非洲草根阶层帮助减少艾滋病

A prominent American epidemiologist Dr. Daniel Halperin is encouraging international health experts to support behavior change as a primary tool in helping to prevent the spread of HIV.

He expresses his views in a new book Tinderbox: How the West Sparked the AIDS Epidemic and How The World Can Finally Overcome It. It’s co-authored by Craig Timberg, the former Johannesburg editor for The Washington Post newspaper.

Cutting edge

The authors say there are relatively inexpensive and even traditional ways of reducing new infections. One is male circumcision -- a practice that they say has already kept infection rates low in places where it’s common.

Washington Post journalist Craig Timberg explained why the disease has made less of an impact in some parts of Africa than others. He made his comments on a recent broadcast of Book-TV on the C –Span television network:

"As transport routes improved, HIV [made] its way into East Africa – Rwanda, Uganda, and parts of Kenya close to Lake Victoria where men are not circumcised," said Timberg.

"That’s because they are from a different ethnic tradition. Rather than coming over from Nigeria and West Africa, they came from the Sudan and down the Nile Valley, so you have millions of men who were not circumcised. When the virus makes its way into that population, suddenly you get this explosive kind of spread –instead of an infection rate of one or two percent of adults, you see 10, 15, and in some places 20 percent of adults.

Among those hardest hit, he says, were the Luo ethnic group in Kenya and the Zulu in South Africa – both which do not practice male circumcision.

Low tech, high rewards

Timberg said the international community responded slowly to studies showing that circumcision was effective, showing a preference instead for high-tech solutions to treat those infected with HIV. But that’s changing, he told an audience at the Foreign Policy Research Institute in Philadelphia:

"Male circumcision science only gets stronger with each passing year as they follow up these guys who were circumcised in 2002-03 for these landmark studies," said Timberg. "They’ve done three randomized controlled trials – the gold standard for medical research. In all three of these cases, they shut the trials down early because the men who were not getting circumcised were getting HIV so much faster than the men who were circumcised that it was regarded as no longer ethnical to keep those trials going.

"In the years since that happened they’ve done long term follow ups," he continued, "Whereas they were saying at first circumcision was 60 percent effective -- as the years pass, the protection goes up: 70%, 75%..".

Fear and compassion

Besides circumcision, Timberg says several countries have mounted effective campaigns to change behavior.

He said new infection rates dropped in several countries, including Uganda and Zimbabwe, long before the availability of life-prolonging drugs.

In Uganda, a campaign by the government of President Yoweri Museveni nearly 20 years ago appealed to public fear and compassion. It included billboards with skulls and crossbones, war drums warning early morning radio listeners about the seriousness of HIV/AIDS, and a commercial featuring the voice of a young girl urging her father to be faithful.

The campaign also urged the adoption of what was called “Zero Grazing”. It encouraged men and women to restrict their number of partners.

"The idea is that when a (tethered) goat is staked at a homestead and he grazes (only) in that spot, it looks like a zero because he can only go so far," explained Timberg.

"This was a message that was clever in part because even if you are in polygamous marriage, zero grazing works for you, too. As long as sexual activity was happening within the “homestead,” that was fine. So what they saw in Uganda was this [notable] decline over the course of five years the average number of partners that people had.

The weight of HIV

He says Zimbabwe and Zaire [now the Democratic Republic of the Congo] also had their own effective grass roots reactions to the threat of HIV/AIDS.

In Zaire, popular pop singer Franco stirred public debate about the disease with his radio hit Attention na SIDA (Beware of AIDS). Franco denied having HIV, though the heavy-set musician lost weight and died within years of his hit.

Subsequent studies found the tune had resonated with the public. One survey of people in 10 cities across the nation showed half of those interviewed said they were familiar with the song, and had reduced their number of sex partners. Meanwhile, a study of over 3,000 health care workers showed those having extramarital relations dropped from 54% to 40% during the peak years of airplay for the Franco hit.

Timberg said about 12 years ago in Zimbabwe, an economic crisis exacerbated by a controversial land reform program meant less money for men to spend in bars and on girlfriends.

Starting the conversation

More importantly, civil society leaders and -- as in Zaire -- pop stars started the country talking about the only way to avoid infection and death: changing sexual behavior.

"The Zimbabweans, shunned and ignored," said Timberg, "have this [surprising] drop in HIV cases. In Zimbabwe as in some other places, they had a singer Oliver Mtukudzi – who had lost a brother and four band members in a span of about sixteen months. He had a song called What Shall We Do (and another called Stay with One Woman). It was less preachy than some of the other songs by some African singers over the years, but it does seem to part of this conversation Zimbabweans were having with one another about what to do about this terrible disaster.

Timberg said that international health surveys showed that between 1999 and 2005, the number of married men reporting sex outside of marriage dropped by 30% in Zimbabwe. The adult HIV rated dropped from a peak of 29% by half.

The co-author of “Tinderbox,” epidemiologist and medical anthropologist Daniel Halperin, credited the change largely to fear, and to the broad participation of civic and religious leaders.

Secret lover

In Swaziland, a popular campaign against HIV used billboards and cellphone messages to warn against multiple partners: One advertisement began with a cell phone message saying “I’m dying to have you.” An accompanying message warned “Why destroy your family ? Your secret lover can kill you.” Other billboards encouraged men to be faithful to one partner and to practice responsible fatherhood.

A USAID-funded analysis of the program found that nearly 90 percent of Swazis queried had heard of the campaign, and a vast majority of them considered changing their behaviors as a result.

The authors of the Tinderbox, Danial Halperin and Craig Timberg, say there’s a subtle bias toward anti-retrovirals and other biomedical approaches.

Prevention as treatment

Today, many health experts favor “treatment as prevention.” Under the strategy, ARV’s are given as a prophylaxis to an uninfected partner in a couple where one already has HIV. They are also given early to those infected by HIV but who do not yet exhibit symptoms. Testing shows early use of ARV’s help prevent the spread of the virus in both those who have been exposed to HIV, and those who have not.

But Halperin and Timberg say the effort is expensive and will be difficult for many local health care systems to handle. Studies also show that many people fail to take toxic drugs until symptoms develop.

The authors say promoting behavior change as well as male circumcision is much less expensive that some of the other approaches, and have roots in local culture.

“If men and women living amid severe epidemics dial back, even modestly, their number of sexual partners,” say the authors, the vast network created by multiple and concurrent relationships collapses. The virus then finds it harder to find new victims, and everyone in the community, they say, is safer.