The strange thing about a virus is that it can't self-replicate but needs to invade a living host cell to reproduce. They are effectively rogue strands of DNA but mutations can occur in the reproduction process. Do they even qualify as a true form of life? So I don't think they can battle each other for dominance.
I've only had real flu a couple of times in my life, anyone remember Hong Kong flu of the early 1970s. Real flu is a f***ing bastard and you have difficulty even reaching the bathroom from your bedroom. It certainly wont have gone away. The strains we are fighting today are derivatives of the 1918/19 flu which they think was also the source of an epidemic in the 1800s and possibly the Middle Ages as well.
They tend to monitor the flu strains in Australia before producing the vaccine for the winter here in the UK.
Viruses aren't usually considered living organisms, no.