AIDS at 30
Thirty years ago Sunday, a brief report in the Morbidity and Mortality Weekly Report described five cases of a rare form of pneumonia calledPneumocystis carinii in five young Los Angeles men, "all active homosexuals." The cases were noteworthy because the men had previously been healthy, though their particular pneumonia had only been seen in people with severely depressed immune systems.
Within a month, a second report had identified 54 young gay men with a rare cancer known as Kaposi's sarcoma, another disease that had been almost unknown in young men. And by the following summer, the mysterious disease underlying these reports had a name: acquired immune deficiency syndrome, or AIDS.
AIDS was a murderous, mysterious delinquent that emerged seemingly out of nowhere. Transmitted primarily through sexual activity and blood, it mowed down whole communities of young gay men, tore through a generation of intravenous drug users and made orphans of millions of the world's children.
In the 30 years since its first recognition, AIDS has killed nearly 30 million people worldwide, including more than 615,000 in the United States. Today, an additional 34 million people — including nearly 1.2 million in the U.S. — are living with the virus that causes the disease, human immunodeficiency virus, or HIV. This year, 1.8 million of them will die, including about 17,000 in this country.
The identification of HIV in 1983 brought the promise of a quick fix for the problem, a vaccine that would block transmission. Sadly, that promise has not materialized. The shifty virus mutates so rapidly and has so many ways of entering the white blood cells that are its primary target that vaccine researchers have had only limited success.
The best results so far were from a 2009 trial in Thailand that reduced new HIV infections by a modest 26%. The results hinted that a vaccine might eventually be possible, but suggested that researchers still had a long way to go to produce one that is useful.
Some progress has been made on other fronts. At least 30 different drugs are now commercially available to combat HIV, and cocktails of those drugs — including the particularly effective class of drugs known as protease inhibitors — have transformed HIV from a death sentence into a chronic, manageable disease.
But protease inhibitors, approved by the U.S. Food and Drug Administration in 1995, are expensive and are thus not available to most of the afflicted. Though the use of the drugs worldwide has increased twenty-two-fold since 2001 and a record 1.4 million people started taking them in 2010, according to the United Nations, fewer than half of the 15 million people who should be on them actually get them. Even in the wealthy United States, there are long waiting lists in many states for access to the lifesaving medications.
As difficult as it has been to attack the virus medically, some say the bigger challenge is finding a way to address the social attitudes and economic realities that have helped make AIDS a worldwide pandemic. Hard-fought gains are continually lost as the audiences for campaigns on prevention techniques such as using condoms and not sharing needles become blase about HIV and new generations enter the risk pool. In the United States, 50,000 people become infected with the virus each year — a figure that has scarcely budged in the last 12 years.
Today, the most new infections occur among people under the age of 30, a generation that has never known a time without effective HIV therapy and who may not understand the significant health threat HIV poses, said Dr. Thomas R. Frieden, director of the U.S. Centers for Disease Control and Prevention.
Transmission rates among gay men, long in decline, have rebounded in recent years as the prominence of safe-sex messages wanes, complacency sets in, and gay youth who have no memory of AIDS' once-deadly grip on their community adopt risky sexual practices. Although gay and bisexual men represent just 4% of the American population, they account for more than half of all new infections each year, according to the CDC.
A recent CDC study found that nearly 20% of gay and bisexual men in major U.S. cities are HIV-positive. According to the L.A. Gay & Lesbian Center, 82% of HIV-positive individuals in Los Angeles County are gay and bisexual men.
Changing any type of maladaptive behavior is hard. "And when you talk about a disease that involves sex and drugs, you take those behavioral challenges and multiply them ten- and twentyfold," says Kevin Robert Frost, chief executive of the American Foundation for AIDS Research.
The challenge is made harder by the success of HIV/AID medications: As those with HIV live longer lives with treatment, the pool of people who can spread the virus expands yearly. Persistent religious objections to condom use, resurgent political opposition to needle-exchange programs, and stubborn health and economic disparities that keep many women, minorities and the poor from getting help exacerbate the difficulties.
Significant strides have been made in prevention, however, especially in the last two years. Campaigns aimed at curbing risky sexual behavior, promoting HIV testing for those at risk and discouraging IV drug users from sharing needles all have made progress — albeit fitfully.
According to a United Nations report issued Thursday, the global rate of new HIV infections fell by 25% from 2001 through 2009. In India and South Africa, the countries with the largest number of people living with HIV, new infections fell by 50% and 35% respectively.
Medications will soon play a major role in prevention. Many studies over the years have shown that giving anti-AIDS drugs to pregnant HIV-positive women is extremely effective in preventing transmission to their infants. In the United States, the incidence of infection in newborns is approaching zero.
A 2006 study among more than 8,000 men in Kenya and Uganda showed that circumcision can reduce transmission of the virus from their HIV-positive female partners by 56%. A study last year in nearly 900 women in South Africa showed that faithful use of a vaginal gel containing the antiretroviral drug tenofovir reduced the women's risk of contracting the virus by 54%.
Researchers also have great hopes for a relatively new concept known as pre-exposure prophylaxis, in which uninfected people take antiretroviral drugs in hopes of blocking new infections. A November 2010 study of nearly 2,500 high-risk gay men, mostly in Africa, showed that taking a pill called Truvada containing two antiretroviral drugs could block new infections by an average of 44%, and by more than 70% if the men took the drugs according to a strict regimen.
And just last month, a trial of nearly 1,800 heterosexual couples in Africa and Asia showed that giving antiretroviral drugs to the HIV-positive member could reduce transmission to the uninfected partner by as much as 96%.
Dr. Jay Levy of UC San Francisco, one of the researchers who first identified HIV in a lab in 1983, now spends his days trying to isolate, distill and reproduce a naturally occurring protein produced in minute quantities by a small number of people that prevents the virus from infecting white blood cells. It is, he says, a diabolically complex challenge.
Yet Levy speaks with weary admiration about the work of the researchers and public health officials who are trying to figure out what message will induce sexual partners to use condoms and anti-microbial gels consistently, or to influence cultural practices and attitudes that sustain the spread of HIV.
"The behaviorists really have a tough job," Levy said. "They're the ones doing the real science."
That's discouraging, because in places like sub-Saharan Africa, where two-thirds of the world's AIDS patients live, and in disadvantaged corners of the United States, where infection rates have remained stubbornly high, any "cure" is likely to be prohibitively costly and painfully slow to arrive. For the foreseeable future, the front lines of the fight against AIDS will remain behavior change to stem the spread of infection.
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