Ringworm outbreak in feral colony

I noticed that several of the ferals we care for seem to have ringworm, I guess it is rgwrm, perfectly round bald patches with a red center. When I saw the first there was no red center so I thought "fur off for some reason/fight/accident" but then others showed same lesions and as of today one of my housecats has a bald spot w/red center.
I can always treat my housecats but how do I medicate ferals I can't hardly get close to?
I read there is a preventative vaccine for ringworm? Never heard of it before. Not for the infected ones of course but we still have to catch a couple of strays at the colony and another that just had a litter yesterday.
Should I include ringworm in vacc protocol.
And if you have any idea what to do for an unmanageable feral (only know of dipping..I used to put antibiotics in the food dishes but they obviously hate it) to treat them I'd appreciate any suggestions.
Thank-you!!

I don't know much/anything about ringworm, so I'm not aware of the medications. Trapping, if you are up to it, seems to be the best. Bring a cat to the vet, get the vet to agree it is ringworm, and give you meds. If you think a pill in their food won't work, ask your vet about alternatives for ferals. Talk to a vet before you do anything. If you decide to go the route of trapping, it's a big task, but definitely good for your ferals.

The meds you can get easy but with ferals it will be a hard task to cure.

Thank-you..I heard from a rescuer that said to mix Program with baby food, she's done that with her ferals, though it can be an ongoing thing like w/ other bugs.
I'll try it though and see if it helps. And yes, I think that trapping and letting the vet work with them should be easier..thanxs again