My daughter's endo said that there was no need for her to get a flu shot since CAH does not pose any pulmonary problems. Last year I decided to get it done anyway to prevent any visits to the hospital if I could, and she just received her shot for this year. I must admit that I did not notice any difference in the amount of times she got sick last year. The flu shot only works against one certain type of the flu, so against that one (usually later in the winter)it works wonderfully but all others will still be contracted if your child comes into contact with the virus. That said, I still feel more comfortable getting the shot for her. It only hurts for a second and she's very used to being "poked and prodded". If it can take away even one visit to the hospital, I believe it's worth it. Best of luck to you.