zoonoses and communicable diseases common to ... - PAHO/WHO

CAMPYLOBACTERIOSIS 75Figure 9. Campylobacteriosis (Campylobacter fetus). Probable mode of transmission.1. Campylobacter fetus subsp. venerealisBullSexual contactCow2. Campylobacter fetus subsp. fetus (intestinalis)SheepPlacenta,fetuses, excretaEnvironmentalcontamination(pasture, water,objects)Oral routeSheepDirect contact?Contamination of food?ManPlacental route?ManNOTE: It is not known how the disease is transmitted to humans; transmission is assumed to occur through direct contact,contamination of foods, or transplacental passage.aborted fetuses and vaginal discharges, contain a large number of Campylobacter. Afew infected ewes become carriers by harboring the infection in the gallbladder andshedding the agent in fecal matter. Contaminated grass, tools, and clothing are thevehicles of infection. Transmission is oral. Sexual transmission has not been demonstrated,but knowledge on this subject is inadequate.Role of Animals in the Epidemiology of the Disease: Animals are the naturalreservoir of C. fetus. The agent has been observed to lodge in the human gallbladder,but it is not known how often man may become a carrier and give rise to humanfoci of infection. It is probably an exceptional occurrence. The mechanism of transmissionfrom animals to humans is unclear.Diagnosis: So far, diagnosis of campylobacteriosis in man has been largely fortuitous,when C. fetus is discovered in hemocultures of patients in whom the etiologywas not suspected. During the febrile period, repeated blood samples should betaken for culture. In cases of meningitis, cultures of cerebrospinal fluid should also