As far as I can tell, the answer is quite simple: there was no WHO test at the beginning. The CDC's test was developed and rolled out pretty much in parallel wi

As far as I can tell, the answer is quite simple: there was no WHO test at the beginning. The CDC's test was developed and rolled out pretty much in parallel with the German one the WHO has been using. They deployed it to state testing labs at pretty much exactly the same time as WHO Europe was rolling theirs out to one lab per European state. They also had a very aggressive plan to start testing flu surveillance samples in mid-February, much sooner than other countries. I'm not convinced they could pull off such an aggressive rollout without manufacturing their own tests.