CDC dared to draw up HIV prevention list

Advisory committee wants to know what works

After 15 years and millions of dollars in research, government health officials should be able to tell the public in simple terms what does and doesn’t work in HIV prevention, says Mark Smith, MD, MPH, chairman of the AIDS Advisory Committee for the Prevention of HIV.

Smith is outgoing chairman of the Centers for Disease Control and Prevention advisory committee. He climaxed his last meeting as the head of the committee by arguing that the time has come for the CDC to issue a list of five or six prevention efforts that are known to be effective against HIV. The request sparked heated debate, but in the end, the committee agreed that coming up with a list would be, in the words of one member, "a fascinating endeavor."

Smith, however, warned that his challenge was more than just an academic exercise and that the CDC’s reputation — and possibly its funding — were at stake.

"Having some scientific basis on which to say what works and what doesn’t work in HIV prevention is central to the credibility of the agency, and I frankly feel like I get both answers every time the question is raised," Smith said.

On the one hand, he said, researchers have learned much about HIV prevention behavior in the past 10 years. Yet whenever Smith asks for a brief list of what works, he said he receives answers such as, "We’re just at the beginning of this and we really don’t know what works," or "We know what works in some populations but not in others."

That response is no longer adequate, said Smith, arguing that the lack of a coherent and persuasive HIV prevention message has lead to legislation that doesn’t necessarily serve public health needs.

"I fear there is the opportunity for misunderstanding. I have seen a couple of areas already — newborn screening, partner notification, counseling and testing — where the policy-makers have made certain decisions that probably would have been opposed by most people on this committee and most in the public health community," he said.

‘I looked in vain for six bullets to give them’

As vice president of the Henry J. Kaiser Family Foundation, Smith’s interest in HIV prevention is tied to his managed care background. Nonetheless, when faculty of the Harvard Univer sity School of Public Health asked Smith for HIV prevention tips at a recent HIV awareness meeting of African-American leaders held at the university, "I looked in vain for six bullets to give them," he said.

Several committee members noted that behavioral research is not a hard science and that HIV is tied up in complex behaviors that vary by culture, education, and ethnic background. Ano ther barrier is expectations, said Helene Gayle, director of the CDC’s Center for HIV, STDs, and TB.

"It’s not so much the information — what works or makes a difference — as the fact that people want it to be 100% forever, and we don’t have anything that is 100% forever," she said. "There is an inability to accept that knowing what works is not going to keep somebody from ever getting HIV."

While acknowledging that HIV prevention is complex, committee member Ward Cates, MD, MPH, senior vice president of biomedical affairs at Family Health International in Raleigh, NC, argued that even marginally effective interventions have a cumulative effect, and when taken together, work for targeted individuals and populations. What is needed, he said, is a combination of prevention efforts similar to combination treatment of HIV.

"We need to think in terms of combination prevention strategies in populations in much the same way that combination chemotherapy works cumulatively in individuals. It’s complex the way combination therapy works, but they [the drugs] work together."

The problem with that analogy is that prevention interventions can’t be monitored with the exactness of, say, viral load. "Is a 5% change in behavior once a week enough? I’m not sure you can come up with that answer," said Neil Schram, MD, an AIDS physician for Southern Permanente Medical Group in Harbor City, CA.

By way of comparison, Schram shared his experience with diabetes research, which has shown that diabetics who take ACE inhibitors can lower blood pressure and thereby reduce their risk of developing end-stage renal disease. Some patients who take inhibitors, however, still will develop end-stage renal disease. Others will die of other complications before becoming afflicted with the disease.

"Millions of dollars are spent on ACE inhibitors, and yet nobody is saying they have to prevent all renal disease — they can’t do that," he said.

The lack of a simple and coherent list of effective HIV prevention measures may reflect a public relations problem among behavioral scientists when forced to explain their work in public forums or to politicians, said committee member Peggy Clark, president of the American Social Health Association in Research Triangle Park, NC.

"What we need is a concise summary of things that appear to work," she said, "but too often I hear scientists explain science to politicians when what they are really looking for is the point."

Marion Secundi, PhD, professor of medical ethics in the department of community health and family practice at Howard University in Washington, DC, raised another barrier to making it simple: job security. "The problem is that on one level what you are asking is to put yourself out of business, because what you are talking about is people’s jobs that wouldn’t be needed if we have a preponderance of evidence that says we know what we are talking about," Secundi said.

The committee will try to formulate a list, but not before it sees how well another group does when it faces a similar tasks early next year. In February, the National Institutes of Health in Bethesda, MD, is sponsoring a consensus development conference on HIV prevention. The purpose of the conference is to reach agreement on several key questions, including:

• How can we identify the behaviors and contexts that place individuals/communities at risk for HIV?

• What methods of intervention reduce behavioral risks at the individual, group, and community levels? What are the risks and benefits of these methods?

• Does a reduction in these behavioral risks lead to a reduction in HIV?

• How can risk-reduction procedures be implemented effectively?

• What research is most urgently needed?

The discussions that emerge from that meeting will help guide the committee in drawing up a list, Smith said.

[Editor’s note: Can you list five HIV prevention efforts that you are confident will work today — and tomorrow? Can you explain them in one or two sentences? If so, AIDS Alert would like you to send them to us. We will tabulate the results and publish them in an upcoming issue. Contact: Skip Connett, Editor, AIDS Alert, P.O. Box 740056, Atlanta, GA 30305. Telephone: (404) 249-7300. Fax: (404) 262-7837.]