I’m currently laid up with the flu, feeling sorry for myself, watching trash on TV and periodically shoving cat butts out of my face.
The reason for this, of course, is that new strains of influenza virus appear all the time. Like it or not, that’s evolution.
On the plus side, I’m glad that my ancestors had to deal with a lot of the same problems, and thus developed a robust immune system that can fight off new types of attacks, including (and this is part of what’s making my life miserable at the moment) raising my body temperature so that hopefully some of the chemical processes that viruses depend on to multiply won’t happen as quickly, and thus slow down their reproduction, to give the rest of the immune system a chance to catch up.
(Another reason why I’m sick, interestingly enough, is that I live in a country that has lots of direct commerce with China.)