I can't really give this a favorable rating due it being called strategy and it's based in pure luck. Peru or Madagascar are luck. You infect them or lose. No country or anywhere large enough to be on a map except for the polar sides of the planet and maybe even them don't have only ONE method to get into them.
So I have disease which claims it's totally invisible there is no nothing on my visibility bar, it has no symptoms it does nothing...Magically gets caught and whoops there goes Peru closing a border. GG you lost. I'm not seeing any point to this in honesty.
Also seems unless you magically mutate a vaccine will auto stop infections even if you add more things to it which then doesn't make sense and becomes luck...There may be some hidden under laying play points that you have to follow but that doesn't make it worth playing then it's basically saying do X,Y,Z in this order or lose.
Good for a few moments of experimentation, but doesn't hold up overall. 2/5