But they are _likely_ to run a fever if they are symptomatic. And between 100% "non-accuracy" of not measuring temperature at all, and some much higher level of accuracy of a non-contact IR thermometer, I pick the latter. I have one BTW, it seems pretty accurate to me (confirmed with a calibrated thermopair, unless you're trying to measure something reflective or transparent).

Cheap general purpose IR thermomenters from Melexis claim greater than +-0.1C accuracy in the common "body temperature" range: https://www.mouser.com/new/melexis/melexis-MLX90615-infrared...