Hemorrhagive Fever is something “they” were manipulating years ago to “see if it could be made to spread more”. I read about this years ago.
The thing is it requires close physical ie touching someone with the disease to catch it. It is not a respiratory virus unless they really messed with it. It is less catching than HepC.
I assume that any tinkering with Crimea Congo Hemorrhagic Fever to make it more contagious
would be to make it into an aerosol, airborne droplets.
So far, that isn't known to have happened .. yet (!).