Editor's note: An updated version of this story is available here.
Many destinations are adding testing requirements for travelers from the United States, but that doesn’t mean travelers should go running off to the nearest lab for a test that can be expensive or difficult to schedule.
Some destinations, including Hawaii and Bermuda, accept self-tests that can be taken outside a lab, whether that's at home or at a hotel. Select home tests can be purchased at local retailers and pharmacies, and results can often be processed within minutes.
Not all self-tests will meet a destination's requirements for entry, but they can be a useful option for travelers who are worried about a shortage of coronavirus test appointments at local pharmacies.
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From pricing to accuracy, here's what travelers should know about at-home testing.
Can travelers returning to the U.S. use self-tests?
The Centers for Diseases Control and Prevention requires international air travelers who have not recently recovered from COVID-19 to take a viral test no more than three days before entering the U.S. That includes return trips for U.S. citizens and permanent residents.
Travelers can use a self-test, but the test needs to meet a number of criteria:
It must be either a nucleic acid amplification test (NAAT) or antigen test.
The test must have emergency use authorization from the U.S. Food and Drug Administration.
Testing must include remote supervision from the manufacturer through a video call so the telehealth proctor can confirm that the person’s identity and test results. Some home tests also require a prescription.
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The FDA has granted emergency use authorization to nearly a dozen home tests, but not all offer a telehealth proctor or quick results. The testing options that are suited to international travelers entering the U.S. include:
Abbott’s BinaxNOW COVID-19 AG Card Home test (note: the company’s BinaxNOW antigen self test, which is available over the counter, is not eligible for travel purposes).
How do at-home tests work?
At-home tests are used to detect current infections, but the testing methods vary between brands.
Some require a nasal swab, while others ask for a sample of saliva. For both types of tests, the CDC suggests people wash their hands with soap, clean the surfaces where the testing will take place, check the expiration date before use, and follow instructions carefully.
Some tests will need to be taken multiple times. Abbott’s BinaxNOW self-test, for instance, has users swab their lower nostrils and check the results two times within three days.
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How much do the tests cost?
A six-pack of the BinaxNOW home test can be purchased on eMed for $150, or as a two-pack for about $70 through Optum. The test is not available over the counter, and travelers should note that deliveries within the U.S. may take up to five business days.
The Ellume home test is available at select pharmacies and retailers; the cost is $35 to $45 per test.
With the delta variant causing an increase in COVID-19 cases in the U.S., growing demand for testing means home tests are out of stock at some retailers.
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How accurate are at-home tests?
Health experts say at-home antigen tests are not as accurate as PCR tests, which are often tested in a lab and can take hours to process.
Several customers who purchased the Ellume tests have complained on consumer review boards about "false positive" results when compared with laboratory-based PCR tests, USA TODAY reported.
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Do all destinations with testing requirements accept at-home tests?
Travelers should check the entry requirements for each destination country or state. Some countries do accept select rapid antigen self-tests, including Portugal and Bermuda.
Does Hawaii accept at-home tests?
Unvaccinated vacationers will have to show proof of a negative coronavirus test to enter Hawaii. The state accepts select at-home results provided by the state's testing partners, including:
Costco/AZOVA: The at-home saliva test is available at Costco for travel Thursday through Monday. Those departing on weekends may not receive their results back in time for their flight. Travelers can take the test at home and ship it overnight to a lab, where results should be ready within 12 to 28 hours of arrival. The test costs about $119, according to Costco's website. The store also offers in-pharmacy testing for travelers in select markets.
Vault Health: Travelers 5 and older can take this saliva test at home with real-time supervision via video chat.
Do cruises accept at-home test results?
Testing protocols differ between cruise lines, but some do accept at-home tests.
Royal Caribbean International and Celebrity Cruises accept self-tests that have emergency use authorization and are taken under the supervision of a telehealth proctor. Most guests 2 and older sailing from U.S. ports need to take a coronavirus test no more than three days before arriving at the terminal.
Carnival Cruise Line, Princess Cruises and Holland America Line – all owned by Carnival Cruise Corp. – require guests to present a negative coronavirus test taken within three days of embarkation. Vaccinated guests can use a home test that has emergency use authorization and is taken under the supervision of a telehealth proctor.
Other cruise lines, including Norwegian Cruise Lines, require testing before disembarkation but administer the tests on board.
What happens if my self-test is positive?
If a test comes back positive, the telehealth providers should alert local health officials and advise the infected travelers on what they and their close contacts should do, according to the CDC. That may include a quarantine period.
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Contributing: Ken Alltucker, USA TODAY
Follow USA TODAY reporter Bailey Schulz on Twitter: @bailey_schulz.
This article originally appeared on USA TODAY: What travelers need to know about at-home COVID tests