Previously, federal health officials recommended emergency drug treatment only for health-care workers accidentally stuck with a needle, splashed in the eye with blood, or exposed in some other way on the job. That recommendation was first made in 1996.
The Centers for Disease Control and Prevention expanded its guidelines to rape victims and many others Thursday. It said treatment should start no more than 72 hours after a person has been exposed to the virus, and the drugs should be used by patients for 28 days.
It is a major shift away from a policy that some doctors had called unconscionable and that put the United States years behind much of Europe and other nations.
"The severity of the HIV epidemic dictates we use all available tools to reduce infection," said Dr. Ronald Valdiserri of the CDC.
He stressed that emergency drug treatment is a "safety net," not a substitute for abstinence, monogamy, and the use of condoms and sterile needles.
"It is clearly not a 'morning-after pill,"' he said.
People accidentally exposed to the AIDS virus are usually given a three-drug combination that includes AZT and 3TC.
In tests on primates, drug cocktails prevented infection with the monkey version of HIV 100 percent of the time if given within 24 hours of exposure to the virus, and 52 percent of the time if administered within 72 hours, said Dr. Charles Gonzalez, assistant professor of medicine at New York University School of Medicine and a member of the New York State AIDS Institute medical guidelines board.
However, there is no data from clinical trials on how effective the drugs are in stemming HIV infection in people.
The new guidelines do not bind the U.S. government to pay for the treatment regimen through Medicare or Medicaid, and no federal money has been allocated to help doctors and health departments carry out the recommendations.
European countries, Australia and Brazil have long had guidelines calling for the use of HIV drugs to prevent infection in rape victims. Without a national policy in the United States, New York, California, Massachusetts and Rhode Island and cities such as San Francisco and Boston came up with their own such guidelines.
"It's unconscionable they didn't have a policy for rape victims. It's just ludicrous. They knew they were well behind the curve," Gonzalez said.
The CDC said it hesitated to recommend wider use of AIDS drugs because it did not have enough information on their effectiveness. But the agency said better information has been gathered over the past several years from animal and lab studies and from state and city programs that offer HIV drugs to rape victims and others.
But Gonzalez suggested that the CDC may have been stymied by a conservative administration in Washington from making such a recommendation from earlier.
"This may be a 'red state, blue state' issue, where states such as Massachusetts, New York and California are willing to discuss this matter in terms of rape and what happens to consensual adults," Gonzalez said.
The CDC said the regimen is not recommended for habitual drug users who share needles, or for people who frequently engage in risky sex. Those people would have to take medication practically nonstop, which the health agency does not endorse.
By Daniel Yee