How old is she? Can you get a clearer picture? Do you see any bubbles/foam in the eye, drainage from nostrils, sneezing, or lethargy? Have you got mosquitoes about right now who could be spredding fowl pox? If you cannot see her eye, use a warm wet compress held to the eye for a few minutes to soften the crust, and open the eye to look for anything in it. I would use some Terramycin eye ointment or plain Neosporin in it 2-3 times a day. Rinse it with saline or eye wash if there is gunk in the eye.