Infection and vaccination both leave their mark in your blood.
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by Matt Hitchings, University of Florida and Derek Cummings, University of...
The key to rapid antigen testing is to test early in the course of COVID-19 infection, ideally several times 24 hours apart.
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Understanding how much protection a vaccine offers is not as simple as it sounds. Andriy Onufriyenko/Moment via Getty Images
An epidemiologist answers 6 questions
by Melissa Hawkins,...