HIV Surveillance -- United States, 1981-2008

Editorial Note

Three decades after the first cases were reported in the United States, HIV infection is no longer inevitably fatal. Highly active antiretroviral therapy suppresses viral replication for decades, allowing patients to enjoy longer and healthier lives and making them less infectious to others.⁴ A recent study of 3,400 heterosexual couples in Africa found that use of antiretroviral therapy reduced HIV transmission risk by 92%.⁴ HIV-related mortality, perinatal transmission, and the number of new HIV diagnoses among injection drug users have plummeted.² Nucleic acid testing now can detect HIV as early as 9 days after infection, enhancing the safety of the blood and organ supply and providing opportunities for early detection and disease intervention, including partner notification.⁵ Preexposure prophylaxis and topical microbicides are promising biomedical interventions.⁶ The scientific progress in immunology, virology, pharmacology, and clinical management that led to these successes occurred at a faster pace than was imaginable in 1981, when the first cases of AIDS were identified.

HIV prevention efforts averted an estimated 350,000 HIV infections during 1991-2006 and saved $125 billion in medical care costs.⁷ However, despite these efforts and widespread knowledge of how to prevent HIV, CDC estimates that 50,000 persons are infected each year in the United States. More than half of the newly infected are MSM, and nearly half are black or African American.³ In addition, the findings in this report indicate that, of the estimated 1,178,350 living with HIV infection in the United States, 20.1% had undiagnosed HIV infections.

Surveillance data show that the proportion of HIV diagnoses occurring in MSM continues to grow. HIV incidence among MSM has increased steadily since the early 1990s.³ In 2009, MSM accounted for 57% of all persons and 75% of men with a diagnosis of HIV infection in the 40 states with longstanding, confidential, name-based HIV infection reporting.² Syphilis and gonorrhea are endemic among MSM; outbreaks or hyperendemic sexually transmitted infections have been reported from many communities where HIV infection also is prevalent, further increasing the risk for acquiring and transmitting HIV.⁸

Late diagnosis of HIV infection is common. Among persons with newly diagnosed HIV in 2008, 33% developed AIDS within 1 year of initial HIV diagnosis.² These persons likely were infected an average of 10 years before diagnosis. During this period, they missed opportunities to obtain medical care and to prevent unwitting transmission of HIV to others. Persons with a late diagnosis of HIV infection also are at greater risk for short-term mortality than those who receive an HIV diagnosis earlier in the course of infection. Initiation of care soon after diagnosis is recommended, yet a meta-analysis of 28 studies from multiple U.S. regions found that 28% of persons did not enter care within 4 months of HIV diagnosis.⁹ In addition, an estimated 41% of HIV-infected persons did not average at least two care visits in a year,⁹ as recommended by the U.S. Department of Health and Human Services.¹⁰

The findings in this report are subject to at least three limitations. First, reported HIV data used in the extended back-calculation method represent only a portion of persons in the United States who received a diagnosis of HIV infection; some areas with high incidence, including Maryland and DC, did not contribute HIV data. Availability of HIV data from these areas will increase accuracy of future prevalence estimates. Second, not all persons with HIV have received a diagnosis of HIV infection, and so, have not been reported to the public health surveillance system; data must be estimated for persons with undiagnosed HIV. Finally, the data have been adjusted statistically to account for delays in reporting new cases and deaths and for missing risk factor information, which might result in less stable results.²

The National HIV/AIDS Strategy¹ has three primary goals: 1) reduce HIV incidence, 2) increase access to care and improve health outcomes for persons living with HIV, and 3) reduce HIV-related health disparities. The strategy refocuses efforts toward intensified HIV prevention in communities where HIV infection is most prevalent, using a combination of effective strategies that seek to optimize entry into and retention in care and maintenance of viral suppression. CDC, in partnership with state and local health departments, will use surveillance data to evaluate the measurable outcomes of this strategy, including new diagnoses, early detection, entry into care, retention in care, and viral suppression, as well as progression to AIDS and death.

References

1. Office of National AIDS Policy. National HIV/AIDS strategy. Washington, DC: Office of National AIDS Policy; 2010. Accessed May 26, 2011.
2. CDC. Diagnoses of HIV infection and AIDS in the United States and dependent areas, 2009. HIV surveillance report, vol. 21. Atlanta, GA: US Department of Health and Human Services, CDC; 2010. Accessed May 26, 2011.
3. Hall HI, Song R, Rhodes P, et al. Estimation of HIV incidence in the United States. JAMA 2008;300:520-9.
4. Donnell D, Baeten JM, Kiarie J, et al. Heterosexual HIV-1 transmission after initiation of antiretroviral therapy: a prospective cohort analysis. Lancet 2010;375:2092-8.
5. Fiebig EW, Wright DJ, Rawal BD, et al. Dynamics of HIV viremia and antibody seroconversion in plasma donors: implications for diagnosis and staging of primary HIV infection. AIDS 2003;17:1871-9.
6. CDC. Interim guidance: preexposure prophylaxis for the prevention of HIV infection in men who have sex with men. MMWR 2011;60:65-8.
7. Farnham PG, Holtgrave DR, Sansom SL, Hall HI. Medical costs averted by HIV prevention efforts in the United States, 1991-2006. J Acquir Immune Defic Syndr 2010;54:565-7.
8. Handsfield HH. Stones unturned: missed opportunities in STD/HIV. Sex Trans Dis 2011;38:70-3.
9. Marks G, Gardner LI, Craw J, Crepaz N. Entry and retention in medical care among HIV-diagnosed persons: a meta-analysis. AIDS 2010;24:2665-78.
10. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Washington, DC: US Department of Health and Human Services; 2011. Accessed May 26, 2011.