Better form a new org that is apolitical and concerns itself with promulgating health and disease prevention rather than some political agenda?
It is not a police, it has no coercive power. The reason is obvious if you think more than 10 seconds about how to get sovereign governments to cooperate on public health matters.
What would be your ideal organisation? One subservient to the American government? Or do you want it to be a world government above sovereign states? How do you think it would fly?