The TSA said it screened nearly 1.3 million travelers on Sunday, the most since the beginning of the pandemic

• The Transportation Security Administration screened 1,284,599 people in airports nationwide on Sunday, according to spokesperson Lisa Farbstein, the most since the COVID-19 pandemic's start.
• Sunday was also the sixth day in the last 10 that the TSA screened more than 1 million travelers.
• More than 63,000 Americans died of COVID-19 in December, making it the deadliest month of the pandemic.
• Anthony Fauci said the pandemic "might actually get worse" over the next few weeks due to high holiday travel.

The Transportation Security Administration screened nearly 1.3 million people the Sunday after Christmas.

The TSA said the agency screened 1,284,599 people in airports nationwide, the highest number of passengers since the pandemic hit, on Sunday, December 27. Sunday was also the sixth day in the last 10 that the TSA screened more than one million travelers.

"If you choose to travel, please wear a mask," TSA spokesperson Lisa Farbstein said in a tweet Monday morning.

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The Centers for Disease Control and Prevention recommended Americans stay home this holiday season to slow the spread of COVID-19. More than 63,000 Americans died of COVID-19 in December, making it the deadliest month of the pandemic.

A record 120,151 Americans were currently hospitalized with COVID-19 as of Christmas Eve, per data from the COVID Tracking Project. The CDC said the US has recorded nearly 19 million total cases as of December 28.

The busy holiday travel season could heighten the COVID-19 spread and overwhelm hospitals. Healthcare workers said they expect the surge to get worse following Christmas and New Year's, which many say will lead to increased burnout. Anthony Fauci said the pandemic "might actually get worse" over the next few weeks due to high holiday travel.

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California is already experiencing the consequences of an uncontrolled outbreak. The state enacted a stay-at-home order this month in some areas after reaching high intensive care capacity. Southern California reported 0% available ICU beds prior to Christmas, forcing some hospitals to put gurneys in gift shops.

Vaccines can offer protection, and the CDC said the US inoculated 1 million people so far. But a majority of Americans must get vaccinated before the country reaches herd immunity, Fauci said, and researchers at the University of Washington said masks will prevent more COVID-19 deaths than vaccines before April.