This sounds science-y.

In fact, I use NeilMed, a commercial saline & bicarb powder together with distilled water, and I know from past exchanges on HN that lots of others here do, too. My own doctor said it was fine and lots of her patients do it. The solution runs out the other nostril, which is gross so you do it in private.

I have very few colds, allergies, or sinus infections since starting it, although it doesn't eliminate them all.

This Fort Detrick guy, though... that might be misinformation. I use the spray once a day, twice if I have a cold. Definitely not constantly.