HIV is most prevalent in southern Africa, where several countries have adult infection rates above 15%. Eswatini has the highest prevalence of any nation on earth, with 23.4% of adults aged 15 to 49 living with the virus. Sub-Saharan Africa as a whole remains the epicenter of the global epidemic, though significant hotspots exist in other regions, including the southern United States.
The Highest Prevalence Countries
The ten countries with the highest adult HIV prevalence are all in sub-Saharan Africa. Based on 2024 World Bank data, they rank as follows:
- Eswatini: 23.4%
- South Africa: 17.2%
- Lesotho: 17.1%
- Botswana: 15.7%
- Zimbabwe: 9.8%
- Namibia: 9.0%
- Malawi: 6.2%
- Tanzania: 3.5%
- Republic of the Congo: 3.2%
- Kenya: 3.0%
The top four countries, all clustered in southern Africa, have prevalence rates that dwarf the rest of the world. To put this in perspective, roughly one in four adults in Eswatini and one in six in South Africa and Lesotho are living with HIV. Even further down the list, countries like Malawi and Tanzania carry a burden many times higher than most nations outside the continent.
Why Southern Africa Is Hit So Hard
Several overlapping factors explain why this region carries such a disproportionate share of the global epidemic. Poverty plays a central role: transactional sex is consistently linked to high HIV acquisition risk, and economic instability limits access to prevention tools like condoms and pre-exposure prophylaxis. Labor migration, historically tied to mining and agriculture in southern Africa, has also driven transmission by separating partners for long stretches and creating conditions where concurrent sexual relationships are more common.
Gender-based violence and cultural norms that encourage relationships between older men and younger women further fuel the epidemic. Young women in southern Africa face HIV risk six times higher than young men of the same age, and in eastern Africa, that gap is threefold. Adolescent girls and young women across sub-Saharan Africa are twice as likely to be living with HIV as their male peers. Biologically, high rates of untreated sexually transmitted infections among male partners increase the chance of HIV transmission, and historically low rates of male circumcision in countries like South Africa (below 30%) remove a factor known to reduce female-to-male transmission by roughly 60%.
Who Is Most Affected Globally
Beyond geography, certain populations carry elevated risk regardless of where they live. Men who have sex with men are disproportionately represented in new HIV transmissions across Europe, Brazil, and the United States. In the U.S. specifically, new infections are attributed primarily to male-to-male sexual contact, followed by heterosexual transmission, and to a lesser extent injection drug use. Recent research suggests that a slowing of public health intervention programs may partly explain a resurgence of infections among men who have sex with men in higher-income countries.
Female sex workers face elevated prevalence in many parts of Africa and Asia, particularly where criminalization limits their ability to access testing, condoms, and treatment. People who inject drugs remain a key population as well, with shared needles creating efficient routes for transmission in parts of Eastern Europe, Central Asia, and Southeast Asia.
HIV Prevalence in the United States
Within the U.S., the epidemic concentrates heavily in the South. In 2022, the southern states accounted for nearly half (49%) of the estimated 31,800 new infections nationwide. However, when adjusted for population size, the Northeast actually has the highest rate of people living with HIV per capita. This distinction matters: the South leads in raw numbers because of its large population and sprawling geography, but densely populated northeastern cities also carry substantial per-capita burden.
Rural communities in the South face a particularly difficult combination of challenges. Fewer than 9% of federally funded HIV care providers operate in rural areas, despite those areas containing a substantial share of the population. People diagnosed in rural settings experience longer travel distances to reach specialized care, lower access to preventive medications, and weaker financial support networks. In contrast, urban centers like Atlanta offer concentrated HIV services, community-based programs, and faster linkage to care after diagnosis. Rural residents also tend to have lower incomes and educational attainment, both of which correlate with later diagnosis and poorer long-term health outcomes.
Treatment Progress in High-Burden Areas
Despite staggering prevalence numbers, many of the hardest-hit countries have made real progress in getting people diagnosed and on treatment. The global goal, set by UNAIDS, is for 95% of people with HIV to know their status, 95% of those to be on antiretroviral therapy, and 95% of those on therapy to have the virus fully suppressed in their blood. No country has fully reached all three targets, but some high-prevalence nations are closing in.
In Zambia, for example, population-based surveys found that about 85% of people aware of their HIV status were on antiretroviral therapy, and roughly 87% of those on treatment had achieved viral suppression, meaning the virus was undetectable at meaningful levels in their blood. Viral suppression matters enormously: a person with an undetectable viral load cannot transmit HIV sexually, and they can expect a near-normal lifespan. These numbers are encouraging, but they also highlight the remaining gap. In the highest-prevalence clusters of Zambia, where about 14% of adults are HIV-positive, one in seven people on treatment still had detectable virus, and a meaningful share of people living with HIV had not yet started treatment at all.
The challenge going forward is reaching the people who fall through the cracks: those in rural areas far from clinics, young men who are less likely to test, and marginalized populations who avoid healthcare systems due to stigma or criminalization.