It makes sense for at risk people to be tested for a COVID. They can get an infusion of antibodies that appears to help tremendously.
Re antibodies: The ones that work for Delta and earlier strains, don’t work for Omicron, according to a nearby FR article.
But, even if you have Delta, you have to get the antibodies within a few days of initial symptoms. So, if you’re at risk, and don’t know whether you have delta, which gets bad over a course of 2 to 3 weeks, or Omicron, which appears to be more like a cold, it’s understandable that you’d be jumpy if you’re in the high risk group. Given all the existing publicity, of course.