It's a risk leaving it unpaused, certainly, and only you can really decide whether it's worth taking. Personally I'd train up a villager to at least Trainee Doctor just in case. However, you might find that your villagers are perfectly healthy when you get back, and feel that you've lost the chance to gain more tech points/food. Of course, you might find them all, or nearly all, dead or severely weakened by sickness.

Your choice!