|KNOWLES, JR.,, D.|
Submitted to: Journal of the American Medical Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/9/2000
Publication Date: 11/1/2000
Interpretive Summary: Cattle can be infected with a wide variety of viruses, but not all the viruses will cause disease. Cattle in this country and in other countries are often infected with a virus called the bovine lentivirus or the bovine immunodeficiency-like virus (BIV). Although cattle are often infected with this virus, it is not currently known if this virus causes disease. Many experimental studies of the virus have shown that the virus causes a life long infection of cattle. However, with other viruses from the same family, for example the human immunodeficiency virus (HIV), the type of disease that it causes often occurs many years after the original infection and the disease progression is often related to the lifestyle of the patient. In experimental infections of cattle, the cattle are not often kept for many years because of the expense, and therefore any disease caused by the virus may be missed. Very few studies of naturally infected cattle have been undertaken, and it remains unknown what the disease potential of BIV may be. The manuscript recommends that additional studies of naturally infected cattle be undertaken to determine if BIV is a serious disease agent in cattle.
Technical Abstract: The bovine lentivirus, also known as the bovine immunodeficiency-like virus or BIV, was first isolated from cattle in 1969 from a chronically sick dairy cow. This virus has since been shown by different serologic tests to be widely distributed in cattle in the United States and around the world. BIV causes a chronic infection of cattle that is assumed to be life-long like many other retroviral infections. However, it is still not conclusively known if the virus is associated with disease. The lentivirus group of virus are not commonly associated with cancer, and generally cause disease that fits into two groups, an immunodeficiency causing group or an auto-immune mediated type disease. It is unclear if BIV falls into either group. Experimental inoculations with BIV has not documented any immunological changes that would be consistent with immunodeficiency, nor has any evidence of consistent acute or chronic disease been reported. Some anecdotal field observations suggest it may be associated with a number of different chronic disease disorders in cattle. However, few epidemiologic studies have been conducted to conclusively prove an association with any disease condition. The true role of BIV in cattle disease needs to be further investigated before any definitive conclusions can be made.