It's hard to tell but it could be. We have had good luck treating zoa pox with hyrdogen peroxide rather than an antibiotic. They're dipped for so little time in antiobiotics that I don't see much of an improvement for it. Here's what we do:
Put the zoas in a cup of tank water. Add a cap full of hydrogen peroxide and stir. Continue doing this till you start seeing bubbles coming off the polyps. Leave em in there for 30 minutes.
We have used this for fungus, zoa pox, etc. and brought many very sick zoas back from the brink. We have accidentally left zoas in the solution for 1.5 hrs before without devastating results.