Research shows where more AIDS treatment is needed in San Francisco

From The New York Times:

The map of San Francisco in the city’s health department is bathed in shades of blue. The color, usually associated with the city’s liberal politics, has a different import on the map. A light shade covers most neighborhoods. A slightly darker one covers the Castro, the center of the city’s gay culture.

And, like an elongated, bearded profile, a dark stain covers Potrero Hill and Bayview. It shows where the sickest AIDS patients live. Many are untreated. The map is the product of a groundbreaking effort to identify where care should be focused.

The research combines medical records and epidemiological tools to show the intensity of the illness, measured by individual’s viral load, the number of viral particles in a patient’s bloodstream. The ultimate goal is to provide treatment and stop transmission of the disease.

Using the data of individuals’ viral load levels, the city can track where the virus is circulating and focus attention on the deepest reservoirs of H.I.V. Successful anti-retroviral treatment reduces the load in an individual so it is undetectable in the blood. The less virus in the blood, the lower the chance of infecting others.

Dr. Grant Colfax (pictured), director of H.I.V. prevention and research in the Department of Public Health, calls San Francisco’s mapping of the viral loads measured from 2005 through 2007 “a thermometer.”

“We’re taking an individual marker and making it a marker for community health,” Dr. Colfax said.

Other communities have mapped the presence of H.I.V., but those have been basic efforts: counting the number of H.I.V./AIDS cases in a geographical area. In effect, those efforts show the surface of the water; the new effort shows the water’s depth.

“H.I.V. is fully treatable and preventable,” said Dr. Julio Montaner, president of the International AIDS Society and head of the division of AIDS at the University of British Columbia. “We have not been able to fully control H.I.V. in developed areas of the world to the extent our knowledge would allow.”

“These hot spots are perpetuating themselves,” Dr. Montaner said, “increasing infection in marginalized communities. This is unacceptable. As long as we don’t deal with that problem, the reservoir of H.I.V. will ensure that we’re promoting the continued spread of H.I.V. in perpetuity.”

San Francisco’s approach, he said, is important because “you can identify hot spots where, in all likelihood, most transmission is occurring.”

Dr. Colfax worries about disparities both in viral load and in care. The Castro, for example, has more H.I.V. cases, but individuals in lower-income neighborhoods tend to have higher viral loads, the new research shows.

San Francisco has more than 15,000 reported cases of H.I.V./AIDS. Those numbers continue to rise. The new findings show that the sickest individuals tend to be African-American, homeless and transgender. The viral loads of African-Americans are about one-third higher than that of Latinos or whites.

“One of the biggest tragedies is our failure to really deal with this in the African-American community,” said Dr. Paul Volberding, a professor and vice chairman of medicine at the University of California at San Francisco Medical School, who treated patients before the disease even had a name.

The results of the mapping were not surprising to James Loyce, executive director of Black Coalition on AIDS in San Francisco. “This scientific evidence supports the community’s notion,” Mr. Loyce said.

Historically, he said, sections like Potrero Hill have felt “benign neglect,” suspecting that services were geared to the Castro, where more H.I.V.-infected people in the city live.

Mr. Loyce said, “There is no sound-bite answer.” The sickest people of color, he said, have many issues: violence, heart disease, diabetes, obesity and the preceived stigma of homosexuality.

“It’s not that it isn’t there,” Mr. Loyce said, “but the belief system is that it isn’t. On Third Street, if you approach young brothers to talk about H.I.V., it will be a short conversation.”

In the early years of the epidemic, H.I.V./AIDS was tracked by the number of monthly deaths. With effective medicines, it became a chronic disease. And as diagnostic tools improved and fear of the illness dissipated, it was easier to track patients’ health. H.I.V. patients’ viral load numbers are reported to the state, but until now no one had tracked communal viral load.

The mapping in San Francisco is “ the next step in tracking the epidemic,” said Mark Cloutier, chief executive of the San Francisco AIDS Foundation.

Dr. Colfax, the city’s senior investigator, agreed, saying: “If any place is able to reduce infections by treating people effectively, San Francisco should have the best chance. We’re hoping it will be a model.”

Others are paying attention. Commending San Francisco for its “novel approach,” Dr. Irene Hall, the chief of H.I.V. surveillance for the federal Centers for Disease Control and Prevention, said via e-mail that the agency was considering expanding viral-load mapping nationwide.

Dr. Moupali Das-Douglas, the lead investigator on the mapping project, said: “If you’re monitoring the epidemic by just following the number of cases there are, you haven’t prevented new cases. If you have a marker upstream that may predict new cases, you can know where to target your services to prevent transmission.”

Michael Petrelis, an AIDS blogger and self-proclaimed provocateur, said, “It’s feeding two birds with one seed, helping a patient extend his life by keeping his viral load down, and that in turn makes him less infectious.”

Despite the fact that the city’s population is well-educated, about 800 residents contract H.I.V. every year, Dr. Colfax said. There are those who know they are ill but do not avail themselves of care. And 15 percent to 20 percent of the H.I.V.-positive population does not know it is positive.

The new study found that city residents with H.I.V. had an average of 22,000 H.I.V. particles in their blood. The health department wants to reduce that to undetectable levels — below 50.

“I like to think of the city the way I think of an individual patient sitting in front of me,” Dr. Das-Douglas said. “The more people I start on medication, the more people will be virologically suppressed and the less likely they will be to transmit H.I.V..”

The city’s decisions on how to act on the new information will be controversial, all involved agree.

Officials must decide whether to shift services, create pocketed marketing campaigns or go directly to the individuals with the highest viral load and offer them appropriate care. But going to individuals could feel like “a police state” and cause some to run away, Dr. Montaner said.

Dr. Colfax said, “You have to balance confidentiality with the fact that nobody in San Francisco should be walking around with a viral load of 100,000.”

The medical community once believed that if a patient began treatment too early, the effectiveness of the medications could wear off. And there were severe side effects. “As the treatment has gotten easier and less toxic, those equations need to be rethought,” Dr. Volberding said.

“One of the big reasons for prescribing medications,” he said, is to protect the public.

Dr. Colfax must balance individual and communal care. “I think we’re asking the right questions,” he said. “Now the issue is, What are the answers?”