Every year, about 100 Americans get killed by lightning. A decade into the AIDS epidemic, a grand total of three people are thought to have contracted the virus from a health-care worker. Yet in the months since federal officials reported those three extraordinary cases-all linked to a deceased Florida dentist named David Acer–infected physicians have become a national obsession. Hospital boards, professional associations, federal agencies and state legislators are debating new restrictions on HIV-positive doctors. The usual demand–that surgeons and dentists disclose their HIV status so that prospective patients can make “informed choices”-is more problematic than it sounds. Such rules can put capable physicians out of work without really enhancing patients’ safety. But if a court ruling handed down in New Jersey last week is any indication, mandatory disclosure is the wave of the future.

In the New Jersey case, a state court ruled that The Medical Center at Princeton was right to demand that an infected ear, nose and throat specialist get written consent from patients before operating on them. The surgeon, Dr. William Behringer, had had his blood tested at the hospital’s emergency room in 1987, after a period of unexplained illness. When he tested positive for HIV, word spread quickly through the hospital and the community. Behringer soon felt better (AIDS-related symptoms wax and wane), and the hospital’s medical staff agreed there was no reason to restrict his practice as long as he observed standard infection-control procedures. Even so, the hospital’s president and board of trustees adopted a rule requiring written consent from his prospective patients, effectively putting him out of business. Behringer sued in 1988, charging that the hospital violated a state law that bars discrimination against disabled people when there is no reasonable probability of harm to others. He died in 1989 but his estate pursued the case.

In last week’s ruling, the court agreed that the hospital violated Behringer’s rights as a patient by failing to keep his test results private. His estate will receive damages for the breach of confidentiality. Yet, in the same ruling, New Jersey Superior Court Judge Philip Carchman heartily endorsed the policy that restricted Behringer’s surgical practice. “The ultimate risk to the patient is so absolute, so devastating,” the judge wrote, REPORTERS “that it is untenable to argue against informed consent.” Legally, the decision has no bearing outside the court’s New Jersey jurisdiction, but it sends a loud message to hospitals around the country as they weigh the rights of infected doctors against those of worried patients.

The question is whether the worry is warranted. What are a patient’s chances of getting infected by a health worker? Scientists at the Centers for Disease Control (CDC) have calculated that a patient with an infected surgeon faces odds of between 1 in 42,000 and 1 in 417,000. The estimates proceed from assumptions about how often surgeons cut themselves in the course of an operation. The same highly speculative model places the odds of a dentist-to-patient transmission at between 1 in 263,000 and 1 in 2.6 million. The truth is, no one really knows. Nor does anyone know just how David Acer might have infected his three patients. Researchers have looked for similar incidents, but they have yet to find one. In 1986, 75 patients of an infected Air Force surgeon tested negative for the virus. In 1989, Tennessee health officials examined 616 former patients of a Nashville surgeon who had died of AIDS. One had antibodies to the virus-but he also had a history of intravenous drug use. This year the Medical College of Georgia tested 146 patients of a dental student who had HIV antibodies. Not one tested positive.

If an epidemiological survey had the emotional pull of a human story, the whole affair might end there. But it doesn’t. The nation has been transfixed by the story of Kimberly Bergalis, a wholesome-looking 23-year-old who is suffering from the deadly illness she contracted in Acer’s examining room. In response to growing public alarm, several hospitals have contacted former patients upon identifying an infected surgeon. Dr. Robert A. Engel, an orthodontist in Wellington, Fla., closed his own practice last month, and notified 800 patients that he had been diagnosed with AIDS. The American Medical Association and American Dental Association have called on infected surgeons and dentists to divulge their HIV status, even if it deprives them of a living. AIDS activists and many public-health experts are outraged. They say such guidelines simply distract attention from other problems, such as physician incompetence, that pose far greater risks to patients.

Officials at the CDC are ironing out the details of their own, less stringent guidelines, now circulating in draft form. The CDC proposals don’t call on health workers to disclose their status. They recommend only that anyone performing invasive procedures be tested, and that those who test positive refrain from risky operations or secure approval from expert review panels. But the CDC’s proposed recommendations raise as many questions as they answer. What would keep hospital trustees from overruling expert panels? How long would it take for insurers to stop covering hospitals that openly let infected surgeons practice? CDC, the medical profession and the public won’t stop debating these issues anytime soon. But last week’s events suggest they won’t be the final arbiters. As usual, that honor will fall to the courts.