The US Centers for Disease Control and Prevention (CDC) is urging domestic travelers in the US to test for COVID-19 before and after they travel, even if they're vaccinated.

The health agency is asking travelers to consider getting tested for current infection using either a PCR or antigen test as close to the time of departure as possible, and no more than three days before they travel. This comes ahead of Memorial Day Weekend, as millions of Americans are expected to travel for the unofficial start of summer. 

The recommendation is in place because cases and hospitalizations are rising in the US. The agency also recommends that travelers are are up-to-date with their vaccines before travel, and check their destination’s virus situation before traveling. Travelers are urged not to travel if they have symptoms, have tested positive for COVID-19, are waiting for results of a test or have had close contact with a person with COVID-19 and are recommended to quarantine.

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The US government is no longer enforcing a transportation mask mandate
The US government is no longer enforcing a transportation mask mandate © ferrantraite / Getty Images

Do domestic travelers have to wear masks?

On April 18, a court order requiring masks on public transportation conveyances and at transportation hubs was scrapped. The CDC continues to recommend that people wear masks in indoor public transportation settings at this time. While it will not enforce mask-wearing as a result, it recommends that passengers aged two years or older should wear a well-fitting mask or respirator in indoor areas of public transportation and transportation hubs, especially in locations that are crowded or poorly ventilated, such as airport jetways.

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Why are vaccinated travelers advised to test pre-travel?

The CDC says that while COVID-19 vaccines are effective at preventing infection, serious illness and death, some people who are fully vaccinated will still get the condition as vaccines are not 100% effective at preventing infection. Travelers who are up-to-date with their vaccines may feel well and not have symptoms, but still can be infected and spread the virus to others. An infection of a fully-vaccinated person is referred to as a “vaccine breakthrough infection."

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Masks on planes are now optional
Masks on planes are now optional © Damircudic / Getty Images

Why should domestic travelers test after travel?

The CDC recommends that travelers test for current infection with a viral test if their travel involved situations with greater risk of exposure, such as being in crowded places while not wearing a well-fitting mask or respirator. The reason is that they might have been exposed to COVID-19 on their travels, and while they might feel well and not have any symptoms, they can still be infected and spread the virus to others.

For more information on COVID-19 and travel, check out Lonely Planet's Health Hub.

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