IIRC it established two separate levels of the disease that’s basically the same as the later ghoul/feral ghoul divide in Fallout. So there were vampire zombies that hunted people - including each other - and ones that had managed to stabilize the condition with medical treatment. He hunted them indiscriminately, and it was the latter group that managed to take him out with an organized military strike on his fortified compound.
IIRC it established two separate levels of the disease that’s basically the same as the later ghoul/feral ghoul divide in Fallout. So there were vampire zombies that hunted people - including each other - and ones that had managed to stabilize the condition with medical treatment. He hunted them indiscriminately, and it was the latter group that managed to take him out with an organized military strike on his fortified compound.