Dentist With AIDS Is Suspected of Infecting Patient : Disease: If true, it would mark the first reported case in which a health-care worker has spread the virus to a patient. Experts stress that such a risk is minimal.

A dentist with AIDS may have spread the deadly virus to a patient during a tooth extraction, federal health officials reported Thursday. The finding, if true, marks the first reported instance in which a health-care worker has infected a patient.

The health officials cautioned that the possibility of another source of infection “cannot be entirely excluded.” But they said their investigation identified no other means by which the patient, a young woman, might have been exposed to the human immunodeficiency virus.

Health experts on Thursday emphasized that the risk of infection by a physician, nurse or other health worker remains minimal. But they said the report reinforces the need for policies to protect patients and perhaps even limit the use of certain procedures by infected workers.

“It’s an issue that can no longer be swept under the table,” said Dr. Neil Schram, a Los Angeles County internist who helped draw up the California Medical Assn.’s 8-month-old policy on the subject, said to be the most explicit adopted anywhere in the United States.

“But we have to come up with appropriate recommendations,” Schram cautioned. “We can’t let people get hysterical about this.”

The new report from the U.S. Centers for Disease Control in Atlanta came one day after a report on an HIV-infected surgeon. An investigation found no evidence of HIV transmission to the surgeon’s patients, 616 of whom were tested for the virus.

“These results support the concept that the risks to patients operated on by HIV-infected surgeons are most likely quite low,” the researchers reported in the issue of the Journal of the American Medical Assn. released Wednesday.

In the case of the dentist, the federal health officials reported that the patient was diagnosed with AIDS two years after having two molars extracted. Her dentist, who is no longer in practice, had been diagnosed with AIDS three months before the operation and had not told his patients.

The woman recalled that the dentist wore gloves and a mask during the operation, as required under standard procedures, the researchers reported. She recalled no exposure to the dentist’s blood or body fluids--a condition necessary for transmission of the virus.

The CDC noted that a comparable virus, hepatitis B, has been known to be spread during tooth extractions.

The researchers said interviews with the woman, her family and friends turned up no other AIDS risk factors such as blood transfusions, intravenous drug use or artificial insemination.

But the researchers cautioned that “such risk factors involve sensitive personal behaviors that may not always be revealed in interviews.”

Finally, the researchers analyzed AIDS virus DNA extracted from blood samples from the dentist and the patient. While the samples of genetic material could be distinguished from each other, they were sufficiently similar to suggest they came from the same source.

“The case reported here is consistent with transmission of HIV to a patient during an invasive dental procedure, although the possibility of another source of infection cannot be entirely excluded,” the CDC reported.

The CDC did not name the dentist or the patient or give other details of the case.

California Medical Assn. guidelines state that transmission of disease by a health-care worker could occur for one of only two reasons: the health-care worker deviates from standard procedure, or certain operations carry an inherent risk of infection.

Routine infection-control procedures in hospitals and doctor’s offices require immediate removal of any contaminated equipment from the area being operated on. Gloves, masks and gowns are required for all invasive procedures.

The CMA guidelines suggest that inherently risky procedures be replaced, where possible, with less risky procedures. Where that is not possible, certain high-risk procedures should not be performed by infected health-care workers, the guidelines say.