Universal HIV Screening Recommended by USPSTF

   The US Preventive Services Task Force (USPSTF) strongly recommends that clinicians screen all people aged 15 to 65 years for HIV infection, according to a draft recommendation statement posted online November 20. The statement also recommends HIV screening for all pregnant women, including those who present at the time of labor, and for younger adolescents and older adults who are at increased risk.

   "The draft recommendation reflects new evidence that demonstrates the benefits of both screening for and earlier treatment of HIV," task force member Douglas K. Owens, MD, said in a USPSTF news release. "Because HIV infection usually does not cause symptoms in the early stages, people need to be screened to learn if they are infected. People who are feeling well and learn they are infected with HIV can begin treatment earlier, reduce their chances of developing AIDS and live longer and healthier lives."

   Although US prevalence of HIV infection is nearly 1.2 million and annual incidence is about 50,000, nearly one quarter of those infected are unaware that they are HIV-positive. Since the first reports of AIDS in 1981, more than 1.1 million people have been diagnosed with AIDS and nearly 595,000 have died from it.

   Combined antiretroviral therapy (ART) has been shown to reduce the likelihood of HIV transmission, and earlier initiation of treatment lowers the risk for AIDS-related complications.

In issuing this recommendation, the task force hopes to improve and maintain the health of persons who are already infected with HIV, to delay the onset of AIDS, and to lower the risk for HIV transmission. The USPSTF is offering the public an opportunity to comment on this draft recommendation until December 17 and will consider all public comments when writing its final recommendation.

   Clinicians should screen adolescents and adults aged 15 to 65 years for HIV infection, as well as younger adolescents and older adults who are at increased risk (grade A recommendation).

Although evidence is insufficient to define optimal time intervals for HIV screening, the statement suggests that a reasonable strategy would be 1-time screening of adolescent and adult patients to identify those who are already HIV-positive and repeat screening of those known to be at risk for HIV infection, those who are actively engaged in high-risk behaviors, or those living in a high-prevalence setting.

   Clinicians should screen all pregnant women for HIV, including those of unknown HIV status who present in labor (grade A recommendation).

Evidence and Rationale

   The USPSTF updated their 2005 review on the benefits and harms of HIV screening in adolescents and adults by searching MEDLINE (2004 - June 2012) and the Cochrane Library (through the second quarter of 2012). Inclusion criteria were English-language randomized trials and observational studies comparing HIV screening approaches and reporting clinical outcomes, assessing the effect of initiating ART at different CD4 cell count thresholds and long-term harms, or reporting the effect of interventions on transmission risk.

   "Previous studies have shown that HIV screening is accurate, targeted screening misses a substantial proportion of cases, and treatments are effective in patients with advanced immunodeficiency," the USPSTF task force writes in its systematic review. "New evidence indicates that ART reduces risk for AIDS-defining events and death in persons with less advanced immunodeficiency and reduces sexual transmission of HIV."

   Evidence was convincing that standard and rapid HIV antibody tests are both highly accurate in diagnosing HIV infection.

   Evidence also was convincing that identifying and treating HIV infection in individuals with immunologically advanced disease (CD4 count <200 cells/mm 3) is associated with a substantially lower risk for progression to AIDS, AIDS-related events, and death.

   Evidence was adequate that starting ART earlier (at CD4 counts of 200 - 500 cells/mm 3) is associated with a lower risk for AIDS-related events or death.

   Finally, evidence was convincing that ART is associated with a markedly lower risk for transmission from HIV-positive persons to uninfected heterosexual partners and that identifying and treating HIV-positive pregnant women substantially lowers rates of mother-to-child transmission. Therefore, there are significant overall benefits of screening for HIV infection in adolescents, adults, and pregnant women.

   Although evidence is convincing that individual antiretroviral drugs, drug classes, and combinations are all associated with short-term adverse events, many are transient or self-limited, and there are often effective alternatives. Long-term use of certain antiretroviral drugs is linked to a small increase in risk for cardiovascular and other adverse events.

   "The overall harms of screening for and treatment of HIV infection in adolescents, adults, and pregnant women are small," the task force writes in its draft guidelines.

   "The USPSTF concludes that there is high certainty that the net benefit of screening for HIV infection in adolescents, adults, and pregnant women is substantial."