"A static epidemic"

Improved estimates still show public health efforts have had little success controlling the number of new HIV infections in the US.

Source: Alix Morris, IAVI Report, VAX 6 (5), May 2008.

I quote extensively from the opening of this important report from the International AIDS Vaccine Initiative:

Twenty-seven years after the US Centers for Disease Control and Prevention (CDC) published a report detailing a mysterious cluster of pneumonia cases that were later attributed to AIDS, the number of people living with HIV/AIDS in the United States has grown to an estimated 1.2 million, according to the most recent figures (see www.cdc.gov).

The ballooning HIV prevalence in the US can be attributed to the dramatically waning morbidity and mortality associated with HIV/AIDS. Since the days when an AIDS diagnosis was a virtual death sentence, HIV-related deaths in the US have declined significantly—plummeting by more than 70% following the discovery of highly-active antiretroviral therapy (HAART). Once the leading cause of death among Americans between the ages of 24 and 44, HIV is now usually a chronic condition when managed effectively with a combination of antiretrovirals (ARVs) that act on the virus, or its target cells, in different ways.

But what disconcerts public health researchers is the latest surveillance data, which illustrates a static epidemic. In the US, the HIV incidence, or number of new HIV infections that occur per year, has not changed much since 1994. Despite continued efforts to improve education and promote effective and available interventions like condoms, public health agencies have had little success in controlling the number of new HIV infections over the last 15 years.

This worrisome trend will be highlighted in a much-anticipated surveillance report from the CDC that incorporates comprehensive data from state registries and a more accurate method of identifying recently HIV-infected individuals. This new methodology, known as serological testing algorithm for recent HIV seroconversion (STARHS) employs a combination of the normal test or assay for HIV infection, which detects antibodies against the virus, and a less sensitive or “detuned” assay. If antibodies against HIV are detectable by the normal assay, but not by the less sensitive one, researchers using the STARHS methodology conclude that this individual was recently infected with HIV because their antibody responses are not as strong.

The new HIV incidence figures, based on the STARHS method, were submitted to an academic journal last year by the CDC to make sure the methodology, emerging data, and conclusions were scientifically rigorous, and the agency says the data is still undergoing review. The new incidence estimates are widely expected to be announced sometime this year, and they are likely to show that the number of new HIV infections for 2006 was significantly higher—perhaps by as much as 20,000 infections—than the annual estimate of 40,000 new HIV infections per year repeatedly cited by public health departments since 1994. Those familiar with the new methodology say the more accurate epidemiological data probably won’t be portrayed by the CDC as a major resurgence in overall incidence, but rather will dramatize how little progress has been made in preventing the spread of HIV among adults, particularly within at-risk populations. “Most likely it is just an upward adjustment and a more accurate estimate of what has been occurring in the last decade,” said Walt Senterfitt, a California epidemiologist involved with Community HIV/AIDS Mobilization Project (CHAMP), a national alliance of prevention activists.