[empath75]

They are supposed to only test people with flu like symptoms that test negative for flu. Which this person did.

[LolWolf]

Still, the test specificity (or more generally, its predictive power) is likely to be quite low simply due to the sheer number of flu cases.

Otoh, this doesn’t really explain why there would be regulations against developing in-lab tests (as another of the sibling comments mentions).

[prostheticvamp]

Shit-tons of people with the flu test negative for flu. It’s not a very sensitive test.