SandraHi Sue,
I don't know much about dose tunings but I can tell you that I think the illness thing is not related to the cortef doseage. Of course I could be wrong but from my experience I have to tell you that my 3 yr old (non CAH) has been sick with something since starting his mothers day out program. He goes to a little daycare 3 times a week for 5 hours. As soon as he started going he caught everything under the sun. At one point I was in tears because I was so frustrated that he was always sick. He is almost 4 now and has done a complete 360. He still gets sick but not so much.
My husband also had to remind me that my now 7 yr old also (non cah) was also a walking germ at that age as well. I used to get a, what seemed, daily call from his daycare say that he was sick again!
Both of my non CAH guys had tons of ear infections, throat stuff, bronchitis, pnuemonia, colds, ear/ mouth/foot virus, sinus infections, allergies, high fevers, split lips, broken bones. You name it they probably had it.
I cried when I found out that I would have to watch my little one so carefully when sick because I just kept getting flash backs of my other two and how often they got sick. :)
Now, my older two boys are very healthy and just get the usual sickness here and there. I really think that being in a day care helps her catch all these lovely bugs!!
All I could suggest is that you wash hands all the time. Chris D suggested that to me and I have become Mrs. Handwasher. I don't use the antibacterial stuff. I don't want to create a super germ. I just use plain old soap and water.
The first thing my boys do when they get home from school take off their shoes and wash their hands. I used paper napkins in the downstairs bath they use to keep germs from going from one to the other. I really think this has helped. I also always wash the babies hands and I ask people not to touch his hands.
I know that this is a little overboard but I think it has helped tremendously. I even have my husband asking people to wash their hands before they pick up the baby.
Another piece of advice is that once your 3yr old has built up her immune system, the illnesses should slow down. I remember what my 7 yr old's ped told when my second son was born. He said that he would expect to see us about once a month. I couldn't believe it but it was true. He also said that by the time my child was in 1st grade he wouldn't be getting sick as often. That is true too!
So, try those suggestions and see how they work for you. Oh, if you 3 yr old is like mine and loves to put tons of soap on his hands so he has to rinse FOREVER!, buy one of those dial foam pump soaps. Then when it is empty fill it with just a little bit of regular hand liquid soap and the rest with water and it comes out foamy. The kids get just enough soap and it is easier to rinse off.
Sandra