not-yet-known not-yet-known not-yet-known unknown 1. INTRODUCTION APEC is a harmful strain of bacteria that causes infections in poultry like chickens, turkeys, and ducks. These infections can affect different parts of the body, leading to conditions such as liver inflammation, lung infections, heart problems, reproductive system infections, and joint or bone infections. This group of diseases is often called avian colibacillosis.1,2 Studies show that E. coli enters the bloodstream through the lungs and air sacs, with its ability to avoid being killed by immune cells helping it cause disease. Key factors in its harmfulness include proteins that help it stick to surfaces (adhesins), a system for trapping iron (aerobactin iron-sequestering system), a protective K1 capsule, temperature-sensitive hemagglutinin and resistance to the immune system.2 Yolk sac infection and colibacillosis are major causes of early chick deaths, with APEC being the most common pathogen responsible.3 Certain APEC strains, like ST9, ST131, O1, O2, and O18, have similar genetic traits to E. coli that cause urinary infections and meningitis in humans, making them capable of affecting human health.2 Here we presented a review to control, prevent and mitigate infections caused by APEC especially in chicken.