I am gonna go the Walt Disney way, frozen... (his head has been cryptogenetically frozen and rumors say, they titled the movie Frozen (originally the Snow Queen) so in google searches it wouldn't be Walt's head coming up)
The stuff you are talking about are man made. We bring those diseases on ourselves and they are not written in the natural code. For example, you will find more Americans suffer from heart disease and diabetes than Italians or Greeks and that because of their diet not because there is anything different in their genes.
Small minds think small! Controlling the spread of the poliovirus around the world is not going to stop our Sun from running out of fuel.
It will enhance it in fact, when the mad scientist who was saved from the poliovirus because he/she was vaccinated figures out a way to make a "Starkiller".
Humans have to survive all the global catastrophic risks they face on earth before they can leap to the next planetary system and I hate to tell you that the chances of that happening is big zero! Specially when we have leaders today who intend to build more nuclear weapons and reverse the laws that protects the environment. good luck