Global epidemiology of HIV infection
- Thomas C Quinn, MD
Thomas C Quinn, MD
- Professor of Medicine
- Johns Hopkins Medical Institute
The acquired immunodeficiency syndrome (AIDS) was first recognized among homosexual men in the United States in 1981 [1,2]. While initially limited, infection with the human immunodeficiency virus (HIV) has literally exploded over the past three decades to become the worst epidemic of the twentieth century. With more than 35 million fatalities, the AIDS epidemic now ranks alongside the influenza pandemic of the early 1900s and the Bubonic plague of the 14th century in terms of fatalities . The impact of this disease on human suffering, cultures, demographics, economics, and even politics has been felt in nearly every society across the globe.
The initial optimism that followed the discovery of HIV, the development of diagnostic assays to help monitor the epidemic, the prophylaxis of opportunistic infections, the identification of effective antiretroviral drugs, and the prevention of perinatal transmission, has been tempered by the stark reality and magnitude of the global HIV pandemic. The epidemic continues to spread relentlessly into new areas and to consolidate in many other locations. In some countries in sub-Saharan Africa, the AIDS epidemic had caused a dramatic decline on life expectancy that may only now be rebounding with access to antiretrovirals.
This topic reviews worldwide statistics on the global HIV epidemic, modes of transmission, and the introduction of antiretroviral therapy (ART) into resource-limited settings. Updated information on global statistics is available on the Joint United Nations Programme on HIV/AIDS (UNAIDS) and on the United States Centers for Disease Control and Prevention (CDC) websites: www.unaids.org and www.cdc.gov, respectively. The clinical impact of ART on morbidity and mortality and the prevention of HIV are discussed in detail elsewhere. (See "The impact of antiretroviral therapy on morbidity and mortality of HIV infection in resource-limited settings" and "HIV infection: Risk factors and prevention strategies" and "When to initiate antiretroviral therapy in HIV-infected patients", section on 'Benefits of antiretroviral therapy'.)
ORIGIN OF THE HIV EPIDEMIC
While AIDS was only recognized in 1981, molecular phylogenetic studies indicate that HIV was present in central Africa since the early 1900s, likely in localized populations . The current pandemic may have emerged from these populations in the mid-1900s with improved access to transport and other societal changes .
Zoonotic transmission — Molecular phylogenetic studies suggest that HIV evolved from a lentivirus, simian immunodeficiency virus (SIV), which has been found in some subspecies of monkeys from Bioko (an island off the East African coast) and some subspecies of chimpanzees in the Cameroon [6,7]. Researchers believe that all the SIV strains infecting primates across Africa diverged from a common ancestor between 32,000 and 78,000 years ago .
- Centers for Disease Control (CDC). Pneumocystis pneumonia--Los Angeles. MMWR Morb Mortal Wkly Rep 1981; 30:250.
- Centers for Disease Control (CDC). Kaposi's sarcoma and Pneumocystis pneumonia among homosexual men--New York City and California. MMWR Morb Mortal Wkly Rep 1981; 30:305.
- Centers for Disease Control and Prevention (CDC). The Global HIV/AIDS pandemic, 2006. MMWR Morb Mortal Wkly Rep 2006; 55:841.
- Worobey M, Gemmel M, Teuwen DE, et al. Direct evidence of extensive diversity of HIV-1 in Kinshasa by 1960. Nature 2008; 455:661.
- Faria NR, Rambaut A, Suchard MA, et al. HIV epidemiology. The early spread and epidemic ignition of HIV-1 in human populations. Science 2014; 346:56.
- Heeney JL, Dalgleish AG, Weiss RA. Origins of HIV and the evolution of resistance to AIDS. Science 2006; 313:462.
- Worobey M, Telfer P, Souquière S, et al. Island biogeography reveals the deep history of SIV. Science 2010; 329:1487.
- Gao F, Bailes E, Robertson DL, et al. Origin of HIV-1 in the chimpanzee Pan troglodytes troglodytes. Nature 1999; 397:436.
- Keele BF, Jones JH, Terio KA, et al. Increased mortality and AIDS-like immunopathology in wild chimpanzees infected with SIVcpz. Nature 2009; 460:515.
- Murphey-Corb M, Martin LN, Rangan SR, et al. Isolation of an HTLV-III-related retrovirus from macaques with simian AIDS and its possible origin in asymptomatic mangabeys. Nature 1986; 321:435.
- Kiwanuka N, Laeyendecker O, Robb M, et al. Effect of human immunodeficiency virus Type 1 (HIV-1) subtype on disease progression in persons from Rakai, Uganda, with incident HIV-1 infection. J Infect Dis 2008; 197:707.
- Kiwanuka N, Laeyendecker O, Quinn TC, et al. HIV-1 subtypes and differences in heterosexual HIV transmission among HIV-discordant couples in Rakai, Uganda. AIDS 2009; 23:2479.
- Baeten JM, Chohan B, Lavreys L, et al. HIV-1 subtype D infection is associated with faster disease progression than subtype A in spite of similar plasma HIV-1 loads. J Infect Dis 2007; 195:1177.
- Keele BF, Van Heuverswyn F, Li Y, et al. Chimpanzee reservoirs of pandemic and nonpandemic HIV-1. Science 2006; 313:523.
- Sharp PM, Hahn BH. Origins of HIV and the AIDS pandemic. Cold Spring Harb Perspect Med 2011; 1:a006841.
- Archer J, Robertson DL. Understanding the diversification of HIV-1 groups M and O. AIDS 2007; 21:1693.
- Hemelaar J, Gouws E, Ghys PD, et al. Global trends in molecular epidemiology of HIV-1 during 2000-2007. AIDS 2011; 25:679.
- Hemelaar J. The origin and diversity of the HIV-1 pandemic. Trends Mol Med 2012; 18:182.
- Plantier JC, Leoz M, Dickerson JE, et al. A new human immunodeficiency virus derived from gorillas. Nat Med 2009; 15:871.
- Vallari A, Holzmayer V, Harris B, et al. Confirmation of putative HIV-1 group P in Cameroon. J Virol 2011; 85:1403.
- UNAIDS. Global AIDS update, 2016. http://www.unaids.org/sites/default/files/media_asset/global-AIDS-update-2016_en.pdf.
- Joint United Nations Programme on HIV/AIDS. The Gap Report. September 2014 http://www.unaids.org/sites/default/files/media_asset/UNAIDS_Gap_report_en.pdf (Accessed on May 20, 2015).
- UNAIDS Report on the Global AIDS Epidemic, 2013. UNAIDS Geneva. http://www.unaids.org/en/resources/documents/2013/name,85053,en.asp (Accessed on December 09, 2013).
- GBD 2013 Mortality and Causes of Death Collaborators. Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet 2015; 385:117.
- Dunkle KL, Stephenson R, Karita E, et al. New heterosexually transmitted HIV infections in married or cohabiting couples in urban Zambia and Rwanda: an analysis of survey and clinical data. Lancet 2008; 371:2183.
- Baral S, Beyrer C, Muessig K, et al. Burden of HIV among female sex workers in low-income and middle-income countries: a systematic review and meta-analysis. Lancet Infect Dis 2012; 12:538.
- Smith AD, Tapsoba P, Peshu N, et al. Men who have sex with men and HIV/AIDS in sub-Saharan Africa. Lancet 2009; 374:416.
- Steinbrook R. HIV in India--a complex epidemic. N Engl J Med 2007; 356:1089.
- Gill B, Okie S. China and HIV - a window of opportunity. N Engl J Med 2007; 356:1801.
- Feng TJ, Liu XL, Cai YM, et al. Prevalence of syphilis and human immunodeficiency virus infections among men who have sex with men in Shenzhen, China: 2005 to 2007. Sex Transm Dis 2008; 35:1022.
- Centers for Disease Control and Prevention. HIV Surveillance Report, 2014; vol. 26. Published November 2015. http://www.cdc.gov/hiv/pdf/library/reports/surveillance/cdc-hiv-surveillance-report-us.pdf.
- Millett GA, Peterson JL, Flores SA, et al. Comparisons of disparities and risks of HIV infection in black and other men who have sex with men in Canada, UK, and USA: a meta-analysis. Lancet 2012; 380:341.
- Centers for Disease Control and Prevention (CDC). HIV infections attributed to male-to-male sexual contact - metropolitan statistical areas, United States and Puerto Rico, 2010. MMWR Morb Mortal Wkly Rep 2012; 61:962.
- European Centre for Disease Prevention and Control/WHO Regional Office for Europe. HIV/AIDS surveillance in Europe 2013. Stockholm: European Centre for Disease Prevention and Control; 2014. http://ecdc.europa.eu/en/publications/Publications/hiv-aids-surveillance-report-Europe-2013.pdf (Accessed on May 21, 2015).
- Kassanjee R, Pilcher CD, Busch MP, et al. Viral load criteria and threshold optimization to improve HIV incidence assay characteristics. AIDS 2016; 30:2361.
- Piot P. AIDS: from crisis management to sustained strategic response. Lancet 2006; 368:526.
- Quinn TC. Global burden of the HIV pandemic. Lancet 1996; 348:99.
- Beyrer C. HIV epidemiology update and transmission factors: risks and risk contexts--16th International AIDS Conference epidemiology plenary. Clin Infect Dis 2007; 44:981.
- Arasteh K, Des Jarlais DC. Injecting drug use, HIV, and what to do about it. Lancet 2008; 372:1709.
- Conrad C, Bradley HM, Broz D, et al. Community Outbreak of HIV Infection Linked to Injection Drug Use of Oxymorphone--Indiana, 2015. MMWR Morb Mortal Wkly Rep 2015; 64:443.
- Des Jarlais DC, Kerr T, Carrieri P, et al. HIV infection among persons who inject drugs: ending old epidemics and addressing new outbreaks. AIDS 2016; 30:815.
- Aspinall EJ, Nambiar D, Goldberg DJ, et al. Are needle and syringe programmes associated with a reduction in HIV transmission among people who inject drugs: a systematic review and meta-analysis. Int J Epidemiol 2014; 43:235.
- Mathers BM, Degenhardt L, Phillips B, et al. Global epidemiology of injecting drug use and HIV among people who inject drugs: a systematic review. Lancet 2008; 372:1733.
- Schwartländer B, Grubb I, Perriëns J. The 10-year struggle to provide antiretroviral treatment to people with HIV in the developing world. Lancet 2006; 368:541.
- Bendavid E, Holmes CB, Bhattacharya J, Miller G. HIV development assistance and adult mortality in Africa. JAMA 2012; 307:2060.
- Kim JY, Farmer P. AIDS in 2006--moving toward one world, one hope? N Engl J Med 2006; 355:645.
- Stringer JS, Zulu I, Levy J, et al. Rapid scale-up of antiretroviral therapy at primary care sites in Zambia: feasibility and early outcomes. JAMA 2006; 296:782.
- Badri M, Lawn SD, Wood R. Short-term risk of AIDS or death in people infected with HIV-1 before antiretroviral therapy in South Africa: a longitudinal study. Lancet 2006; 368:1254.
- Lawn SD, Myer L, Harling G, et al. Determinants of mortality and nondeath losses from an antiretroviral treatment service in South Africa: implications for program evaluation. Clin Infect Dis 2006; 43:770.
- Jaffar S, Amuron B, Foster S, et al. Rates of virological failure in patients treated in a home-based versus a facility-based HIV-care model in Jinja, southeast Uganda: a cluster-randomised equivalence trial. Lancet 2009; 374:2080.
- ORIGIN OF THE HIV EPIDEMIC
- Zoonotic transmission
- Molecular epidemiology of HIV
- WORLDWIDE STATISTICS
- General statistics
- Sub-Saharan Africa
- Latin America and the Caribbean
- United States
- Methods for establishing HIV incidence
- MODES OF TRANSMISSION DRIVING THE EPIDEMIC
- Sexual transmission
- Injection drug use
- Mother-to-child transmission
- RISK FACTORS
- ART AND HIV EPIDEMIOLOGY
- Impact of ART
- ART coverage
- Access to ART
- COINFECTIONS WITH HIV