This is a graphical resurrection of sorts. An old image of mine I made back in 2013/14 and some text from what used to be the H7N9 page on my original blog  from back in 2014.
Knowledge of H7N9’s evolution has likley advanced since then, but I’m going to put this up for now and get to work improving on it in the coming days.References…
- Gao et al. Human Infection with a Novel Avian-Origin Influenza A (H7N9) Virus; New England Journal of Medicine (2013)
- Liu et al. Origin and diversity of novel avian influenza A H7N9 viruses causing human infection: phylogenetic, structural, and coalescent analyses. The Lancet (2013).
- Lam et al. The genesis and source of the H7N9 influenza viruses causing human infections in China. Nature. 2013