Speaking at a White House COVID-19 Task Force Briefing on Wednesday, U.S. Centers for Disease Control and Prevention (CDC) Director Dr. Rochelle Walensky said that she expected reports of omicron cases in the U.S. to increase in coming days.

She noted that CDC data showed nursing home residents who are fully vaccinated and have received a booster dose have a ten times lower rate of getting infected with SARS-CoV-2 and that case counts are increasing among unvaccinated residents and those who received a primary series without a booster dose.

Approximately 60% of eligible seniors have already received a booster, Walensky added. More than 200 million Americans are fully vaccinated against COVID-19 and more than 55 million have been “boosted.”

While preliminary research and observations – and Walensky herself – have indicated that the omicron could be “mild,” scientists are still working to determine its severity, transmissibility and ability to evade immune protection and vaccines.

On Tuesday, World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus warned against people “dismissing omicron as mild,” telling reporters in Geneva that it is spreading at a rate “not seen with any previous variant.”

Walenksy, the White House and the National Institute of Allergy and Infectious Diseases (NIAID) Director Dr. Anthony Fauci have previously stated that current COVID-19 vaccines are able to offer some protection from the variant.

On Tuesday, Fauci said that booster vaccine regimens work against omicron.

Omicron variant could become dominant COVID variant within weeks: Former CDC director Video

“At this point, there is no need for a variant-specific booster,” President Biden’s top medical adviser said.

“And so, the message remains clear: If you are unvaccinated get vaccinated and, particularly in the arena of omicron, if you are fully vaccinated, get your booster shot,” he stated.

Earlier in the day, White House Deputy Press Secretary Karine Jean-Pierre told reporters aboard Air Force 1 that the American Rescue Plan has the resources to make sure both that people are getting vaccinated and that schools stay open.

“And so, we’re very confident that that’s going to be the case. We’re not going to shut down. We are comforted by the resources and what we have learned and the tools that we have in our tool belt to do that,” she said.

COVID-19 cases are surging in the U.S. this winter. However, the delta variant remains by far the dominant variant across the U.S.