That's interesting, I know the use of chlorine dioxide gas made out of sodium chlorite + acid as a healing agent also called MMS, which works against bacteria, fungus and also viruses. I already used it on ponies to desinfect (rarely, but I sometimes feel the need), it's btw also a great way of desinfecting a fridge. It is used by mixing a few drops of sodium chlorite with salt acid, tartaric acid or such in a small pot, and when the gas begins to evaporate, put a large bowl over both the item which one wants to desinfect and the pot with the mixture. In case of a fridge, the pot with the mixture is put into the empty fridge and then the door is closed for a few hours.
Good thing about chlorine dioxide is, once it has finished working, it breaks down into water and salt and is therefore completely non-toxic. Nonetheless, the gas should not be inhaled deeply into the lungs, I can second other users here on that. For healing purposes, it usually is taken in water and only a few drops at once, with just enough acid for the activation process. The softest way of intake it to let the gas migrate into water which turns the water into CDS (Chlorine Dioxide Solution) without any excess acid at all. Just shouldn't be overdosed because it will oxidate toxins inside the body which the body will then work to get out, which again may trigger detox symptoms such as diarhhea, nausea etc. if too much is released at once. That part has nothing to do with ponies of course, but I find these things good to know, for cases of virus epidemics and the like.