WASHINGTON -- A report released yesterday cast doubt on whether a Florida dentist -- accused in a highly publicized case of infecting five patients with the AIDS virus -- actually was responsible for the transmission.
But the report, published in the weekly British journal Nature, fell far short of proving that the dentist, Dr. David Acer, who has since died of acquired immune deficiency syndrome, was not the source of the infection.
"We are not saying that the dentist did not infect the patients -- we're saying you really can't prove it one way or the other," said Ronald W. DeBry, an evolutionary biologist in Florida State University's department of biological science.
"We are not saying that we can prove any other source of infection for any of the patients," he added. "What we are saying is that you also cannot prove the dentist was the source."
The case has been cited as the only example of transmission from an infected health professional to a patient since the AIDS epidemic began in 1981.
But there have been several dozen instances in which health care workers have become infected through contact with the blood of an infected patient.
Officials from the U.S. Centers for Disease Control and Prevention, who conducted the initial investigation and have concluded that Dr. Acer was the source, dismissed the Nature report, saying that it ignores substantial additional evidence that points to him.
The investigation, among other things, pointed out that none of the five infected patients had any known high-risk behaviors that would have made them vulnerable to transmission.
"They are ignoring everything else in the investigation," said Dr. Harold Jaffe, the CDC epidemiologist who was in charge of the investigation.