Campylobacter fetus is a species of Gram-negative bacteria.
In addition to causing some cases of spontaneous abortion in cattle and sheep, C. fetus is an opportunistic human pathogen and can cause bacteremia and thrombophlebitis. Though rare, C. fetus can lead to fatal sepsis in newborns and immunocompromised individuals. C. fetus, along with C. coli, has been shown to cause sepsis. Bacteremia can lead to localized infections of the meninges in the brain, the respiratory pleural spaces or lungs, joints, the pericardial sac around the heart, or the peritoneum.