WASHINGTON, Dec.19 (Reuters) – U.S. health officials on Sunday urged Americans to get vaccinated, wear masks and be careful if they travel during winter break as the Omicron variant raged across the country. world and was set to take over as a dominant strain in the United States.

The government is preparing for the next phase of battle in a two-year struggle against a virus that has killed 800,000 people and disrupted all aspects of daily life.

Dr Francis Collins, director of the National Institutes of Health, told CBS ‘Face the Nation that the number of Omicron cases will rise sharply over the next two weeks.

“A big message for today is that if you have received vaccines and a booster you are very well protected against Omicron which is causing you serious illness. have not yet obtained one: this is the week to do so. Don’t wait, ”he said.

Omicron is multiplying rapidly, making COVID-19 vaccinations and booster shots more crucial than ever, White House chief medical adviser Dr Anthony Fauci said on Sunday. Currently, 27% of U.S. residents have not even received a single dose of the vaccine, according to the Centers for Disease Control and Prevention.

“It’s just, you know, raging in the world,” Fauci, director of the National Institute of Allergy and Infectious Diseases, told NBC’s “Meet the Press” show.

Omicron has been found in 43 of 50 US states and approximately 90 countries to date.

New York State recorded 22,478 positive COVID-19 cases on Saturday, Governor Kathy Hochul says tweeted on Sunday, marking the state’s third daily record for new positive cases in three days.

U.S. Senator Elizabeth Warren said on Sunday that she had tested positive for COVID-19 but was showing only mild symptoms.

The Democrat of Massachusetts, 72, said on twitter she is vaccinated and boosted and tested regularly for COVID-19, and “while I tested negative earlier this week, today I tested positive with a breakthrough case.”

She said she was “grateful for the protection provided against serious illnesses resulting from the vaccination and the booster”.

The number of cases doubles in 1.5 to 3 days in areas of community transmission, the World Health Organization said on Saturday.

In parts of the United States, 50% of genetically sequenced COVID tests have detected the Omicron variant, Fauci told CNN, “which means it’s going to take over.”

The virus is forcing sports teams to reschedule matches and entertainment venues to cancel shows. The National Basketball Association postponed five more games on Sunday.

In New York City, Mayor Bill de Blasio urged residents to get vaccinated or receive a booster and said the city would spend $ 10 million on an advertising campaign to promote the recalls.

Colorado Governor Jared Polis, meanwhile, told NBC he plans to change the definition of fully immunized in his state from two to three. “I wish they’d stop talking about it as a booster. It’s really a three-dose vaccine,” he said.

BOOSTERS, TESTS, SURGE TEAMS

President Joe Biden plans to give a speech Tuesday on the increase in COVID cases, hammering out his message to unvaccinated Americans to get vaccinated and to those who are vaccinated to receive a booster.

Part of Biden’s strategy is to focus on increasing testing, Fauci told CNN’s “State of the Union”.

“We really need to flood the testing system. We have to have tests available for anyone who wants them,” he said.

Hospitals in parts of the country are already strained by COVID patients and things are likely to get worse, health officials said.

“The government is now ready to start sending much needed response teams to the places that are really hard hit and the president will have more to say about that in a speech on Tuesday,” Collins said.

Neither Fauci nor Collins have urged vaccinated Americans to cancel travel plans – just to wear a mask at all times at airports, on planes, trains and buses.

“I’m not going to say you shouldn’t travel, but you should be doing it very carefully,” Collins said.

Reporting by Doina Chiacu and David Brunnstrom; Additional reporting by Nathan Layne in Wilton, Connecticut; Editing by Lisa Shumaker and Daniel Wallis

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