The answer depends on where in the world you look. Globally, men account for the majority of new HIV infections, but in sub-Saharan Africa, women and girls make up 62% of new cases. In the United States, men represent the vast majority of new infections, with gay and bisexual men alone accounting for 71% of estimated new cases in 2022. The risk isn’t simply about biology or behavior in isolation. It’s shaped by anatomy, sexual dynamics, social power, and access to prevention.
The Global Picture by Gender
In 2024, an estimated 1.3 million people worldwide acquired HIV. Women and girls accounted for 45% of those new infections. That means men and boys made up the slight majority globally, but the split varies dramatically by region.
Outside sub-Saharan Africa, 73% of new HIV infections in 2023 occurred among men and boys. Within sub-Saharan Africa, the pattern reverses sharply: women and girls accounted for 62% of all new infections. Among young people aged 15 to 24 in that region, the disparity is even starker. An estimated 210,000 adolescent girls and young women acquired HIV in 2023, and 1.9 million young women in that age group were living with HIV compared to 1.2 million young men.
Why Women Are More Vulnerable Biologically
During heterosexual intercourse, the receptive partner faces a higher per-act risk of acquiring HIV. Seminal fluid carries large viral loads, and the vaginal and cervical lining has a large surface area of mucous membrane exposed during sex. This basic anatomy means that, act for act, transmission from an untreated male partner to a female partner is more likely than the reverse.
The vaginal microbiome also plays a role in how well prevention tools work. One study found that a topical prevention gel was three times more effective in women whose vaginal bacteria were dominated by healthy Lactobacillus species compared to women with other bacterial profiles. Certain bacteria can actually break down and inactivate the active drug before it can protect against HIV. This is one reason why some prevention methods have shown better results in men than in women.
Gay and Bisexual Men in the U.S.
In the United States, the group most disproportionately affected by HIV is gay and bisexual men. Of the roughly 31,800 estimated new HIV infections in 2022, about 22,500 (71%) were among men who have sex with men. Receptive anal intercourse carries a higher per-act transmission risk than vaginal intercourse because the rectal lining is thinner and more prone to small tears that allow the virus direct access to the bloodstream.
The numbers don’t reflect riskier individual behavior so much as the compounding effects of biology and social context. Stigma, homophobia, discrimination, poverty, and limited access to quality healthcare all drive these disparities. Men who fear discrimination may avoid testing or delay treatment, which keeps viral loads higher in the community and increases the chance of onward transmission.
Transgender Women Face the Highest Rates
Transgender women are approximately 13 times more likely to be living with HIV than other adults of reproductive age, according to the World Health Organization. This makes them one of the most affected populations worldwide. The reasons are layered: high rates of discrimination in healthcare settings, economic marginalization that can lead to survival sex work, social exclusion, and barriers to accessing prevention and treatment services.
Social and Economic Forces That Shape Risk
Biology only tells part of the story. For women and girls, especially in high-burden regions, social inequality is a primary driver of HIV risk. Women often have less power to negotiate condom use. Sexual violence, which remains widespread globally, directly increases transmission risk. For many young women, marriage itself is a risk factor, particularly in settings where older male partners are more likely to be living with undiagnosed HIV.
Economic dependence compounds the problem. Women with fewer financial resources have less ability to leave risky situations or access prevention tools. Women widowed by AIDS or living with HIV may face property disputes and limited legal recourse, deepening their vulnerability. And regardless of their own HIV status, women disproportionately shoulder the burden of caring for sick family members and orphaned children, which limits their own education and earning potential.
Gaps in Prevention Access
Pre-exposure prophylaxis (PrEP), a daily or injectable medication that prevents HIV, has been a game-changer for populations with high infection rates. But access is uneven. In the U.S., PrEP use among eligible heterosexually active adults was below 1% as of 2019, and only about a third of those who could benefit from it had even heard of it. Among those who were aware, women actually had slightly higher awareness rates (35%) than men (29%), yet almost none were using it.
This gap matters because heterosexual women in the U.S., particularly Black women in the South, face meaningful HIV risk but are often overlooked in prevention messaging that focuses on gay and bisexual men. Globally, expanding PrEP access for young women in sub-Saharan Africa has become a major public health priority, with newer long-acting injectable options helping to close the gap left by daily pills.
Risk Depends on Context, Not Just Gender
There is no single answer to which gender is “more at risk.” In sub-Saharan Africa, being a young woman is one of the strongest risk factors for HIV. In the U.S. and Europe, gay and bisexual men and transgender women bear the heaviest burden. Globally, men account for a slight majority of new infections, but women face unique biological vulnerabilities and social barriers that concentrate risk in specific populations and regions. The common thread across all groups is that structural factors like poverty, stigma, violence, and unequal access to healthcare amplify biological risk far beyond what anatomy alone would predict.