This TV series is absolutely horrible because:
1. It's unrealistic in almost ever which way possible.
2. An unfathomable level of make believe is expected by the viewer.
3. The production is stingy and cheap.
4. It's depressing and total waste of time.
5. There is little to no plot, it's only to set up gore effects which are unrealistic and actually crudely photoshopped (not even CGI, WTF?).
If it had been realistic in some ways (especially the ill stricken humans), interesting plot with a professional production, it could be worth watching for entertainment purpose.
Decent actors, I'll give it that.