Present Evidence for the Association Between Bovine Lymphosarcoma and Human Leukemia.
Proceedings of the VII International Congress of Rural Medicine, Salt Lake City, Utah, September 17-21, 1978, International Association of Agricultural Medicine 1978 Sep:122-126
Evidence for an association between bovine lymphosarcoma and human leukemia was reviewed. Epidemiological studies of leukemia and lymphoma in rural and agricultural populations were summarized. These have shown that rural populations and farm workers have an elevated risk for developing lymphatic cancer. The role of bovine leukemia virus (BLV) in the occurrence of leukemia and lymphoma in agricultural areas was discussed. BLV is known to be present in cattle herds and to cause lymphosarcoma in dairy and beef cattle. BLV has been shown to be present also in milk from infected cows. It was noted that although pasteurizing milk will kill BLV, human exposures can occur by drinking unpasteurized milk. Surveys have shown that around 76 percent of all dairy farmers and their families drink unpasteurized milk. Human exposure to BLV can also occur by consuming other unpasteurized dairy products such as cheese or cream. BLV is known to be transmitted by direct contact and possibly by insects among cattle. BLV can also infect a variety of cell cultures as well as other animals such as sheep, goats, and chimpanzees. The lack of host specificity is considered to increase the possibility that humans can be infected by BLV, although serological studies in leukemia patients, dairy farmers, and BLV laboratory workers have produced inconclusive results. A study conducted in rural areas of Iowa has found that the presence of BLV in cattle, as indicated by cases of bovine lymphosarcoma, increases the risk of acute lymphatic leukemia in male farmers. The authors conclude that there is sufficient evidence to indicate that BLV may be involved in the etiology of human leukemia, especially acute lymphatic leukemia in adult rural males.
NIOSH-Grant; Grants-other; Livestock; Blood-disorders; Epidemiology; Leukemogenesis; Viral-infections; Lymphatic-cancer; Agricultural-workers; Dairy-products; Risk-factors;
Prev Med & Environmental Hlth University of Iowa Inst/agric Med & Environ Hlth Iowa Oakdale, Iowa 52319
Other Occupational Concerns; Grants-other;
Proceedings of the VII International Congress of Rural Medicine, Salt Lake City, Utah, September 17-21, 1978, International Association of Agricultural Medicine
University of Iowa, Iowa City, Iowa