• Two mutated strains of the highly transmissible omicron variant of Covid-19 are the main culprits behind a "rising tide" of infections in New York, Gov. Kathy Hochul said.
• State health experts have seen no evidence that the new strains are more severe than others, and so far they are not expecting a repeat of last winter's surge in cases.
• New York will also keep in place its mask requirements for public transit and other similar settings, at least for now.

Two mutated strains of the highly transmissible omicron variant of Covid-19 are the main culprits behind a "rising tide" of infections in New York, Gov. Kathy Hochul said Wednesday.

"We did identify two subvariants of omicron, which is driving the current spike in cases," Hochul said during a press event in Syracuse.

"We're taking this very seriously," the Democratic governor said. "You don't know, every single variant that comes, is it going to be worse than the last one?"

But Hochul stressed that state health experts have seen no evidence that the new strains are more severe than others, and so far they are not expecting a repeat of the massive, omicron-fueled surge in cases last winter.

"We're not panicking about this, we're not changing, but we also want to make sure that we're smart about this," she said.

New York's data currently shows 40 Covid cases per 100,000 people, which Hochul said is a more informative measure to follow than the total infection rate. The governor noted that while that figure was "quite a bit lower" in recent weeks, the current level is significantly below the winter peak of 461 cases per 100,000 people.

"We're a long way from that peak, but I don't even want to get close to that peak," she said.

Across the U.S., cases are nowhere near the pandemic peak of about 808,000 new cases a day that were reported in mid-January. New infections are currently averaging about 35,000 a day, according to a CNBC analysis of data compiled by Johns Hopkins University. While that is a fraction of the peak, cases have started edging up nationwide in recent weeks and some areas of the country are seeing localized surges.

Statewide, there are about 1,400 people hospitalized with Covid, Hochul said. Near the pandemic's peak, 12,000 people in New York were hospitalized with the virus, she said.

The number of hospitalizations, which have been a key data point in the state's response to the health crisis, are even more crucial to monitor, with the prevalence of at-home testing for Covid clouding total testing figures, the governor said.

She also said that about half the cases of people hospitalized with Covid are people who were admitted for other reasons, and then tested positive once they arrived.

On the plus side, the warming weather should play a part in slowing the spread of infections, Hochul said, because more people will socialize outdoors rather than in confined spaces.

New York also will keep in place its mask requirements for public transit and other similar settings, at least for now. "Let's just be smart about it," Hochul said.

That decision comes two days after a federal judge's ruling struck down the mask mandates for public transportation that had been issued by the U.S. Centers for Disease Control and Prevention. The Biden administration has said it will appeal that ruling if the CDC deems a mask mandate remains a public health necessity.

Philadelphia became the first major U.S. city on Monday to reinstate its Covid-19 mask mandate for indoor activities as the highly contagious omicron BA.2 subvariant drives new Covid cases higher across the U.S.

Hochul said if it weren't for the new subvariants, "I suspect we would have been able to say goodbye to masks in all settings. But we're going to get there. We will get there."