Declaring an emergency is a dirty work, but someone has to do it. When facing a serious threat to global public health, even if complete evidence is lacking, someone has to take the responsibility to push the red button that activates a chain of coordinated actions (such as cooperation among states and research of vaccines). Choosing to do this, the risk of giving a false alarm is unavoidable. On the other side, one could decide to wait until something more is known, with the awareness that, in this way, it is possible to act when it is too late.