What are your chicken's symptoms? Vent gleet is an infection of the digestive tract, and may be fungal or bacterial. Sometimes people mistake a red vent and diarrhea for vent gleet. It usually causes a red vent with white or yellow patches, smells bad, and the chicken has a continuous dripping of poop. Probiotics or plain yogurt, clean water with a little ACV, and antifungal medicines can help. If not treated it can spread in the flock, and most likely the chicken would be malnourished and could die. Do you have any pictures of the vent?