More coronavirus tests will be available in January, Fauci says, as the U.S. struggles with a shortage

The United States will have an ample supply of coronavirus tests next month, according to Anthony Fauci, the nation’s top infectious-disease expert and chief medical adviser to President Joe Biden, as people across the nation seeking them face long lines and empty shelves.

Testing will be "very important" as the country deals with a surge of cases from the omicron variant, Fauci said Sunday on ABC's "This Week." But the nation is experiencing a shortage of tests as cases increase and people travel for the holidays.

"We've obviously got to do better," Fauci said. "I think things will improve greatly as we get into January, but that doesn't help us today and tomorrow."

The Biden administration, which last week announced a plan to offer 500 million at-home tests to Americans sometime next month, has faced criticism in recent days over its failure to prepare an adequate supply of tests.

"I don't think anybody anticipated that this was going to be as rapidly spreading as it did," Biden said Tuesday of the omicron variant.

But the same day, the director of the Centers for Disease Control and Prevention, Rochelle Walensky, said officials had been "working hard as we anticipated this, because we knew that omicron had this capacity to increase at this rate."

People who are able to find at-home rapid tests in stores may face a limit on how many they can purchase — reminiscent of shortages of items like toilet paper earlier in the pandemic. Walgreens stores have placed a four-item limit on tests.

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Some medical centers are asking people who test positive with at-home tests not to come to an emergency room unless they are experiencing severe symptoms, citing a rush of asymptomatic people seeking to confirm their at-home results with laboratory tests.

People who test positive with at-home antigen test kits should contact a doctor to report the result and consider taking a lab-based PCR test to verify it, experts advise. In general, antigen tests are less sensitive than molecular tests and tend to work better for symptomatic people.

To increase confidence in a negative test, experts recommend testing frequently at regular intervals, known as “serial testing.”