CDC FigureDespite recent improvements in getting people unknowingly living with the virus tested and linked to care, there is still a great deal of room for improvement with respect to keeping HIV-positive people retained in care, engaged in prevention counseling and on antiretroviral (ARV) treatment to maintain undetectable viral loads. This is the conclusion of a Morbidity and Mortality Weekly Report (MMWR) analysis titled “Vital Signs: HIV Prevention Through Care and Treatment—United States” and released November 29 by the U.S. Centers for Disease Control and Prevention (CDC) in advance of World AIDS Day, December 1.

Both good news and bad news can be found in the CDC’s analysis of available epidemiologic data. Encouragingly, nine of 10 people receiving routine HIV care in the U.S. have been prescribed ARV treatment and more than three-quarters have undetectable viral loads—findings that should bode well for personal and public health outcomes, notably decreases in the number of HIV-related deaths and fewer new cases of sexually transmitted HIV. Unfortunately, however, too few U.S. residents living with HIV are receiving the routine care they need. According to the CDC, only one in two HIV-positive people have been retained in necessary medical services, which partly accounts for the finding that only one in four U.S. residents living with HIV are being successfully treated with ARV drugs and have undetectable viral loads.   

This important disparity—the disconnect between what is possible for those receiving routine care and what is really going on in the overall population of U.S. residents living with HIV—uncovered in the CDC report underscores that a multi-faceted approach will be necessary to seriously curtain the ongoing epidemic in this country. In short, the CDC suggests, the positive outcomes for people living with HIV—longer disease-free survival and a reduced likelihood of ongoing transmission of the virus—require a continuum of care. It begins with testing to identify people infected with the virus, which must then lead to linkage to and, importantly, retention in continuous medical care for HIV, along with prevention counseling and other services aimed at reducing transmission and ensuring appropriately timely and consistent ARV therapy for viral suppression.

The CDC has long known that roughly 20 percent of people living with HIV don’t know they’re infected, ultimately preventing them from connecting with vital health care and prevention services. Though the CDC now recommends that all U.S. residents between the ages of 13 and 64 be tested for HIV at least once as part of regular medical care, there is also a need to ensure that those who do test positive for the virus are engaged in the entire spectrum of available care.

Yet the CDC analysis, which estimates the number of people living with HIV who receive selected services and who have undetectable viral loads, suggests this isn’t happening.

The CDC evaluated three surveillance datasets. The first included National HIV Surveillance System (NHSS) data, used to calculate the prevalence of HIV among U.S. adults between ages 18 and 64 at the end of 2008.

Data from the Behavioral Risk Factor Surveillance System (BRFSS)—a state-based, random-digit-dialed telephone survey of adults to collect information on preventive health practices and risk behaviors in the United States—were also employed to estimate percentages of state residents who reported testing for HIV during the 12 months preceding the interview.

Finally, Medical Monitoring Project (MMP) data—a collection of behavioral and clinical information from a nationally representative sample of adults receiving medical care for HIV in U.S. and Puerto Rican outpatient facilities—were used to document rates of prevention counseling, ARV prescriptions and undetectable viral loads within the 12 months leading up to the analysis.

As for estimates of people living with HIV entering, and being retained in, care, the CDC relied on previously published reports by other research teams.

An estimated 1.2 million people were living with HIV in the United States, of whom 80 percent had been diagnosed, according to earlier analyses conducted by the CDC. The prevalence rate for people between ages 18 and 64 with an HIV diagnosis averaged 417.5 per 100,000 U.S. residents, according to the NHSS analysis, with rates varying considerably by state—from 40.1 to 3,365.2 per 100,000 people.

In 2010, the BRFSS data showed, an estimated 9.6 percent of adults between the ages of 18 and 64 reported being tested for the virus within the 12 months leading up to their telephone survey. Recent HIV testing percentages, which ranged from 4.9 to an impressively high 29.8 percent, varied by state, with the best testing rate documented in states with the highest HIV prevalence rates.

Also encouraging, the CDC referenced published studies indicating that 77 percent of people diagnosed with HIV were linked to care within three to four months of diagnosis. What’s more, the MMP analysis found that of those retained in consistent care—people living with HIV who visit their providers on a regular basis—89 percent have been prescribed ARV therapy and 77 percent had undetectable viral loads at the time of the survey.

Where things start to fall apart is with the finding that roughly a third of those who initially find their way into care don’t receive regular follow-up—or they drop out of care completely. According to the CDC’s MMP analysis, only 51 percent of those living with HIV in the United States are being retained in medical care.

With the low rate of care retention, the viral load suppression rate also suffered. According to the CDC’s analysis, 328,475, or 35 percent, of the 941,950 people with confirmed HIV diagnosis—or 28 percent of all 1,178,350 people living with HIV—in the United States have undetectable viral loads. According to the CDC report, this low overall rate of suppressed HIV is "largely because even among those with diagnosed infection, only 51 percent are receiving regular HIV care."

The MMP analysis also determined that only 45 percent had received prevention counseling during the preceding year, with a notable age disparity. Only 36 percent of people 55 and older had received prevention counseling, compared with 73 percent of those between ages 18 and 24.

Whether this disparity is significant remains unclear. For example, it is possible that younger people were much more likely to receive prevention counseling because they were recently diagnosed, whereas those 55 and older may have been living with HIV much longer and wouldn’t have received counseling within the previous 12 months. 

By race/ethnicity, 54 percent of African Americans and 52 percent of Latinos received prevention counseling, compared with 29 percent of whites. Also of interest, prevention counseling was received by 50 percent of men who have sex with women and women who have sex with women, but only 39 percent of men who have sex with men.

“While we have known that viral suppression can be achieved with proper HIV treatment and care, today’s new Vital Signs data highlight the challenges our country faces in keeping HIV-positive Americans in the care they need to control the virus,” said CDC director Thomas R. Frieden, MD, MPH. “By improving testing, linkage to care and treatment services, we can help people living with HIV feel better and live longer, and can reduce the spread of HIV dramatically. This is not just an individual responsibility, but a responsibility for families, partners, communities and health care providers.”

Frieden’s remarks were echoed by Jonathan Mermin, MD, director of CDC Division of HIV/AIDS Prevention. “Closing the gaps in testing, access to care and treatment will all be essential to slowing the U.S. HIV epidemic,” he said. “HIV testing is the most important first step toward breaking the cycle of transmission. Combined with effective prevention services, linkage to care and ongoing effective treatment, testing provides a gateway to the most effective prevention tools at our disposal.”

Figure courtesy of the U.S. Centers for Disease Control and Prevention.