Global Epidemic of Human Immunodeficiency Virus (HIV)
Throughout its existence, the global HIV epidemic has dramatically changed since first recognized in 1981. The epidemic has become global, reaching every country and nearly all populations throughout the world. Spread of the disease has been particularly alarming in resource-limited countries, especially sub-Saharan Africa and southeast Asia, but continues to threaten other populations in eastern Europe, Latin America, and the Caribbean.
By the end of 2013, the reported statistics on the global burden of HIV were the following:
- 35 million adults and children were living with HIV/AIDS
- 2.1 million people, including 240,000 children, had been newly infected with HIV in that year
- 1.5 million people died of AIDS in that year
The overall prevalence of HIV appears to have stabilized, or increased in some countries, likely due to increased survival of infected people because of antiretroviral treatment. However, the 2013 incidence of new HIV infections represents a decline of 38 percent from 2001, when there were 3.4 million new infections.
Global Distribution of Human Immunodeficiency Virus (HIV)
Nearly three quarters of the world’s HIV-infected population are in sub-Saharan Africa. Countries in sub-Saharan Africa and the Caribbean have the highest national rates of adult HIV prevalence. Children bear a substantial proportion of the burden of HIV, both directly and indirectly. An estimated 3.3 million children are living with HIV/AIDS worldwide. Of the 260,000 infants and children infected with HIV in 2012, 70 percent were born in sub-Saharan Africa, 25 percent in Southeast Asia, and the remainder in Latin America and the Caribbean. Additionally, approximately 25 million children have been orphaned by the premature death of both parents due to AIDS, placing enormous responsibilities on their communities. As the epidemic continues to rise in Southeast Asia and Eastern Europe, these numbers are only likely to increase, unless more aggressive prevention campaigns and interventions programs intercede to slow the pace of the epidemic.
Worldwide, HIV/AIDS was one of the top ten causes of death in 2013, mainly driven by the mortality associated with HIV in sub-Saharan Africa, where it was the primary cause of death.
Human Immunodeficiency Virus (HIV) in Africa
Sub-Saharan Africa — Approximately 10 percent of the world’s population lives in sub-Saharan Africa, but the region is home to almost three-quarters of the world’s HIV-infected population. The overall HIV prevalence rate in this region is 4.7 percent, and some countries have a rate as 25 percent. Of the HIV-infected population within this region, 25 percent are in South Africa and 13 percent in Nigeria. Nevertheless, the largest epidemics in sub-Saharan Africa (South Africa, Nigeria, Ethiopia, Zambia, and Zimbabwe) have either stabilized or are showing signs of decline, mainly due to a decrease in the incidence of HIV and an increase in the number of infected people accessing treatment.
HIV infection in sub-Saharan Africa is mostly related to heterosexual transmission, and women account for 58 percent of the HIV-infected population in the region. The gender discrepancy is particularly evident among adolescents; the HIV prevalence among females aged 15 to 19 is five times higher than that among males of the same age. Much of heterosexual transmission occurs between established partners.
Human Immunodeficiency Virus (HIV) in Latin America and the Caribbean
Latin America and the Caribbean — After sub-Saharan Africa, the Caribbean has the second highest HIV prevalence rates in the world. Over 50 percent of the HIV-infected population in this region is in Haiti, although the highest HIV prevalence in the region is 3.2 percent, in the Bahamas. In Latin America, of the estimated 1.6 million HIV-infected individuals reported at the end of 2013, approximately three-quarters were in Brazil, Colombia, Mexico, and Venezuela. The regional HIV prevalence in the adult population overall was estimated to be 0.4 percent.
Human Immunodeficiency Virus (HIV) in Asia
Asia — The overall prevalence of HIV in Asia is low with only approximately 0.6 percent of the population having been diagnosed. However, this still results in a substantial burden of disease, given that the region accounts for half the world’s population. Of the estimated 4.8 million HIV-infected persons living in Asia, nearly half live in India. The estimates for India are based primarily on anonymous testing data from public clinics for prenatal care and for patients with other sexually transmitted infections (STIs). Approximately 85 percent of HIV transmission in India is thought to be through sexual contact. Barriers to control of the epidemiologic include the lack of social acceptance of condoms and laws making homosexuality illegal and punishable by imprisonment. In China, the government estimates that over one million people are infected with HIV, which represents an HIV prevalence of approximately 0.05 percent of the general population. Most cases are concentrated in five provinces: Guangdong, Guangxi, Xinjiang, Yunnan, and Henan, where residents became infected through contaminated equipment at a plasma donation center. A high HIV prevalence has also been found among MSM in other Asian countries including Cambodia (9 percent), Thailand (15 percent), and India (18 percent) . High prevalence among sex workers is also a major contributor to the spread of HIV in this region, where it exceeds 20 percent in certain urban centers throughout Asia (eg, Mumbai, Hanoi).
Human Immunodeficiency Virus (HIV) in the United States
United States — At the end of 2013, an estimated 1.2 million persons in the United States were living with HIV infection. In 2013, there were an estimated 47,352 new HIV diagnoses, or 15 diagnoses per 100,000 persons. In the mid-to-late 1990s, advances in HIV treatments slowed the progression of HIV infection to AIDS and led to dramatic decreases in deaths among persons with AIDS living in the United States. Certain racial and ethnic minorities in the United States have a disproportionately high rate of HIV infection. In 2012, the rate of new HIV diagnoses was higher than average among African-Americans, Latinos, and individuals of multiple races at approximately 56, 19, and 17 infections per 100,000 persons, respectively. Reported rates of HIV infection in non-Hispanic black females are 19 times higher than rates among non-Hispanic white females. Black men who have sex with men (MSM) have a threefold greater odds of being HIV-infected than MSM of other races.
Human Immunodeficiency Virus (HIV) in Europe
Europe — By the end of 2013, there were 1.7 million HIV infections in the World Health Organization (WHO) European Region, which includes Russia. In that year, there were 136,235 new HIV diagnoses reported (rate of 15.7 per 100,000 persons). This rate of new diagnoses represents an 80 percent increase compared with the rate in 2004. This increase is mainly due to increasingly high rates in eastern Europe, which was substantially higher than in western Europe (41.2 versus 2.2 new diagnoses per 100,000 persons, respectively). The highest rates were in Russia, Ukraine, and Estonia (55.6, 39.4, and 24.6 new diagnoses per 100,000 persons, respectively). The predominant mode of transmission for new diagnoses differed by region. In western and central Europe, sexual transmission among MSM was the most common route, followed by heterosexual transmission. In contrast, in eastern Europe, heterosexual contact accounted for the most new diagnoses, followed by injection drug use.
Treatment of Human Immunodeficiency Virus (HIV)
Marked advances in HIV antiretroviral therapy (ART) have resulted in significant changes in the survival rate and quality of life of HIV-infected individuals. Improving delivery of ART in resource-limited countries has been a primary focus of international efforts to combat the HIV epidemic. However, despite the advances in ART provision in such settings, a large proportion of HIV-infected patients still do not have access to or are otherwise not receiving ART. Additionally, a moderate failure rate and risk of adverse events leaves a portion of the population unable to receive adequate care.