If you're not vaccinated, you shouldn't travel over the long Labor Day weekend.

That's the bottom line, according to the Centers for Disease Control and Prevention Director Dr. Rochelle Walensky.

"First and foremost, if you are unvaccinated, we would recommend not traveling," Walensky said at a White House COVID-19 briefing on Tuesday.

Since the start of the pandemic, holiday weekends, when many Americans traditionally travel, have been a special concern for health officials because they increase the chances that the virus can spread widely and quickly.

Last year, before vaccines were available to the public, the Transportation Security Administration (TSA) screened more than 3 million airline passengers over the Labor Day holiday.

However, despite the wide availability of vaccines this year, the coronavirus delta variant and an unwillingness on the part of many Americans to get vaccinated has caused a major spike in infections and hospitalizations.

Speaking at Tuesday's briefing, White House COVID-19 Response Coordinator Jeff Zients said that ahead of Labor Day weekend, "it's critical that being vaccinated is part of their pre-holiday checklist."

If you are not fully vaccinated and decide to travel within the U.S. anyway, the CDC recommends that you take the following precautions:

"People who are fully vaccinated, and who are wearing masks, can travel," Walensky said. "Although, given where we are with disease transmission right now, we would say that people need to take these risks into their own consideration as they think about traveling."

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