After four years of research, scientists from the Department of Agriculture have found that a virus similar in genetic structure to the AIDS virus is more common in cattle in United States than researchers had anticipated. The scientists say there is no evidence that the virus can infect people. The virus, bovine immunodeficiency-like virus or BIV, is spread through the blood and is a member of a family of slow-acting viruses that have been shown to reduce the activity of an animal's immune system.
Such immune suppression, veterinarians said Friday, can open the way for other infections. The virus, which was first isolated in 1969, has been shown to cause illness in calves, a top scientist at the Department of Agriculture said Friday. Scientists say they believe that the virus causes immune suppression in adult cattle, but how powerful it is remains uncertain.
Researchers said much more needs to be found out about the virus to understand its importance to the $55-billion cattle and dairy industries.
"We will continue to do research on this virus because it will help create a body of information that may provide a way to reduce the costs of production," said Dr. Harry Mussman, the deputy assistant secretary of agriculture for science and education.
"It is very important that the public understands that this is not the AIDS virus. We do not have the AIDS virus in cattle."
Dairy and cattle producers now lose hundreds of millions of dollars each year because sick animals must be culled from their herds. In addition, cattle and dairy farmers spend $300-million to $500-million for drugs to treat sick animals.
The Food and Drug Administration has sought in the last two years to crack down on the use of such drugs because some are known carcinogens and residues have been found in meat and milk, posing a threat to public health.
The bovine immunodeficiency-like virus was first isolated in 1969 by Dr. Martin Van Der Maaten, a veterinarian at the Agriculture Department's National Animal Disease Center in Ames, Iowa.
The virus did not receive intense scientific scrutiny until the mid-1980's, when molecular virologist Matthew Gonda began to study BIV and determined that its genetic structure was similar to the human AIDS virus. Both viruses have eight genes, Gonda said Friday, and magnified, they look remarkably alike.
The Foundation on Economic Trends Friday filed a formal petition with the Department of Agriculture asking the government to take immediate steps to quarantine cows infected with BIV, and accelerate the pace of research.