Seroepidemiologic studies on the possible relationships of human and bovine leukemia: Brief communication

A seroepidemiologic study was conducted in an attempt to identify antibodies against the bovine leukemia virus (BLV) in people exposed to cattle with lymphosarcoma. Farm families, farm employees, and veterinarians in contact with cow herds having documented cases of lymphosarcoma were tested for precipitating antibodies to the BLV with the agar gel immunodiffusion test. The cattle also were tested serologically. Information was collected form the farm families regarding consumption of unpasteurized milk from their dairy herd. Twenty-one dairy herds with documented cases of lymphosarcoma were identified. A total of 846 cows from these herds wre bled, of which 33% were serologically positive. No positive sera were found in the 45 dairy farmers, family members, and farm employees associated with the herds with lymphosarcoma. Consumption of raw milk was reported by 77% of the farm group. In addition, 83 veterinarians, 30 leukemia patients, and 200 control human sera were tested and found negative for antibodies to the BLV.