mask-free. While some masks can be seen on people riding the subway or shopping in crowded stores, they’re no longer mandatory on transit systems or in schools.

Meanwhile, Bloomberg News reported this week that the city is closing its pandemic response lab, a much-vaunted effort to increase testing capacity at the height of Covid. Fewer than 1 million Covid tests were performed by laboratories in the city last month, according to state data, down from 4.6 million in January.

Read More: NYC’s Pandemic Response Lab to Close as Covid Testing Plummets

(Updates with more details throughout.)

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