Don't forget that Carol has asked Rick to kill Pete. Pete who happens to be the Dr who might be able to save Tara. Was Jessie's husband something useful in the comic? A bit annoying he can't just be killed and be no loss...
Now, this isn't confirmed, but...in a sneak peek for S05E15, Michonne asks Rosita is she okay, to which she replies that she is stable. Now, since Rosita is working as a medical asisstant for Pete, chances are large that she could mean Tara.
I doubt it. I'm positive she makes it to Season 6 especially since in one of the clips for the next episode Rosita said she is stable and iirc in the comics Scott was never really stable and was just constantly getting worse with his fever, but it has been a while since I've read that arc.
And remember Aiden and Nicholas got 4 people killed a little bit before Rick's group got there which explains the four graves.