Ángel Hernández Merino
Pediatrician and collaborator of the Advisory Committee on Vaccines, the Spanish Association of Pediatrics and the Spanish Association of Primary Care Pediatrics
The data provided by WHO and UNICEF are highly valuable for several reasons. Firstly, because they are new data for a comprehensive historical series, with a reliable methodology that has remained stable over time. Secondly, because they paint an accurate picture of the situation regarding childhood immunisation and also accurately identify weaknesses and challenges to be addressed.
A quick conclusion could be that in 2024 there has been an improvement in some of the key indicators compared to 2023, but this improvement is slight and insufficient, as pre-pandemic status has not been restored and it is estimated that if the current pace continues, the targets set for 2030 will not be achieved (such as halving the number of children with zero doses compared to 2019 and achieving 90% global coverage for DTP (3 doses), pneumococcal conjugate (3 doses) and measles (2 doses) vaccines throughout life).
To highlight some positive aspects highlighted in this WHO/UNICEF publication, the most notable improvements have been observed in coverage for: the inactivated polio vaccine in countries with outbreaks of polio caused by vaccine-derived polioviruses; the pneumococcal conjugate vaccine; rotavirus vaccination; and human papillomavirus vaccination. On the other hand, there is still a long way to go for these vaccinations in the countries that need them most.
Another important aspect is the role of Gavi [the Vaccine Alliance, an international public-private partnership], which currently reaches 57 countries. A new indicator shown in this WHO/UNICEF study is the Breadth of Protection, which combines the coverage of 11 priority vaccinations into a single value and shows that countries under Gavi's protection, as a whole, achieve similar values to those of all other countries outside Gavi's scope. The data also show the difficulties faced by countries that leave Gavi's umbrella in the years following their departure.
As various studies have repeatedly pointed out for many years, inequalities persist and are overwhelming.
And they could get worse in the coming years: Africa is the only WHO region that, even today, continues to experience continuous increases in the annual birth cohort; every year for as long as this trend continues, more children will need to be vaccinated. This links to the difficulties and challenges that will need to be addressed in the coming years if we are to get closer to the 2030 targets.
Strengthening vaccination in countries with a certain degree of social and economic stability in order to at least maintain (and ideally improve) current coverage levels (as is happening with measles) requires explicit, broad and sustained social, academic, economic and political commitment. However, the greatest challenges come from the need to achieve widespread and equitable vaccination in countries suffering from mass displacement due to political instability, armed conflict, economic uncertainty and climate crises. The effects of misinformation and vaccine hesitancy threaten all countries, whether highly developed or less so. In short, as we know, stable political and financial commitment over time is needed to maintain a primary care system that brings equity to health programmes, including immunisation.
The need for stable funding affects different countries around the world in different ways. Those with greater capacity will have to contribute more, as they have done for decades, albeit with enormous difficulties. Unfortunately, the new US administration has decided to go ahead with plans to drastically cut its contribution to global health programmes, such as vaccinations. This will have a huge impact, as the US has been the largest donor to these programmes (and this must be recognised), and its withdrawal from the WHO, Gavi and other entities will have to be made up by the rest of the international community until rationality returns to the US.
The data published by the WHO/UNICEF are not far from those shown by another recent study, carried out using a different methodology. With an extra dose of optimism, we could highlight the need for the international community to assume its shared responsibility to improve child health protection equitably around the world, confident that this can be achieved with tools such as vaccinations, which have already brought about extraordinary achievements such as the eradication of smallpox and the drastic reduction of terrible diseases such as polio, diphtheria and others.