As coronavirus cases and test positivity in the city continue to rise rapidly, Mayor Bill de Blasio at a press briefing on Thursday announced a series of measures to expand testing and mask availability, as well as urge residents to get vaccinated and seek booster shots. 

Health experts have linked the rising cases, which have led to crushing demand for tests in the five boroughs, to the omicron variant. Dr. Dave Chokshi, the city health commissioner, said that at the beginning of the week, 13% of city cases were caused by omicron, and that the variant will likely take over as the most common variant in a matter of weeks. 

The city will open five new testing sites and add more mobile testing vans around the city, and existing city testing sites will now be open seven days a week. The city will also make at-home rapid testing kits available at all city-run sites to avoid long lines, said Dr. Ted Long, who runs the city’s Test and Trace program. 

The city will also distribute 500,000 at-home rapid tests and 1.5 million KN-95 medical grade face masks through community organizations around the city, beginning on Monday. 

De Blasio said that the city will also launch a media campaign urging all residents over 16 years old to get booster shots, and will increase inspections at city businesses to expand enforcement of vaccination requirements for restaurants, gyms and entertainment venues, as well as of the state mask mandate in businesses. 

The new measures to push back on the coronavirus comes as city cases are growing exponentially, pushing to 4,000 daily cases, levels the city hasn’t seen since early April. 

Test positivity has more than doubled just this week, according to city testing data. 

“It’s an urgent situation,” de Blasio said, “because what we know so far is imperfect about omicron, but it sure is clear that it spreads fast.”

Chokshi said that he understood that many people feel “pandemic fatigue” as the virus enters yet another wave in the city, throwing a wrench into holiday plans. 

“I get it,” Chokshi said. “But unfortunately, this virus is not yet tired of us.”

Even as cases have grown, hospitalizations have risen at a much smaller rate, and deaths due to COVID-19 have remained essentially flat since August, city data show. 

Those data show that the city’s vaccination effort has worked to reduce instances of severe COVID-19, health experts said Thursday. 

Chokshi emphasized that the rise of the omicron variant makes booster shots even more important for preventing infection, saying that available scientific data about the variant indicate that vaccination can reduce the likelihood of severe disease. 

“The facts are very clear,” Chokshi said. “Each new variant makes it more important to get vaccinated rather than less important.”

Long called on residents to urge their relatives and friends to get booster shots before the holidays. 

“My dad’s coming for Christmas,” Long said. “I'm not letting him through the door unless he gets the booster.”

The increased emphasis on testing and mask wearing comes after de Blasio and his top health aides have for months said that vaccination was a higher priority. Last month, de Blasio expanded his administration’s series of vaccination mandates to include all private businesses in the city, starting Dec. 27. 

“I never want to give people the impression that wearing a mask is a substitute for vaccination,” de Blasio said at a November news conference. 

The city expanded its mobile testing fleet from 40 vans to 70 last month, but had maintained reduced hours at its brick-and-mortar sites from the summer, before the beginning of the delta wave in the city, according to Denis Nash, an epidemiologist at the CUNY School of Public Health. 

Since the summer, Chokshi has maintained non-binding guidance that city residents wear masks indoors, and he reemphasized that guidance last month. Gov. Kathy Hochul instituted a temporary mask mandate for the entire state last week. 

“What we need to do is not rocket science,” Chokshi said. “We have the interventions that we know have worked.”