Figure 1: Sources and transmission of Campylobacter jejuni. Chicken is a natural reservoir of the C. jejuni where it colonizes in the mucosal layer of the gastrointestinal tract and can transfer between chickens through the faecal-oral route. C. jejuni can contaminate water and probably form an association with protozoans. Humans who encounter contaminated water, consume undercooked poultry, and unpasteurized milk get infected. The bacterium resides in the epithelial layer of the human gastrointestinal route and causes mainly inflammation and diarrhea. Sometimes antibodies produced against the bacterium mimic with the host nerve gangliosides resulting in demyelination and axonal degeneration of peripheral nerves that causes Guillain-Barré syndrome.