Where are you located
@fatimastic ?
I am in the tropics where we commonly get dry or wet pox.
I immediately separate my infected chicken(s) from the rest of flock in a quarantine cage. If she is the only one, I give her a buddy. I don't want the chicken to stress. I then clean and bleach all waterers and feed dishes and clean up my coops (with vinegar mix), change bedding, turn dirt in run etc. I also put my whole flock on vitamins like nutri-drench and/or B12 in water and only healthy snacks. This can be a serious deal and you want to squash it asap. I have horses so I use their Ecovet fly spray on the roosts and legs of my chickens to keep mosquitos at bay BUT, I have open coops. If you use a spray be careful of intense smell and chemicals in a closed coop.
Pox is spread via mosquito and or scabs. You can purchase a vaccine at feed stores, not sure of your area... ours is $27. and has 1,000 doses. Your virus is out and about already so your best bet is to get control of any potential spread. I can't stress vitamins and quarantine enough and mosquito control. Check your area for standing water and empty out obvious breeding grounds.
Ointment does not hurt, but that is a dry bump so I would not use ointment unless it gets wet or scab rips off. You want bump to heal and scab to fall of naturally, but don't want another chicken to peck at or eat... that is a way it can spread. The pox can last a few weeks but once it has passed the infected chickens will be immune. I have watched the pox wipe out the entire flock of wild chickens next door, the young are especially vulnerable, pox can blind, go down their throats... I have had minimal effect because of good husbandry and healthy chickens IMHO. To date, I have had 5 infected but all have survived with a few days sick and mild scarring that has mostly healed.
Good luck. Don't panic but do be proactive! Aloha!!!