Thanks for your question. For many people, doctors included, the choice of which form of immunization to obtain or offer is a personal one. However, I will try to provide you with the facts you may need to make this important decision.
The short answer is that both forms of the vaccine appear to have equivalent efficacy, so the choice depends upon a number of other factors.
As I mentioned, flu mist contains a living virus that has been treated so that it can reproduce in the nasal passages, but not to the extent of being able to cause significant disease. It hangs around just long enough to induce the immune response, and may cause some rhinorrhea (runny nose) in addition to the usual symptoms after immunization of low grade fever and muscle aches. There is obviously no area of redness or soreness as you often get with the shot. Safety is the same for both, and I can assure you that there is no mercury in the nasal spray.
Flu mist, however, cannot be given to children less than 2 years of age, or children under 5 who have had wheezing in the past year. It is also not recommended for anyone with an immune defect, or anyone who lives with someone with a SIGNIFICANT immune deficiency. This is all for the theoretical chance of transmitting the virus contained in the vaccine to the immune compromised individual. However, to my knowledge that has never actually happened. Many children less than the age of 9 will require two doses of vaccine (regardless of which form they receive) to be completely protected, so if the school is going to administer the flu mist, you need to be certain they will provide a second dose for those who need it. If in doubt as to how many doses your daughter needs, check with her pediatrician. I put the link to the algorithm in my original post, but here it is again, if you need to refer to it.
I would like to hear what you decide to do