Long Island had 1,116 people hospitalized with COVID-19 on Saturday,...

Long Island had 1,116 people hospitalized with COVID-19 on Saturday, down from the omicron peak of 2,254 in mid-January. Last June 1, the figure was 125. Credit: NurPhoto via Getty Images

The omicron variant has quickly become the dominant coronavirus strain, making up more than 73% of new infections nationwide, according to the Centers for Disease Control and Prevention. With breakthrough cases driving the surge in cases, here are some frequently asked questions about vaccines and their effectiveness against the new variant.

How much protection do vaccines provide against omicron?

Data from both Pfizer and Moderna show good protection against serious disease when a booster dose is received, according to Dr. Sharon Nachman, chief of Pediatric Infectious Diseases at Stony Brook Medicine.

Dr. Adrian Popp, chair of infectious disease at Huntington Hospital, also said getting a booster makes a significant difference in protection, as initial immunity wanes.

"The level of antibody and cellular immune protection grows up quite high" with a booster dose, he said, "even stronger in terms of number of the level of antibodies than from the initial series" of two doses.

The vaccine's "effectiveness" rate against preventing COVID-19 in all age groups has declined from 81% earlier this month to 75%, according to state data. Adding the booster elevates the vaccine's effectiveness back to more than 80%, even against omicron, experts said.

How protected are you in the two-week period after a booster?

"Probably very protected, and very rapidly as well," Nachman said. The response to a booster is quicker than that of a first or second dose, she said.

Should you wait six months (or two for those who received the one-shot Johnson & Johnson vaccine) before getting a booster?

Both Popp and Nachman said if you are healthy with no past medical history, it should be OK to wait a full six months to get a booster if you received either the Pfizer or Moderna vaccine. Those who are immunocompromised, medically frail or elderly should consider getting one sooner.

Does omicron cause milder sickness than other strains of the virus?

It appears so, according to research. Preliminary data from the U.K. Health Security Agency suggest that people with the omicron variant are between 50% and 70% less likely to need hospitalization than those with the delta strain.

"What we've seen here in New York for the last two weeks or so and the ICU here at Northwell is that omicron is probably less virulent," Popp said. "That is actually a bonanza, to put it that way."

The people still getting severe disease fall into three categories: the unvaccinated, the immunocompromised and the medically frail, Popp said. As of Wednesday, 100% of the COVID-19 positive patients in the ICU at Huntington were unvaccinated, he said. Northwell Health spokeswoman Miriam Sholder could not say how many people that is, but said COVID-19-positive patients comprised 10% of ICU patients at the hospital.

What is the period between exposure and symptoms?

It appears the lag time is about 1 1/2 to three days for the omicron variant versus five to seven days for previous variants, Popp said.

What about treatment for those already infected?

Health care professionals are optimistic about two new options offering treatment for symptoms, when previously prevention through vaccines was the best tool in their arsenal.

The Food and Drug Administration on Wednesday approved Pfizer’s Paxlovid pill to treat early COVID-19 infections. An antiviral pill from Merck was authorized on Thursday, but Pfizer's drug is all but certain to be the preferred option because of its mild side effects and effectiveness.

Do you anticipate the need for a vaccine specifically formulated for omicron?

Although Pfizer has said it could tweak its formula to target omicron and make it available within 100 days, Nachman said she did not think it was immediately necessary.

"The complete series of primary, plus booster, doses seem to be doing their job and keeping serious illness away," Nachman said.

With AP

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