HIV SCREENING 

The US Preventive Services Task Force (USPSTF) recommends screening all adults and adolescents aged 15 to 65 years for HIV, according to updated guidelines published online April 29 in the Annals of Internal Medicine. The new recommendation also applies to all pregnant women who have not yet been screened, including those in labor.

The estimated US prevalence of HIV infection is 1.2 million, with an annual incidence of about 50,000. Nearly one quarter of persons with HIV infection are unaware of their positive status. More than 1.1 million have been diagnosed with AIDS since 1981, with nearly 595,000 deaths.

The USPSTF considers rapid screening tests that use blood or oral fluid specimens to be as accurate as conventional tests (repeatedly reactive immunoassay of serum specimen followed by confirmatory Western blot or immunofluorescent assay). However, clinicians should confirm positive rapid screening test results with conventional testing.

The USPSTF based their statement, which updates their 2005 HIV screening recommendation, on new evidence regarding the efficacy of treatments in HIV-infected persons with CD4 counts exceeding 0.200 × 10⁹ cells/L; the effect of screening, counseling, and antiretroviral therapy (ART) use on risky behaviors and risk for HIV transmission; and long-term cardiovascular harms of ART.

The reviewed evidence indicates that HIV screening is associated with very little risk for harm and with better clinical outcomes than no screening, including lower rates of progression to AIDS, AIDS-related events, and death. Starting ART in asymptomatic persons identified by screening also allows better outcomes.

The new evidence also suggests that HIV screening of pregnant women is linked to markedly lower rates of mother-to-child transmission and that targeted screening misses a substantial number of HIV-infected patients with undisclosed or unknown risk factors.

The 2005 guidelines recommended offering HIV screening to all adults and adolescents at increased risk for infection and discussing the benefits and harms of testing for patients with no risk factors. Unless pregnant women specifically refused testing, the USPSTF recommended HIV screening at the first prenatal visit.

Updated Recommendations

In their updated recommendation, the USPSTF now suggests that clinicians screen adolescents and adults aged 15 to 65 years for HIV infection, as well as younger adolescents and older adults at increased risk (grade A recommendation), and that they screen all pregnant women for HIV, including those who present in labor with unknown HIV status and no previous testing (grade A recommendation).

Women screened during pregnancy should be rescreened in subsequent pregnancies.

"The evidence is insufficient to determine optimum time intervals for HIV screening," the USPSTF writes. "One reasonable approach would be 1-time screening of adolescent and adult patients to identify persons who are already HIV-positive, with repeated screening of those who are known to be at risk for HIV infection, those who are actively engaged in risky behaviors, and those who live or receive medical care in a high-prevalence setting."

In an accompanying editorial, Moupali Das, MD, MPH, from the University of California, San Francisco, and Paul Volberding, MD, from the University of California, San Francisco, AIDS Research Institute, notes that these new USPSTF HIV screening guidelines now align more closely with CDC recommendations.

"Informing all infected persons of their status may well reduce ongoing transmission-risk behavior in [and] of itself, and if [ART] is also accepted and successful, further spread will be substantially reduced and perhaps even eliminated," the editorialists write. "Now, with an increasing consensus on population-wide screening, a growing belief in universal treatment, and the goal of near universal access to medical care under the Affordable Care Act, we may ultimately awaken from the nightmare of the HIV/AIDS epidemic."

The USPSTF published a draft version of these guidelines in November 2012.

The USPSTF is an independent, voluntary body supported by the Agency for Healthcare Research and Quality, as mandated by the US Congress. The authors and editorialists have disclosed no relevant financial relationships.

Ann Int Med. Published online April 29, 2013.