I agree with all the tips. We will be there Jan 3 to 9. My son has the flu now. If you get flu like symptoms, go to the dr immediately. If you have the flu (they can do a nasal swab test that is very accurate and fast), the dr can put you on an antivirul medication that lessens the severity and duration of the flu. It has been great for my DS. The dr also gave us prescriptions for our DDs since they may end up with it too.
But I must add, in defense of some of the parents at WDW whose kids seem sick, that many times, well after a person is not contagious, they continue to have a cough. I myself and my kids have had coughs for 3 to 6 weeks after an illness. The kids' dr says 6 weeks is completely normal for a cough to linger. Also, the drs and schools do not consider someone to have a fever until it hits over 100 deg. (I think if my kids have a temp of 99 or above they are coming down with something, but the school did not send my DD6 home a few weeks ago when her temp was 100 deg, but not above AND she wanted to stay.) Also about runny noses...kids have them all the time. If you stayed home everytime your otherwise healthy child had a runny nose, you'd never go anywhere from at least Oct to March and they'd never go to school. I go by how the kid feels and how they are acting. Laying around and only watching tv, they are SICK!!
Don't misunderstand and think I'm advocating taking sick kids anywhere. We at this very moment are skipping our normal Christmas Eve family festivities because DS is sick. I'm also one to use a paper towel to open bathroom doors when I leave, etc. And I'm definitely bringing hand gel and Lysol on this trip.
Merry Christmas to all!! And good health to the OP's sweet daughters.