‘Use common sense’

New Jersey is seeing a spike in COVID-19 cases not seen since the start of the year.

Health Commissioner Judy Persichilli said during a news conference alongside Gov. Phil Murphy this week that the surge is most likely due to the delta and omicron variants.

The omicron variant, though, accounts for a small percentage of overall cases so far in the state, she added. In one hospital chain, about 13% of positive tests were omicron, Persichilli said, which is in line with Centers for Disease Control and Prevention expectations.

There were just over 6,500 confirmed cases reported on Monday, nearly matching the level in January when cases spiked to their highest point in the outbreak.

Over the past two weeks, the rolling average number of daily new cases has increased by about 2,394, an increase of nearly 66%, according to Johns Hopkins researchers.

Much about the omicron coronavirus variant remains unknown, including whether it causes more or less severe illness.

Scientists say omicron spreads even easier than other coronavirus strains, including delta, and it is expected to become dominant in the U.S. by early next year.

Early studies suggest the vaccinated will need a booster shot for the best chance at preventing an omicron infection but even without the extra dose, vaccination still should offer strong protection against severe illness and death.

Murphy, a Democrat, said that if the CDC changes its definition of fully vaccinated to include a booster shot, then the state would most likely follow suit. Under Murphy’s orders, teachers, state workers and other public employees must either be fully vaccinated or undergo regular testing.

The governor declined to say whether he would reinstate indoor mask mandates and limit capacities inside, but said he was inclined to lean toward implementing them if they could save lives.

With Christmas coming up, he urged residents to get boosted. He urged people to wear masks inside if not everyone has been vaccinated or if their status is unclear. He boiled down his overall advice about holiday get-togethers to a few words.

``Use common sense,’’ he said.