Immediate AZT Use May Avert Some AIDS Cases

Evidence from a new study suggests that immediate treatment with the drug AZT can prevent the development of AIDS in health care workers stuck by needles or other instruments contaminated by the virus.

The U.S. Public Health Service and the International AIDS Society has already used the research as the basis for recommendations that such drugs be immediately given to those with an occupational exposure to the human immunodeficiency virus that causes AIDS.

The risk of contracting HIV can be cut by up to 80% if the immediate treatment with AZT is given, researchers said in the study published in today’s New England Journal of Medicine.

British-based Glaxo Wellcome Plc makes AZT.

The results do not definitively prove that immediate AZT treatment cuts the risk of AIDS. But now the evidence “is far more convincing,” said Dr. David Henderson of the National Institutes of Health Clinical Center in Bethesda.

A team led by Dr. Denise M. Cardo of the Centers for Disease Control and Prevention in Atlanta based their 80% estimate on the cases of 33 health care workers who contracted the AIDS virus and 665 who did not after they were exposed to contaminated blood on the job.

The 698 people were from the United States, Italy, France and the United Kingdom.

The Cardo team found the risk of developing HIV was higher if the cut was deeper or blood was visible on the instrument that caused the cut.

The immediate treatment was not successful in all cases.

“At least 13 instances of failure of post-exposure prophylaxes with [AZT] in health care workers have been documented worldwide, indicating that any protection provided is not absolute,” Cardo and her colleagues said.