New Covid cases are rising fast and at-home rapid tests are in high demand.

But consumers scrambling to buy tests online — especially as brick-and-mortar retailers sell out or limit supply — may get duped into buying a fake or unauthorized test kit.

Demand for test kits may increase after the Biden administration announced it will require health insurers to cover costs for home tests starting Saturday.

“Using these fake products isn’t just a waste of money; it increases your risk of unknowingly spreading Covid-19 or not getting the appropriate treatment,” according to a Federal Trade Commission alert published Jan. 4.

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New daily cases in the U.S. topped 1 million for the first time during the pandemic last week, according to Johns Hopkins University data, with swelling caseloads fueled by the highly contagious omicron and delta virus variants. Average new daily cases are more than five times higher than a month ago, according to Centers for Disease Control and Prevention data.

Rising infections coincide with an elevated incidence of fraud against consumers during the pandemic, with online shopping accounting for the largest share of scams reported to the FTC.

Here are the ways consumers can ensure they’re not buying an unauthorized, fraudulent test from online sellers, according to the FTC.

• Check the list: The Food and Drug Administration has issued an “emergency use authorization” to many companies for at-home tests. Consumers should consult the list of tests — antigen diagnostic tests and molecular diagnostic tests — approved for home use before buying. (Some deliver results at home, while others require consumers to ship their test sample for analysis.) The FDA also publishes a list of fraudulent Covid products, including tests.
• Do your research: Research a seller before you buy a test kit, especially if it’s from a site you don’t know. Search online for the company or seller plus words like “scam,” “complaint” or “review.” You can compare online reviews on retail or shopping comparison sites to a good sense of a company, product or service.
• Pay with a credit card: Consumers may be able to dispute a charge with the credit card company, if the charge is for an order that was never received or for a product that’s not as advertised.

Starting Saturday, private health insurers will be required to cover up to eight home Covid-19 tests per month for people on their plans. Americans can either buy home kits for free under their insurance plan or submit receipts for the tests for reimbursement from insurers. (Reimbursement doesn’t apply to tests purchased before Jan. 15.)