According to the CDC, about 1.1 million people in the United States are living with HIV infection, 21% of whom are currently undiagnosed. In 2008, the CDC estimated that approximately 56,300 people were newly infected with HIV in 2006. Over half (53%) of these new infections occurred in gay and bisexual men. African-American men and women were also strongly affected; these groups were estimated to have an incidence rate seven times as high as the incidence rate among Caucasians. Since the mid-1990s, there have been substantial reductions in the number of deaths and AIDS diagnoses thanks largely to increased screening efforts and use of effective antiretroviral therapy. Despite these advances, the incidence of HIV and new diagnoses in the United States has remained stable.

Social, ethnic, and cultural population subgroups are increasingly affected by HIV. “When HIV was first identified, it was primarily occurring among gay men,” explains Kathleen E. Squires, MD. “More recently, we’ve seen a marked evolution in the groups of people being affected by HIV. The single largest affected group has been African Americans [Figure 1], especially those who are younger and living in urban areas or the rural South.” More than 50% of new HIV diagnoses reported each year are among African Americans. Other ethnic groups also bear a disproportionate disease burden. In 2002, HIV was the third leading cause of death among Hispanic men aged 35 to 44, and the fourth leading cause of death among Hispanic women in the same age group. The population of HIV-infected Asian and Pacific Islanders is also increasing in the United States.

Considering Sexual Orientation

The most common HIV transmission categories include male-to-male sexual contact, injection drug use, a combination of male-to-male sexual contact and injection drug use, and high-risk heterosexual contact (Figure 2). “Many people think of homosexual activity as the primary culprit in HIV’s continued persistence, but the role of high-risk heterosexual activity cannot be underestimated,” says Dr. Squires. “While homosexual contact continues to account for a substantial number of new HIV cases throughout the United States, incidence rates are rising sharply among those engaging in high-risk heterosexual contact. Clinicians are also seeing more women with HIV infection than ever before. Furthermore, there has been an intersection between classical sexually transmitted diseases (STDs)—syphilis, chlamydia, and gonorrhea—and HIV. Patients are more frequently being diagnosed with another STD in addition to HIV.”

Making Testing Routine

In response to the changing epidemiology of HIV in the United States, the CDC and other organizations have offered strategic frameworks to make HIV testing a routine part of medical care. Efforts have also been made to implement new models for diagnosing HIV in different healthcare settings, preventing new infections, and further decreasing perinatal HIV transmission. In 2006, the CDC released revised recommendations on HIV testing that advocated offering generalized and routine testing to anyone between the ages of 13 and 64. Routine retesting is also recommended for people with ongoing risk.

“The CDC’s recommendations are important because clinicians have historically had difficulty trying to identify all patients considered at increased risk for HIV infection,” says Dr. Squires. “Various healthcare settings are unfortunately missing opportunities to diagnose HIV. In today’s world, anybody who goes to STD clinics should, as a part of the armamentarium of tests they receive, be offered HIV testing. When we think of STDs, HIV doesn’t always come to mind as easily as syphilis, chlamydia, and gonorrhea. Similarly, patients who visit the emergency room and are sexually active should also be tested. Such testing will provide opportunities to catch the infection earlier and help link patients to care and treatment.”

Keeping Guidelines in Mind

In 2009, the Department of Health and Human Services updated its guidelines for the treatment of HIV for adults and adolescents. Dr. Squires says that one of the important changes in these guidelines is the need for patients to receive treatment for the infection earlier in the disease course. “For the past several years, physicians have waited to start therapy until patients have more advanced HIV infection. Research now shows that outcomes can improve if efforts are made to control the infection as early as possible. Earlier treatment can help stabilize immune systems and improve the body’s ability to remain free of secondary opportunistic infections. Physicians need to be proactive about making an HIV diagnosis regardless of race, ethnicity, gender, or sexual orientation because it has implications for public and personal health. Patients are most likely to transmit HIV in the very early stages of the infection; an earlier diagnosis may reduce further transmissions. Collectively, these actions may translate to HIV patients living longer with fewer quality of life concerns.”


Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. December 1, 2009;1-161. Available at

Squires KE. Gender differences in the diagnosis and treatment of HIV. Gend Med. 2007;4:294-307.

World Health Organization. Epidemiological fact sheets on HIV and AIDS, 2008 update. Available at: Accessed September 1, 2009.

Branson BM, Handsfield HH, Lampe MA, et al; Centers for Disease Control and Prevention (CDC). Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR Recomm Rep. 2006;55:1-17. Available at:

Kitahata MM, Gange SJ, Abraham AG, et al; NA-ACCORD Investigators. Effect of early versus deferred antiretroviral therapy for HIV on survival. N Engl J Med. 2009;360:1815-1826.