Jeanne Talpers hangs up the phone in the Whitman-Walker Clinic basement, shuts her eyes for a second and sighs to no one in particular, "I think he has it." The others in the room, workers on the D.C. AIDS Information Line, nod with sympathy but without surprise. "Did he want to know about symptoms?" says one.

The caller had. Lots of the people who call 332-AIDS, the number for the D.C. AIDS Information Line, which is run out of the Whitman-Walker Clinic, start by asking a question that seems both direct and frustratingly broad: Can you tell me, please, what are the symptoms of AIDS? Others want to know -- in exact percentages, if possible -- what their chances are of getting AIDS if they used to use intravenous drugs. Or if they just tested positive for the virus -- the dreaded "yes" -- but don't feel sick. Or if they had oral sex with somebody a year ago. Later in the calls, sometimes, comes a more urgent question: Do you know if they've found anything yet, I mean, anything like a cure?

The D.C. AIDS Information Line, of course, has no really satisfactory information on any of these subjects.

The Whitman-Walker Clinic, at 14th and S Streets NW in the District, is the kind of place people mean when they praise the gay community for its valor in the day-to-day trench war against AIDS. In existence since 1973 as a gay health clinic, it has expanded to meet the emergency with antibody testing, counseling, educational programs and an array of outside support groups and legal and financial services for the dying and the panicked. There are even a couple of "affirmative action jobs" available to out-of-work AIDS patients.

The information line, funded by a D.C. government contract with Whitman-Walker, is at the nerve center of all these services, taking calls from 11 a.m. to 10 p.m. daily -- sometimes more than 1,000 a month. And so the biggest surprise, in a visit to what is in many ways a clearinghouse of despair, is how cautious and moderate things seem here by contrast to the hysteria outside the clinic windows. In the current atmosphere of compulsion on AIDS containment -- mandatory testing, mandatory contact tracing, "clean" dating clubs -- the volunteers seem almost diffident when it comes to handing out information and advice. But what they do say leaves AIDS sounding less like the unknowably supernatural killer of media familiarity and more like just a tricky infection, something about which a few logical things are in fact known.

"What are the symptoms of AIDS?" The volunteers answering the phone, who have first undergone a several-month training period and frequently meet in a support group to keep up to date, try not to answer this question right away. It's not out of cruelty but because with AIDS, which suppresses the body's defenses and opens the way to other infection, any symptom might be some other disease instead. It's also because, as one volunteer puts it, "If you begin reciting a list of symptoms, a caller in a certain state of nerves will just start manufacturing them."

The main question they do answer -- "How do you get AIDS?" -- brings more difficulties. If anyone still needed proof of the degree to which people's knowledge on this point rests on flimsy and ever-shifting assumptions, it would come from the waves of calls the D.C. Information Line gets after even the most minor media reference to AIDS. In June, when the mainstream media were wrangling over the imminence of the disease's spread to heterosexuals, "my typical call was probably from a heterosexual woman who was a little promiscuous in college five years ago," says volunteer Valerie Ploumpis. When the Phil Donahue show aired a suggestion that condoms might not be 100 percent safe, callers flooded the line with doubts about safe sex. When The Post ran a speculative piece on transmission by mosquito, the mosquito calls went on for days.

To counter this confusion, the volunteers start with absolute basics. "We used to talk to people about high-risk and low-risk behaviors," says volunteer Teresa Barry, an editor and a one-year veteran of the hot line, "and I was never comfortable with that." Now they "put the power back in the callers' hands" by walking them step by step through what science knows for sure: the virus is found in its highest concentrations in blood and semen; it dies quickly without "a hot, moist environment" (in other words, doorknobs and toilet seats are out); skin, like a condom, is a barrier, and the virus cannot get through unless there is a break. Compared to airborne or dirt-borne germs, they reiterate, the AIDS virus is very difficult to catch.

To get more specific than this, volunteers say, would do more than take them onto scientifically disputed ground. Specific prohibitions and precise percentages can be a way for callers to avoid confronting the hard questions of their own behavior, what Barry calls "the immunity mindset": people listening for a detail that seems to rule them out, "and then, click! That's all they hear." By stressing that these details still aren't known, the volunteers can hit harder their best advice, which is to urge safe sex. They don't even declare outright whether the caller should get tested -- but, through a standard counseling technique called "active listening," try to elicit people's own judgment of what to do, based on the information. "No one," says Barry, "is going to give them permission to do anything."

People fight this. They say things like, "All right, I understand, but what would you do?" The volunteers are supposed to answer, "It's not important what I'd do. You have more information about your life." For the hardest and most painful calls, those from people who have just tested positive and don't know what on earth to do, there are only referrals and suggestions for keeping healthy: find a support group, see your doctor, get off drugs or alcohol if you're on them. The shelves above the lumber table top with the telephone lines are stuffed with referral lists.

"What are the symptoms of AIDS?" "It sounds to me," says a volunteer, "as if you really need to know how you get AIDS." They talk. It's amazing how this careful, almost reluctant, doling out of sensible information dispels the fears and irrational giggles like a mist. The most jittery of visitors soon picks up the volunteers' sense that this virus is just an illness after all, though a tragic one -- not a virulent, incomprehensible force, not a supernatural plague coming from nowhere, and not, especially, an occasion for abandoning all logical response. "Sometimes," says Talpers, "by just saying the words you're scared of, you kind of take the edge off it." A disease we can neither fathom nor cure may be fearsome, but it is by no means outside human experience. Not many generations ago, grappling with such fears, without medicine, was an ordinary part of life. This time again, when irrational fears outrun science, sensible information is the medicine we most need.

The writer is a member of the editorial page staff.