Higher Rate of New HIV Cases, HIV in US Blacks Underscores Need for National AIDS Strategy, Cellulose Gel May Increase Vaginal HIV Transmission

September 1, 2008

In the United States, 56,300 new HIV infections occurred in 2006, according to the CDC’s first national estimate of HIV incidence based on direct measurement. The CDC released the report July 26 at the 17th International AIDS Conference in Mexico City (Stannard MB. San Francisco Chronicle. August 3, 2008).

Higher Rate of New HIV Cases
In the United States, 56,300 new HIV infections occurred in 2006, according to the CDC's first national estimate of HIV incidence based on direct measurement. The CDC released the report July 26 at the 17th International AIDS Conference in Mexico City (Stannard MB. San Francisco Chronicle. August 3, 2008). The previous estimate of 40,000 new infections annually had been based only on new diagnoses; this method was limited because it did not take into consideration that years may have elapsed between a patient's infection and diagnosis. The revised estimate is based on a new CDC-developed testing method that differentiates between infections acquired recently (within about the previous 5 months) and long-standing infections.

The new estimate was based on 6864 patients in 22 states among whom 31% had recently acquired HIV, the CDC reported. By extrapolation, the incidence of HIV infection was 22.8 cases per 100,000 population in 2006. Using the new data, researchers estimated HIV incidence peaked in the mid-1980s at approximately 130,000 new infections annually and reached a low of about 50,000 in the early 1990s. Infections increased in the mid-1990s, declined slightly after 1999, and have remained stable since.

Incidence declined among heterosexuals and injection drug users while it increased steadily since the late 1990s among men who have sex with men, who accounted for 53% of new infections in 2006. Blacks had the largest share of new infections (45%), and although new infections among blacks peaked in the late 1980s, the rate was still 7 times that of whites in 2006. More infections also occurred among people younger than 30 years than in any other age group, the CDC said. The relative stability in the rate of new infections suggests that as more people with HIV live longer, healthier lives, they are also taking steps to prevent the spread of HIV, said Dr Kevin Fenton, director of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.

The full report was published in the Journal of the American Medical Association (Hall HI, Song R, Rhodes P, et al. Estimation of HIV incidence in the United States. JAMA. 2008;300:520-529). For more information, visit http://www.cdc.gov/hiv/topics/surveillance/incidence.htm. [CDC HIV/Hepatitis/STD/TB Prevention News Update, Monday, August 4, 2008]

Cellulose Gel May Increase Vaginal HIV Transmission
Because more than 50% of adults with HIV/AIDS in sub-Saharan Africa are women, there is an urgent need for female-initiated methods of HIV prevention. Newly published research, however, reports a setback in the effort to formulate a vaginal gel that prevents transmission of the virus (Reuters Health. July 30, 2008). The candidate gel, formulated with the HIV entry inhibitor cellulose sulfate, was found ineffective in preventing transmission and may have increased the risk of HIV infection.

At 3 sites in Africa and 2 in India, lead author Dr Lut Van Damme and colleagues assessed HIV acquisition in 1398 high-risk women who were randomized to use either the gel (case subjects) or a placebo (controls) an hour before intercourse for 1 year.

Interim analysis suggested the gel more than doubled infection risk (hazard ratio, 2.23; P = .02), although no significant difference between case and control results was noted in the final analysis (hazard ratio, 1.61; P = .13). The gel had no apparent effect on gonorrhea or chlamydial infection. The evidence of increased risk led the study's monitoring committee to shut down the trial prematurely.

"Despite the disappointing outcome of this study and recently halted vaccine trials, . . . the search for HIV prevention methods that can be initiated by women must continue to help stem the tide of infection in highly vulnerable populations," the authors concluded.

The full report, "Lack of Effectiveness of Cellulose Sulfate Gel for the Prevention of Vaginal HIV Transmission," was published in The New England Journal of Medicine. 2008;359:463-472. [CDC HIV/Hepatitis/STD/TB Prevention News Update, Thursday, July 31, 2008]

High Incidence of HIV in US Blacks Underscores Need for National AIDS Strategy
Black America, if viewed as a separate nation, would rank 16th highest among the world's countries for the number of people living with HIV, according to a recent report (Altman LK. New York Times. July 30, 2008). Indeed, the number of African Americans with HIV is larger than the infected populations of 7 of the 15 nations that receive support from the President's Emergency Plan for AIDS Relief (PEPFAR).

While that global effort is guided by a strategic plan with clear benchmarks for measuring progress, "America itself has no strategic plan to combat its own epidemic," said the report. The report Left Behind! Black America: A Neglected Priority in the Global AIDS Epidemic was produced by the Los Angeles–based Black AIDS Institute (BAI) with support from the Ford Foundation and the Elton John AIDS Foundation. Among the report's highlights:
• Close to 600,000 African Americans are living with HIV, and up to 30,000 more become infected each year.
• Adjusted for age, the death rate of blacks with HIV is nearly 2.5 times that of infected whites.
• Viewed as a country, black America's life expectancy would rank below that of 104 other nations.
Phil Wilson, BAI's CEO, said that the group supports PEPFAR. He added, however, "American policy makers behave as if AIDS exists elsewhere, as if the AIDS problem has been effectively solved" in the United States. BAI's report noted that the epidemic among US blacks shares 2 important characteristics with the epidemic in Africa: frequent heterosexual transmission and high rates of female HIV infection.

Dr Kevin Fenton, director of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, called the disparities staggering. "It is a crisis that needs a new look at prevention," he said.

Dr Helene Gayle, former director of the national center at the CDC and the current president of CARE, said the US government must do more to prevent sexually transmitted diseases, which can facilitate HIV infection; encourage more HIV testing, particularly to identify recent infections; and promote needle exchanges, which have been shown to reduce HIV transmission among injection drug users. [CDC HIV/Hepatitis/STD/TB Prevention News Update, Wednesday, July 30, 2008]

Senate Repeals HIV Travel Ban
AIDS advocates applauded the Senate's 80 to 16 vote on July 16 to repeal the long-standing ban on travel and immigration by non-US residents with HIV (Roehr B. Bay Area Reporter. July 17, 2008). The provision overturning the 20-year ban, sponsored by Sen John Kerry (D, Mass) and Sen Gordon Smith (R, Ore), was included as an amendment to the President's Emergency Plan for AIDS Relief. A bid by Sen Jeff Sessions (R, Ala) to reinstate the ban never materialized; he accepted a substitute amendment instead.

The Congressional Budget Office estimated that the cost of lifting the restrictions would amount to $83 million in additional medical costs over the next 10 years. To offset the cost, visa application fees were raised by $1 and immigration application fees by $2. "For those of us who have long dreamed of becoming Americans, and have been prevented by the 1993 law from ever being able to enter or leave the US without waivers or fear of humiliation, this is a massive burden lifted," said Andrew Sullivan, a conservative gay commentator.

"It is gratifying to know that my HIV-positive colleagues from other countries will finally be allowed to come to the United States to share their expertise," said Michael Saag, vice chair of the HIV Medical Association.

"We applaud the Senate for rejecting this unjust and sweeping policy that deems HIV-positive individuals inadmissible to the United States," said Joe Solmonese, president of the Human Rights Campaign, which lobbied to lift the ban.

The restrictions originated in 1987 and were codified by Congress in 1993. Immigration law excludes non-citizens with any "communicable disease of public health significance" from entering the United States. However, only HIV is explicitly named in the statute. [CDC HIV/Hepatitis/STD/TB Prevention News Update, Monday, July 21, 2008]

Gene Variation May Raise Risk of HIV
A genetic variation that protected people in sub-Saharan Africa from a now-extinct form of malaria may also have left their ancestors more vulnerable to HIV, according to a new study by US and UK researchers (Wade N. New York Times. July 17, 2008). The variation in a single unit of DNA could account for 11% of the HIV infections in Africa, they suggest.

Among those who carry this single nucleotide polymorphism (SNP), the surface of red blood cells lack the Duffy antigen receptor that receives a signal from the hormone CCL5, part of the immune system's regulatory system. About 10,000 years ago, it conferred protection to humans against the malarial parasite Plasmodium vivax. More than 90% of Africans and about 60% of African Americans lack the receptor.

The study involved Air Force members whose HIV infections have been studied for 25 years. African Americans who carried the SNP were 50% more likely to acquire HIV than African Americans who did not. However, the disease among carriers progressed more slowly, researchers noted. The finding "would be pretty exciting if it holds up," said David B. Goldstein, a geneticist who studies HIV at Duke University. "If the results are confirmed, it would mean that selection for resistance to malaria has created vulnerability to infection with HIV-1."

The exact mechanism promoting HIV infection is not certain, said Dr Sunil K. Ahuja, director of the Veteran Administration HIV/AIDS Center in San Antonio, Tex. How­ever, CCL5 is known to obstruct HIV's proliferation, and the red blood cells act like a sponge for CCL5, which may help prevent HIV infection.

The study results appeared in Cell Host & Microbe (He W, Neil S, Kulkarni H, et al. Duffy antigen receptor for chemokines mediates trans-infection of HIV-1 from red blood cells to target cells and affects HIV-AIDS susceptibility. Cell Host Microbe. 2008;4:52-62). [CDC HIV/Hep­a­titis/STD/TB Prevention News Update, Wednesday, July 23, 2008]

Meditation Slows AIDS Progression
A new study has found that meditation improved CD4+ T-cell counts in patients with AIDS (Fox M. Reuters. July 24, 2008). The researchers studied 67 HIV-positive adults from the Los Angeles area, most of whom reported highly stressful lives. "The average participant in the study was male, African American, homosexual, unemployed, and not on [antiretroviral] medication," they wrote. Approximately 30% of the volunteers were receiving antiretroviral therapy.

Forty-eight volunteers participated in some or all of a stress-lowering program called mindfulness meditation, defined as practicing an open and receptive awareness of the present moment and avoiding thinking of the past or worrying about the future. The meditation classes included 8 weekly 2-hour sessions, a daylong retreat, and daily home practice. CD4 counts were measured before and after the 2-month program. The more often the volunteers meditated, the higher their CD4 counts were. "This study provides the first indication that mindfulness meditation stress-management training can have a direct impact on slowing HIV disease progression," said study leader David Creswell of the University of California, Los Angeles. "Even when we controlled for ARV use, we still saw these effects."

It remains unclear how the stress-reducing effects of meditation work, said Creswell. Meditation may directly boost CD4+ T-cell levels or suppress HIV replication. "We know that stress has direct effects on viral load," Creswell said, adding, "One of the main side effects of this particular treatment was an increase in their quality of life.

"The mindfulness program is a group-based and low-cost treatment, and if this initial finding is replicated in larger samples, it's possible that such training can be used as a powerful complementary treatment for HIV disease, alongside medications," said Creswell.

The study results were published in Brain, Behavior, and Immunity (Creswell JD, Myers HF, Cole SW, Irwin MR. Mindfulness meditation training effects on CD4+ T lymphocytes in HIV-1 infected adults: a small randomized controlled trial. Brain Behav Immun. 2008:doi:10.1016/j.bbi.2008.07.004). [CDC HIV/Hepatitis/STD/TB Prevention News Update, Tuesday, July 29, 2008]