Pronounced socio-economic inequalities across multiple HIV indicators in 18 African countries

Image by rbairdpccam. Creative Commons licence.

The richest people in many African countries were five times more likely to use condoms than the poorest, while also displaying more positive attitudes towards people living with HIV, according to a recent multi-country study published in AIDS.

Sub-Saharan Africa accounts for two-thirds of all HIV infections globally. Socio-economic inequalities contribute towards gaps in meeting HIV testing, treatment and viral suppression targets in this region; these disparities have been highlighted by UNAIDS as requiring urgent attention. Dr Mohamed Hamidouche and colleagues from the National Conservatory of Arts and Crafts in Paris undertook research to investigate socio-economic inequalities for different HIV indicators in multiple sub-Saharan African countries.

The study

The researchers used data from Demographic and Health household sample surveys conducted in 18 sub-Saharan African countries (Burkina Faso, Cameroon, Côte d’Ivoire, the Democratic Republic of Congo, Ethiopia, Guinea, Kenya, Lesotho, Liberia, Malawi, Mali, Niger, Rwanda, Senegal, Sierra Leone, Tanzania, Zambia, and Zimbabwe) between 2010 and 2018. Notably, the country with the largest HIV epidemic – South Africa – was omitted from this analysis. Social, economic and health information was collected through face-to-face interviews using standardised surveys. This included estimates of household wealth, based on assets owned and the presence of facilities, such as sanitation.


voluntary male medical circumcision (VMMC)

The surgical removal of the foreskin of the penis (the retractable fold of tissue that covers the head of the penis) to reduce the risk of HIV infection in men.


The surgical removal of the foreskin of the penis (the retractable fold of tissue that covers the head of the penis) to reduce the risk of HIV infection in men.

mother-to-child transmission (MTCT)

Transmission of HIV from a mother to her unborn child in the womb or during birth, or to infants via breast milk. Also known as vertical transmission.


Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

virological suppression

Halting of the function or replication of a virus. In HIV, optimal viral suppression is measured as the reduction of viral load (HIV RNA) to undetectable levels and is the goal of antiretroviral therapy.

The surveys also collected HIV-specific information from respondents, including HIV-related knowledge, attitudes towards people living with HIV, number of sexual partners, condom use, circumcision (in seven east and southern African countries), recent HIV testing and testing during pregnancy. In certain instances, anonymous HIV testing was conducted as part of the surveys and HIV prevalence among youth aged 15 to 24 was used as a proxy for HIV incidence.

The researchers used two ways of measuring inequalities – the relative index of inequality (here, an index or RII of 2 would mean that the richest were twice as likely to report an outcome than the poorest in a country) and the slope of index inequality, an absolute measure of inequality (here, an index or SII of 0.2 would mean that the outcome measured was 20% higher among the richest than among the poorest).

Data were collected on 358,591 participants for the study period (66% women) in the 18 countries. Participation rates for the surveys were high, ranging from 90% to 100%.

HIV-specific indicators

HIV-related knowledge was lowest in west and central African countries – less than 20% in eight out of ten countries gave correct answers to all seven knowledge questions. Cameroon and Burkina Faso were exceptions, as 30% and 23% of those sampled demonstrated good knowledge of HIV transmission and prevention. In contrast, knowledge was higher in east and southern African countries (highest in Zimbabwe and Rwanda at 40% and 43% respectively). Similarly, less than 50% expressed positive attitudes towards people living with HIV in all but one of the west and central African countries, whereas over 70% did so in six of the eight east and southern African countries.

Most participants reported having not having multiple sexual partners in the past year across all countries; this was highest in Rwanda and Ethiopia (98%). However, reported condom use for last sexual activity was highest in Lesotho at 51%, falling to as low as 1% in Niger.

Over 20% in all East and Southern African countries had taken an HIV test in the past year, but this fell below 20% in nine out of ten West and Central African countries. Testing during pregnancy was reported at levels above 95% in most East and Southern African countries (it was lower in Ethiopia at 57%), but it was reported at less than 90% in West and Central Africa (ranging from 23% in Mali to 89% in Cameroon). Male circumcision was only measured in East and Southern Africa and ranged from 9% in Malawi to 85% in Rwanda.

Socio-economic inequalities in HIV indicators

There were significant differences in both relative and absolute inequalities in terms of HIV indicators, with the richest in society faring better on HIV-related knowledge, positive attitudes to people with HIV, condom use at last sex, recent HIV testing, testing during pregnancy, and male circumcision. Interestingly, the poorest reported lower levels of sexual partners and had lower rates of HIV infection. This lack of a socio-economic gradient in terms of HIV incidence could indicate a changing epidemic pattern, with higher risk moving from the wealthiest to the poorest over time.

In terms of relative inequalities, the highest difference was observed for condom use, with the richest being five times more likely to use condoms than the poorest (RII = 5.02; 95% confidence interval, CI, 2.79-9.05). Relative inequalities were significantly higher in West and Central Africa than in East and Southern Africa for HIV-related knowledge, positive attitudes, condom use, recent HIV testing and testing during pregnancy.

In terms of absolute inequalities, the largest gap between the richest and poorest was noted for positive attitudes towards people living with HIV, with a 32% difference (SII=0.32; 95% CI 0.26-0.39) – the richest were more likely to display positive or non-stigmatising attitudes. Absolute levels of inequalities were once again higher in West and Central Africa, especially for HIV testing during pregnancy and recent HIV testing.

Ethiopia had the highest levels of inequalities on both the relative and absolute measures. Most indicators (apart from condom use and circumcision) showed significant positive correlations between relative and absolute inequality metrics.

In terms of explaining the wealth-related inequalities noted for different regions, the authors provide a few reasons for the higher levels of inequalities in West and Central African countries. One is that the private healthcare sector is more prominent and thus user fees may be a barrier to poorer people accessing care. Additionally, HIV epidemics are smaller overall, leading to greater levels of inequality seen between the richest and poorest and reduced levels of donor funding for general population interventions in these countries.


“Large absolute and relative inequalities, overall, remain regarding lack of knowledge and stigmatizing attitudes toward people living with HIV, and this may undermine HIV prevention, care and treatment,” the authors conclude. “Concerning inequalities are observed in condom use, prevention of mother-to-child transmission, voluntary medical male circumcision and HIV testing, especially in West and Central African countries. This is of particular concern because these are interventions that can prevent new infections, directly for condom use and voluntary male medical circumcision, or when linked to care and treatment for prevention of mother-to-child transmission and HIV testing. Large inequalities in condom use may reflect difficulties to access condoms free of charge.”


Hamidouche M et al. Monitoring socioeconomic inequalities across HIV knowledge, attitudes, behaviours and prevention in 18 sub-Saharan African countries. AIDS, available online 21 Feb 2022.

Full image credit: Bamenda waterfall. Image by rbairdpccam. Available at under a Creative Commons licence CC BY-NC 2.0.