New NYC omicron subvariant wave starting?

New cases of COVID-19 have stopped falling in New York City and the growing share of infections from the BA.5 omicron subvariant could mean the start of a new wave, according to a former top health aide to City Hall.

"This is likely the beginning of a BA.5 wave," Dr. Jay Varma tweeted. "BA.5 was ~17% of cases 2 weeks ago so likely much higher now. Experience from other countries means there will be another big increase in NYC #COVID19 infections, including among those who have had #Omicron in past few months."

Varma, a noted expert on infectious diseases, said whether this new wave will increase hospitalizations and deaths isn't yet clear. But he is concerned about the effects nevertheless.

"At a minimum, can be confident predicting that BA.5 will lead to more days when people are out of work, kids home from school/camp, & more people suffering from #LongCOVID," Varma tweeted.

Varma served as then-Mayor Bill de Blasio's senior adviser for public health from April 2020 through the end of the mayor's term.

The city's COVID alert level is "medium," which means that the current community spread of the virus isn't putting substantial pressure on the health care system. The New York City Health Department continues to urge residents to get vaccinated and boosted, wear a mask in indoor public settings, get tested when exposed or have symptoms, and stay home if ill. 

In the meantime, advisers to the U.S. Food and Drug Administration recommended that the agency call for the distribution of a modified COVID-19 vaccine booster shot in the fall to U.S. residents. The panel debated but didn't endorse a specific booster to fight a virus that keeps spawning new variants. 

Both Pfizer and Moderna have tested updated vaccine shots that are a better match for the omicron variant that surged over the winter. But genetically distinct relatives have replaced that variant. The newest omicron subvariants — BA.4 and BA.5 — make up about half of all U.S. cases, according to the CDC.

With The Associated Press.