For those interested in self- or caregiver-administration, the vaccine manufacturer plans to make the vaccine available through a third-party online pharmacy. Those who choose this option will complete a screening and eligibility assessment when they order FluMist. The third-party pharmacy determines eligibility based on the completed screening and, if it is determined that the intended vaccine recipient is eligible, the pharmacy writes the prescription and ships the vaccine to the address provided by the individual who placed the order.

If it is sold over the counter a lot of people won't be able to afford it because insurance won't cover it.

It's a weakened live virus, so I assume there is some risk of it becoming contagious. Fortunately it's the flu and not polio. And I assume it's also for the same reason as antibiotics; you don't want people overusing it and making new, resistant flu strains.