"eye irritation" is not normally associated with EC. But- sometimes , because the rabbit is blind in the eye affected by EC it can bump into things and cause irritation. -- If the eye appears irritated, I would suggest some broad spectrum antibiotic eye meds,[meds effective against pinkeye as well as bacterial infections] and a very close look at the eye and under the lids, to see if it has been scratched or has some debris under the lid... in a young rabbit, EC eye will "usually" appear opaque and the pupil will "usually" be unresponsive to light stimulation.
-----------Have you had any other EC symptoms in your rabbits? [circling , listing,head tilt, front or rear end mobility or weakness issues.] if you have had and bred your rabbits for a while and not brought in new stock lately, or exposed your rabbits to the urine, or feces of outside rabbits -- it would be less likely to suspect EC...
[ but the disclaimer is--- most rabbits tested for EC titer had been exposed to EC-- so it is a very common, and widespread disease... that can exist in a rabbit herd without showing any symptoms for a long time- some rabbits will live a normal healthy life and never exhibit any symptoms-- often, it is just pet rabbits that show symptoms because they are kept well beyond their healthy and productive years, ]