numbers of abortions in the herd. In naïve herds, the incidence of abortions can reach 70%. Abortions occur within 3 to 4 weeks of infection. Infected ewes rarely show systemic disease, but may include diarrhea, fever, and vaginal discharge. If infection occurs near-term, weak lambs are born and often die within several days. In rare cases, a fetus may die in utero and cause an ascending infection from the placenta, septicemia and possibly death in the ewe. Ewes can often mount sufficient immune responses following infection, therefore subsequent lambing seasons are not as severely affected. Campylobacter jejuni, another gastrointestinal tract commensal of ruminants, is another important cause of abortion in ewes. Zoonosis/interspecies transmission Campylobacter fetus subspecies fetus infections are associated with gastroenteritis and, rarely, sepsis in people. Although most infections are self-resolving of particular concern are those individuals with underlying conditions (e.g., HIV), seniors, as well as pregnant women. Clinically relevant transmission between humans generally involve neonates. Zoonotic transmission of Cff occurs mainly by ingestion of food and water contaminated by feces from infected ruminants, or ingestion of unpasteurized dairy products from infected cows. Ingestion of raw ovine or bovine liver has also been linked to sources of infection. Likewise, cross-contamination due to improper food safety has resulted in similar infections. Symptoms of acute gastroenteritis associated with Cff infections include abdominal cramping, nausea, diarrhea and fever. When sepsis does occur, Cff can cause a myriad of infections in accidental hosts such as perinatal, neurological and endocardial infections. Occasionally, abortion in humans can occur, similar to that in sheep, as a result of placental infection through septic spread of Cff from the gastrointestinal tract. The fetus can either undergo spontaneous abortion or be born with an ongoing infection which can eventuate in the infiltration of nervous tissues. Campylobacter fetus subspecies venerealis rarely causes sepsis in immunocompromised individuals. Diagnosis Epidemiological clues in the breeding herd or flock can indicate Campylobacter fetus infections. Often, C. fetus may not be suspected until herd level changes are noticed, generally at the end of the breeding season (Cfv) or end of herd gestation (Cff) (e.g., high incidence of open cows, multiple returns to service, high incidence of abortions in ewes). If suspected, C. fetus can be diagnosed through basic culturing and laboratory tests such as polymerase chain reaction (PCR) assays, enzyme linked immune sorbent assays (ELISA), and vaginal mucus agglutination test (VMAT). Diagnosis depends on isolation