People with Campylobacter infection usually have diarrhea (often bloody), fever, and abdominal cramps. The diarrhea may be accompanied by nausea and vomiting. These symptoms usually start within 2 to 5 days after exposure and last about a week. Some infected people do not have any symptoms.
In people with weakened immune systems, such as people with the blood disorders thalassemia and hypogammaglobulinemia, AIDS, or people receiving chemotherapy, Campylobacter occasionally spreads to the bloodstream and causes a life-threatening infection.