@FinchTH @Algorithmus22 @alexmeshkin I suspect not following the directions fully is another reason. There are probably a lot of 2 second swabs when the instructions all say 15 seconds.
@FinchTH @Algorithmus22 @alexmeshkin 我怀疑没有完全遵循指示是另一个原因。当说明都说 15 秒时，可能有很多 2 秒的拭子。