What are the factors that put adults most at risk of HIV?

Living in areas where people with HIV are not on effective treatment, having sex with someone of unknown HIV status and being female are some of the main factors that increase HIV risk, according to new analysis. 

What is the research about? 

The research examined the main risk factors linked to recent HIV infections among sexually active adults (ages 15-49) in 14 sub-Saharan African countries. 

The study is based on data from nationally representative population-based HIV surveys done between 2015 and 2019 in Cameroon, Cote d’Ivoire, Eswatini, Ethiopia, Kenya, Lesotho, Malawi, Namibia, Nigeria, Rwanda, Tanzania, Uganda, Zambia and Zimbabwe. A testing algorithm was used to distinguish between recent HIV infection (in past 12 months) and people who had been living with HIV for longer.  

Why is this research important? 

Identifying who is currently getting HIV and why is critical for knowing which groups are most at risk and the direction the HIV epidemic is going in. This can help to identify which groups most need tailored HIV prevention and testing programmes. 

What did they find out? 

The survey data included 16,830 people with HIV (plus 241,900 people without HIV). Among those with HIV, 1.6% were recently infected.  

Five groups had higher odds of recent infection.  

(1) Women 

Women were 1.82 times more likely to have recently got HIV than men. Women accounted for 65% of recent infections. Among young people (ages 15–24), young women accounted for 72% of recent infections.  

(2) People who are single, divorced, separated or widowed 

Having sex with a partner outside of marriage increased the chance of recent infection. But people who were divorced, separated or widowed had 3.58 times greater odds of recent infection than for those who were never married. 

(3) People with multiple recent sex partners 

People with more than one sexual partner in the previous 12 months were more likely to have recently got HIV. First having sex before the age of 18 also increased these odds. 

(4) People who recently had sex with someone with HIV or an unknown status 

In this category, most new infections occurred among people who had sex with someone of unknown HIV status rather than someone with a confirmed HIV-positive status. 

(5) People in areas with high HIV prevalence and/or where many people with HIV are virally unsuppressed 

People in east and southern African countries were more at risk of recent infection than people in west African countries where HIV prevalence is lower. This was true even after adjusting for the proportion of people with HIV that were virally unsuppressed (known as ‘community-level viremia’). In addition, people in areas with high levels of community-level viremia were more likely to have recently got HIV than people in communities with higher viral suppression rates. 

What does this mean for HIV services? 

In areas with high HIV prevalence, and/or where more people with HIV are virally unsuppressed, it will be an effective public health strategy to target people with HIV who are not yet diagnosed and on effective treatment. It is essential that such treatment as prevention initiatives are non-stigmatising and co-created with the groups that are being targeted. It also suggests the need to scale up PrEP and other HIV prevention programmes in these areas as a matter of priority. 

Communication and information campaigns that support and encourage people to use condoms or PrEP, especially if they are having sex with a partner or partners whose HIV status is unknown are also needed.  

There is a continued need for HIV prevention programmes that target women and girls. This includes encouraging male partners to test for HIV and get treatment which will further reduce infections among women.