The World Health Organization (WHO) and UNICEF have sounded the alarm on widening immunization gaps worldwide, warning that millions of children remain dangerously exposed to vaccine-preventable diseases despite modest progress.
New data released on Tuesday by the global health agencies revealed that nearly 20 million infants missed at least one dose of the diphtheria, tetanus, and pertussis (DTP)-containing vaccine in 2024 alone. Among them, 14.3 million were “zero-dose” children, meaning they did not receive even a single routine vaccine—a worrying increase of 1.4 million compared to 2019, the baseline year for tracking global vaccination progress.
While the figures are troubling, there were small signs of improvement. Approximately 171,000 more children received at least one vaccine dose in 2024 compared to 2023, and an additional one million completed the full three-dose DTP series. Health leaders say these gains reflect countries’ determination to reach children amid ongoing crises.
“It’s encouraging to see a continued increase in the number of children being vaccinated, although we still have a lot of work to do,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “Vaccines save lives, allowing individuals, families, communities, economies, and nations to flourish.”
However, Tedros cautioned that budget cuts, conflict, and widespread vaccine misinformation could erase decades of hard-won progress.
Conflict and crises fuel setbacks
The report highlights how conflict and humanitarian crises continue to hamper global immunization. Twenty-six fragile or conflict-affected countries house a quarter of the world’s infants yet account for half of all unvaccinated children globally. In these regions, the number of zero-dose children rose sharply from 3.6 million in 2019 to 5.4 million in 2024.
Overall, 131 out of 195 countries consistently achieved at least 90% coverage for the first DTP dose since 2019. However, there has been no significant growth in this high-performing group. Among countries below 90% in 2019, only 17 improved, while 47 either stagnated or regressed—including 22 nations that previously exceeded the 90% mark but have now fallen below it.
“A quarter of the world’s infants live in just 26 countries affected by fragility, conflict, or humanitarian crises, yet they account for half of all unvaccinated children globally,” the report stressed.
Mixed progress on other vaccines
The global push to expand vaccine access beyond DTP saw some notable gains. In 2024, 31% of eligible adolescent girls received at least one dose of the HPV vaccine, up significantly from 17% in 2019. This milestone was largely achieved in countries using a single-dose schedule, making rollout more efficient.
Meanwhile, measles coverage showed slight improvements, with 84% of children receiving their first dose and 76% the second dose. Despite reaching an estimated 2 million additional children last year, global coverage still falls short of the 95% needed to prevent outbreaks everywhere. The number of countries experiencing large-scale measles outbreaks nearly doubled—from 33 in 2022 to 60 in 2024.
Gavi-supported countries making strides
On a more positive note, Gavi, the Vaccine Alliance, reported improvements across 57 low-income countries it supports. These countries reduced the number of un- and under-vaccinated children by about 600,000 in 2024. However, rapid population growth, ongoing conflict, and fragile health systems continue to challenge equity and universal coverage.
“The good news is that we have managed to reach more children with life-saving vaccines,” said Catherine Russell, UNICEF Executive Director. “But millions of children remain without protection against preventable diseases, and that should worry us all.”
Dr. Sania Nishtar, CEO of Gavi, also underscored the need for continued investment: “Lower-income countries protected more children than ever before in 2024. Yet population growth, fragility, and conflict present major hurdles to achieving equity, leaving the most vulnerable children and communities at risk.”
Call to action
Experts urge governments and partners to act with urgency, prioritizing local solutions, fighting misinformation, and investing in stronger, more resilient health systems.
“We must act now with determination to overcome barriers like shrinking health budgets, fragile health systems, misinformation, and access issues due to conflict,” Russell stressed. “No child should die from a disease we know how to prevent.”