[She frowns. She knows Zero is, at least today, trying to be tactful about everything. Still... she feels a bit uncomfortable with it.]
Vampirism isn't an allergy or a disease. It's a state of being. People need food, water, and shelter in order to survive. Vampires just... have an extra ingredient added to the mix. [Now that was down playing it a little, but it's the truth, too.]
We have not only tablets but packets of blood in order to cater to that need. There isn't a list for people with peanut allergies or anything different. There's only a risk if the individual vampire already poses a threat to the dome as a whole. When food shipments and supplies stopped coming, none of the vampires threatened or acted out against the humans or each other. That's because I have no more desire than Yuuri, or any of my other friends in the dome to hurt someone for my own benefit.