A spokesperson for New York City Health + Hospitals says workers in public hospitals and city-run clinics who are not vaccinated will need to take weekly COVID-19 tests beginning next month.

Mayor Bill de Blasio is expected to make a formal announcement on Wednesday.

New York’s seven-day positivity has grown to 1.72% There's an ongoing conversation over the possibility of a return to mask-wearing as health officials continue to push hard for vaccinations.

Health officials fear the current spike in the city’s COVID-19 positivity rate may be due to the highly contagious delta variant. City data shows more than 400 confirmed cases in the last seven days, a slight upward trend, though deaths and hospitalizations are still decreasing.

According to Centers for Disease Control and Prevention Director Dr. Rochelle Walensky, “The delta variant now represents 83% of sequenced cases. This is a dramatic increase, up from 50% for the week of July 3. In some parts of the country, the percentage is even higher, particularly in areas of low vaccination rates."

As the city looks forward to the upcoming start of the school year, the city's universal policy on mask wearing for both vaccinated and unvaccinated children has become a point of contention for some. The mayor said Tuesday that he's also expecting to see a large vaccination push among students 12 and up before September.

"I think you're going to see a lot of parents whose kids were not in person in school who are coming back into school in September who are going to feel very natural about saying, ‘I want to get my kid vaccinated ahead of that.'"