This one was obviously influential on 68's NIGHT OF THE LIVING DEAD with it's hordes of undead roaming around after our sole survivor Vincent Price who's boarded-up inside his home during the night. Here, instead of flesh-eating zombies though, they are neck-biting vampires caused by a global airborne plague. This one gets extra credit for being the first version of the story that would go on to be filmed a few times as THE OMEGA MAN in '71, a big-budget CGI Hollywood piece of crap with Will Smith called I AM LEGEND(which was also the name of the original story) followed quickly by a shitty shot-on-video thing called I AM OMEGA(both in 2007). I would usually say stick with the original but the 70s version is the one I've honestly gone back to more often for a fun apocalyptic watch even if this one is in that semi-classic category..
There is a slightly longer ending if you're not watching the AIP TV-cut which seems to be the most common out there on all the cheap-o public domain DVD sets.
Complete cut with baby ending!: