When a 30-year-old AIDS victim came to Houston and allegedly vowed to continue having sex with strangers, he was threatened with arrest and finally persuaded to enter a hospital for treatment. He died Nov. 17, but his case spurred the Texas Board of Health to make an initial ruling this past weekend that AIDS patients may be quarantined if they do not cooperate with authorities.

The board's 12-to-5 decision, likely to be made final after a 30-day period for public comment, came about because "we have a moral obligation to protect the people of Texas against a disease that is 100 percent fatal," said board member Dr. Barry Cunningham.

Virginia health officials are drawing up a contingency plan to determine whether to implement some sort of quarantine against "incorrigible" AIDS patients, such as prostitutes, who may expose others to acquired immune deficiency syndrome through sexual relations.

And in Delray Beach, Fla., a judge imposed an unusual six-week sentence against a 20-year-old woman with AIDS who was charged with prostitution. He put her under house arrest, ensuring compliance with an electronic beeper that would alert authorities should she attempt to venture outside.

In the past six months, there have been signs of a greater willingness among health and law enforcement authorities, as well as politicians, to consider stronger actions in the name of public health that would limit to varying degrees the rights of AIDS patients or people with the highest risk of getting the disease.

Such controversial steps could include quarantine of uncooperative, sexually active AIDS patients, criminal sanctions, employment or educational restrictions (despite federal guidelines to the contrary) on those infected with the AIDS virus, more extensive use of the AIDS antibody blood test, shutting down sex establishments frequented by homosexual men, tracing sexual contacts of AIDS patients and keeping confidential state lists of known AIDS carriers and victims.

"People are talking about coercive methods much more now," said Dr. James O. Mason, a top Reagan administration health official. "Six months ago, it was not mentioned by anyone. My concern is that we act on the basis of the science of the disease and not just concern about the disease." But he added, "It's a political judgment how far society wants to go to stop the spread of a disease that is spread by consenting adults."

Mason recently resumed his post as head of the Centers for Disease Control after a year as acting assistant secretary for health at the Health and Human Services Department. He has had his staff review the government's legal authority to act in public health emergencies and has asked a Harvard University health law professor to prepare a report on possible actions and their consequences.

Lawyers for the American Civil Liberties Union and gay rights groups also are studying the legal questions involved in possible mandatory actions, including quarantine.

"AIDS poses one of the great civil liberties crises of the late 20th century," said Thomas Stoddard of the ACLU. "It tests our commitment to fundamental principles of compassion, fairness and due process. It is a medical crisis as grave as any social crisis faced by this country in fifty years."

"We will selectively use very firm public health authority when it makes medical sense," said Kristine Gebbie, Oregon state health administrator and head of the AIDS task force for the Association of State and Territorial Health Officials. "The protection of public health does interfere to a certain extent with individual choice."

More than 15,000 Americans have been reported to have AIDS since 1981 -- half of whom have already died. It is estimated that more than a million other Americans, most of them apparently healthy, have been exposed to the virus and may be infectious indefinitely. These carriers may be far more infectious, in terms of active AIDS virus, than AIDS victims are.

Amid the growing concern about AIDS, a few cities and states have enacted laws to protect the rights of AIDS victims. Los Angeles, San Francisco, Hayward and West Hollywood, Calif., have passed antidiscrimination laws on behalf of AIDS patients, while California and Wisconsin have passed legislation protecting the confidentiality of those who test positive on the AIDS antibody blood test, according to Ron Najman of the National Gay Task Force.

The most extreme measure now contemplated to halt AIDS' further spread is quarantine, the detention or restraint of individuals suspected of carrying the disease.

While quarantine was once a standard approach to diseases believed infectious, better understanding of disease, improved sanitation, vaccines and drugs have made human quarantine a largely outmoded public health tool.

The one instance in which quarantine is still regularly used involves the occasional tuberculosis patient who poses a public health threat by refusing to take the medication that now controls this airborne illness. Health departments may involuntarily hospitalize such people, but usually do so only for a couple of weeks while the medication takes effect.

Most states have laws granting health officials sweeping powers to act to protect the public health as they see fit. Some states also have little-used venereal-disease laws that make it a criminal offense, usually a misdemeanor, to infect another person knowingly or negligently through sexual contact. At the federal level, existing law gives the surgeon general, with the approval of the HHS secretary, broad power to prevent the spread of diseases across state or national borders.

"The police powers affecting the control of communicable diseases are very far-reaching . . . . The question is not whether you have the power, but whether it is advisable or appropriate to use it," said Frank Grad, a Columbia University law professor who helped to write New York City's health code.

There is no evidence that AIDS is transmitted casually, such as by coughing or sneezing. Instead, certain intimate acts, such as exposure to bodily fluids through sexual contact or through contaminated needles or blood, seem to be necessary to acquire the virus that causes the disease.

And unlike infectious diseases in which there is a short waiting period to see whether an exposed person becomes ill, AIDS has an unusually long incubation period of several years before symptoms appear.

Large-scale quarantine attempts, if considered, would not be effective unless both victims and suspected carriers were detained. But first, the entire U.S. population would have to be screened to see who is carrying the virus -- and this would need to be repeated regularly. Because there is no treatment, those found to be infectious would have to be detained indefinitely.

While officials shun this scenario as impractical and unnecessary, publicity about extreme cases of alleged sexual promiscuity among some AIDS patients, or those who may carry the virus, has put many public health officials on the spot. The controversy has been fueled politically by individuals and groups, such as the Moral Majority, who have raised the issue of some form of quarantine against AIDS.

At the national level, the government has issued school and workplace guidelines that emphasize that AIDS is not spread through casual contact and has emphasized voluntary changes in sexual behavior to slow AIDS' spread. Mason said he has had private discussions with individuals who complained that he was not doing enough.

"I was told I ought to react more to this epidemic that is spreading throughout the U.S.," Mason said. He said people asked him whether he was "obligated to quarantine everyone" with AIDS. Any large-scale AIDS quarantine proposal, he said, would be as "ridiculous as banning automobiles or preventing the sale of alcohol. Are we willing to ban cigarettes?"

But he added, "Every large community is going to find people so irresponsible that some sort of coercive action will have to be taken. Appropriately applied, it's reasonable to talk about action against individuals. One person's livelihood is not worth infecting many other individuals."

Texas served as a lightning rod for the AIDS quarantine issue when the state health commissioner, Dr. Robert Bernstein, announced in October that he was considering possible use of quarantine as a tool to "control an individual who warrants it in the interest of protecting the public."

Following the Texas board's decision on Saturday, the Associated Press quoted Bernstein as saying, "This does not deal with the average AIDS patient. This is not aimed at a disease, it is aimed at individuals who have the disease and might be incorrigible in a public health way. Whether we'll use this, I don't know."

The quarantine power would be used only as a "last resort," Bernstein said. Local health officials would have to get the state commissioner's approval to isolate an AIDS victim who refused to curtail sexual activity or drug use.

The board also tentatively approved a rule that would require tags on the bodies of people killed by AIDS or certain other contagious diseases, to warn medical personnel and funeral home workers.

Texas appears to be the first state to add AIDS to its list of diseases subject to quarantine, according to George Degnon of the Association of State and Territorial Health Officials. "Generally," he added, "most states can quarantine without any specific disease authority" by acting under their general emergency health powers.

Degnon said he expects that next year, "Many states will be getting a little more firm in their approach to AIDS."

In Virginia, an outside panel of medical specialists met last month to provide the health department with direction on dealing with AIDS, including "quarantine, how it should be used and would it be effective" on a case-by-case basis, said Dr. Robert Stroube, assistant state health commissioner.

Other health and legal specialists are wary of even raising the subject of quarantine as an individual control measure. They say they fear that talk of coercive action or invasion of privacy may drive some individuals underground. Cooperation from AIDS patients and so-called risk groups is crucial to government studies of the disease and to voluntary educational programs.

Critics also worry that there is a slippery slope between quarantine action against "incorrigible" individuals and coercive action against certain groups considered as high risks for carrying AIDS, such as drug abusers, prostitutes or sexually active homosexual men.

Citing the internment of tens of thousands of Japanese-Americans during World War II, Stoddard of the ACLU said he worries that fear and panic can provoke extreme actions that normally are unthinkable.

He said attempts to control irresponsible behavior should be made through the criminal code, rather than through health codes. "I would far prefer the state dealing with these issues through criminal proceedings, because there is greater assurance of fairness and due process. There is much greater danger the state will abuse its power under the quarantine and commitment statutes," in which the process is swifter and the legal protections less encompassing, Stoddard said.

Health officials such as Dr. Robert Benjamin of California argue that the answer is better counseling, not coercion, of infected individuals, combined with mass education. As head of the communicable diseases office for Alameda County, across the bay from San Francisco, he rejected quarantine of an AIDS patient who was having one-night stands and not telling his partners he had AIDS.

"We can do such a thing. We have that power. We have done such a thing with TB tuberculosis patients who refused to take medication. Why do it in the case of TB and not in the case of an AIDS patient? "First of all, you don't have to consent to anything to get TB. You just have to breathe in the air . . . . The second point is that to quarantine this one individual would not be effective in stopping the spread of this disease. There is more than one of him out there" -- those who know they have the disease and many more who don't know they are carriers, Benjamin said.

To quarantine one person "would not make a dent in the whole outbreak . . . . If everyone felt that now this AIDS patient is off the streets, now it's safe to have sex without taking precautions, that's crazy."

Instead, Benjamin said, "It's each individual's responsibility to be damn certain that if they choose to go to bed with some somebody they are protected," not only by choosing sex partners carefully but by engaging in safer sexual practices, including the use of condoms.

He is trying to educate the public through the schools, the news media, even through community billboard messages that say -- in Chinese, Spanish and English -- "It's not who you are, it's what you do. Don't share needles, don't share partners, don't share AIDS."