Huffington Post:

Confused By The CDC's New COVID Isolation Rules? Here's A Clear Guide.

What's the Benefit of a Fourth COVID Vaccine? Experts say additional boosters could provide diminishing returns Amanda D'Ambrosio medpagetoday

...  as daily infections break records and hospitals across the country near capacity during the Omicron surge, many people have raised questions about whether they'll need to get a fourth dose.

Backround on why  rapid tests for COVID-19 are in such short supply

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At-home rapid antigen tests are reselling for triple the retail price on some digital marketplaces. Testing locations in L.A. County have been overwhelmed by mile-long lines, with some events canceled due to traffic. Some would-be self-testers have resigned themselves to driving between CVS and Walgreens locations, hoping to snag a kit at a reasonable price.

Companies are racing to fulfill the excess demand.

Abbott Laboratories, which makes the BinaxNOW rapid antigen test, expects to produce 70 million tests this month and is working to raise that to 100 million, said CEO Robert Ford.