I've never seen it but if it is spreading it is contagious.
There's no way to know how to treat it whether chemically or homeopathically if you don't know what it is.
Your country should have a poultry lab you could send one to for lab work so you know what you're dealing with.
Antibiotics work on a very small percentage of things that afflict chickens.
It could be fowl pox which is a virus that has to run it's course over 2-3 weeks. The other suggestion is it could be ant bites. If it is pox and there are those lesions around the eyes, there is a real chance of blindness from secondary bacterial infections. Do you have any antibiotic drops or ointment for the eyes? These things tend to be very hard on chicks.