SPRINGFIELD, Ill. (AP) _ Illinois health officials have decided to track people with AIDS by a special code instead of by their names.

The decision Thursday by the Illinois Public Health Department comes as more and more states adopt measures that focus on protecting the public at the expense of AIDS patients' privacy.

The new Illinois plan was hailed as a victory by HIV activists who were concerned that an earlier proposal to catalog patients by name would endanger their privacy.

At least 31 states already require that the names of people who test positive for HIV be reported to health officials, and Illinois had been as expected to join the group.

In addition, at least 29 states have passed laws making it a crime to knowingly transmit or expose others to HIV, one-third of which have adopted the laws in the last two years, The New York Times reported today. Similar measures are pending in 16 other states.

Experts said the laws reflect a shift in attitude toward people with the virus and a departure from legislation that sought to protect the civil liberties of AIDS patients. Powerful new treatment drugs also have contributed to the perception that the deadly disease is simply a chronic condition, they said.

``Clearly, there is a backlash,'' Lawrence Gostin, a director of the Georgetown University-Johns Hopkins University Program on Law and Public Health, told the Times.

``We are now treating the disease as more of a problem of criminal law and coercive state powers than one to do with health and medicine.''

The Illinois plan will take effect in July if it wins legislative approval. If the state decides the pilot program doesn't work within two years, it will implement the original plan to report names of HIV carriers.