5 eye-opening charts about vertical transmission of HIV around the world

Elaine Abrams, Professor of Epidemiology and Paediatrics at Columbia University, joined our annual conference remotely from New York to share an international perspective on vertical transmission. Here are some highlights. 

Overall, there are currently 38.4m people living with HIV globally, including 16 million women of child-bearing age. There were 1.5m new infections in 2021 and 650,000 deaths, with 58% of new infections in sub-Saharan Africa.

1. The number of children living with HIV is falling over time

Professor Abrams drew attention to this UNAIDS graphic, showing the number of children with HIV decreasing over time. In 2021, 82% of these children lived in sub-Saharan Africa. So this tells a very positive story, with fewer paediatric infections, more children ageing out and far fewer deaths. 

2. ART coverage among pregnant women has remained stagnant since 2014

This next chart shows antiretroviral coverage among pregnant women, again globally, was around 81% at its highest point in 2019. It grew steadily from 2010-2014 and has then plateaued since 2014. Meanwhile, the number of new paediatric infections has declined by about 52% since 2010. This shows that the progress in preventing vertical transmission has slowed. 

Professor Abrams highlighted the significant regional differences within this data: there’s close to 90% of ART coverage in Eastern and Southern Africa but only 60% in Western and Central Africa. And in 2021, 43% of all pregnant women everywhere who are living with HIV and not on ART lived in Western and Central Africa. 

Of 160,000 child infections, in 48% of cases, the mother did not receive ART during pregnancy or breastfeeding. For 22%, the mother was infected during pregnancy or breastfeeding and for another 22% the mother did not continue with treatment. 8% were on ART but were not virally suppressed.

3. More women know their status when entering antenatal care

According to iCap data from six African countries, the proportion of women entering antenatal care with known HIV status and on ART already has grown, from 45% in 2018 to 68% in 2022, reflecting the scale-up of ART in adult HIV programmes.

But again, there are significant regional variations. On the one hand, Botswana became the first country with a severe HIV epidemic to reach a vertical transmission rate of less than 5%. Whereas in Zambia, whilst almost all mothers receive ART in pregnancy there is poor retention in pregnancy and breastfeeding, resulting in a significant number of paediatric infections.

West and Central African ART programmes are much less mature, with lower ART coverage across adult populations. In Cameroon, only half were receiving ART before or during pregnancy. 

4. The highest rates of ‘newly testing positive’ are among young women

This group is also most at risk from unplanned pregnancy.

5. Early Infant diagnosis also remains stagnant

Only 62% of infants born to mothers with HIV had a diagnostic test by eight weeks of life in 2021, with the same geographic patterns: 25% in Western and Central Africa, and 71% in Eastern and Southern Africa. And there hasn’t been much improvement in recent years, we actually see it dropping in Western and Central Africa since 2019. 

It’s also noteworthy that there has been very limited uptake of point-of-care (POC) diagnostic testing for EID, despite the demonstrated clinical benefit. Whilst there have been some efforts to introduce point-of-care in many settings in Southern Africa but these were derailed by the Covid-19 pandemic. 

What responses have there been along the prevention of vertical HIV transmission cascade?

As well as laying the groundwork by sharing all of these insightful statistics, professor Abrams also shared some of the global efforts being made to bring down the numbers of vertical HIV transmissions further and address some of the barriers. These include: 

  • A New Global Alliance to End AIDS in Children by 2030, prioritising closing the treatment gap for pregnant and breastfeeding adolescent girls and women living with HIV. 
  • A rapid scale-up of TLD among adults in high HIV prevalence settings to improve health outcomes for all people, including children living with HIV. (TLD is a single pill and has the lowest risk of side effects.)
  • Increased efforts to retest HIV negative women late in pregnancy and during breastfeeding and looking to introduce PrEP in women who test negative in the ANC. 
  • High expectations for long-acting cabotegravir (CAB-LA) to prevent new infections in young women. Studies have shown superiority of results in CAB-LA when compared to the oral daily TDF/FTC. It’s received registration approval in several countries and registration has been submitted in multiple others. But we need more data on dosing and safety of CAB-LA in pregnancy and during breastfeeding. 

A huge thank you to Professor Abrams for sharing her perspective with us.