Despite the rapid development and distribution of COVID-19 vaccines, the pandemic has led to a significant and concerning decline in routine childhood vaccinations. According to recent data from the World Health Organization (WHO) and the United Nations International Children’s Emergency Fund (UNICEF), the world has yet to recover from this “historic backslide” in immunization rates.
Dr. Katherine O’Brien, director of the Department of Immunization, Vaccines, and Biologicals at WHO, emphasized the urgency of addressing this issue. “The race is on to reach children who missed shots during the pandemic and to restore and strengthen immunization services beyond pre-pandemic levels,” she stated. This call to action highlights the critical need to rebuild global immunization infrastructure.
The 2023 immunization coverage report by WHO and UNICEF, which is the largest dataset on immunization trends globally, reveals that progress in returning to pre-pandemic immunization levels has stalled. The report analyzed estimates from 185 countries and used the third dose of the diphtheria, tetanus, and pertussis (DTP3) vaccine as a global marker for immunization coverage. In 2023, worldwide DTP3 coverage remained at 84%, the same as in 2022, but below the 86% recorded in 2019. This stagnation indicates a derailment from the Immunization Agenda 2030 goal of achieving 90% coverage for essential childhood and adolescent vaccines.
The stalled progress reflects ongoing challenges such as disruptions in healthcare services, logistical issues, vaccine hesitancy, and inequities in access to services. These barriers have left millions of children un- or under-immunized. Notably, the number of children who had not received a single dose of DTP3 increased by 600,000 from 2022 to 2023, bringing the total to 2.7 million more children without full immunization compared to pre-pandemic levels.
Dr. Ephrem T. Lemango, associate director for health and global chief of immunization at UNICEF, stressed the importance of accelerating efforts to meet these challenges. “Today’s release highlights that we are off track and need to accelerate efforts to meet this challenge,” he said.
Despite these overall challenges, there are positive signs in certain regions. The African region, for instance, made significant progress in overall coverage last year. Countries such as Bangladesh, Indonesia, Brazil, and Nigeria have also shown notable strides in recovering post-pandemic. In Africa, vaccine coverage in the first year of life increased despite a rising number of births, requiring more vaccinations to maintain the same coverage level.
The report also highlighted improvements in HPV vaccine coverage, with a 7% increase in coverage among girls, returning to near pre-pandemic levels. Studies have shown that the HPV vaccine can reduce cervical cancer rates in women by 87%. However, current coverage remains below the 90% target to eliminate cervical cancer as a public health problem.
A major focus remains on measles vaccination, as the disease remains a top contributor to preventing deaths globally. WHO estimates that global immunization efforts have saved 154 million lives over the past 50 years, with measles vaccination accounting for about 60% of this impact. However, the 2023 data revealed that measles coverage in countries with large or disruptive outbreaks post-pandemic is too low to control further outbreaks. Nearly 35 million children were left with no or only partial protection against measles.
Low vaccination coverage has led to measles outbreaks in 103 countries, affecting roughly three-quarters of the world’s infant population over the past five years. In the United States, for instance, the percentage of children vaccinated against measles, mumps, and rubella by age two fell to 92% in 2023, below the federal target of 95%.
Dr. Lemango emphasized the need for continued efforts and new partnerships to expand protection against infectious diseases like measles. The introduction of new and underutilized vaccines through initiatives like Gavi, the Vaccine Alliance, is seen as crucial in reducing the burden of these diseases.
The data also revealed that over half of unvaccinated children in 2023 lived in countries experiencing fragility, conflict, and vulnerability, which account for only 28% of new births worldwide. Countries like Sudan, Yemen, and Afghanistan have shown worrying declines in immunization performance since 2019.
In response to these challenges, WHO and UNICEF, along with partners such as Gavi and the Bill & Melinda Gates Foundation, launched The Big Catch Up initiative in April 2023. This effort aims to boost childhood immunizations and bridge the gaps between pre- and post-pandemic coverage.
Dr. Lemango remains optimistic about the future of immunization. “The future is likely to be a future where we’ll have many vaccines that are able to prevent preventable diseases,” he said. “Immunization stands as one of humanity’s greatest achievements.”
The global community must now work together to overcome the setbacks caused by the pandemic and ensure that every child has access to life-saving vaccines.
