Immunization Coverage in 2023: Stalled Progress and Missed Targets  

The World Health Organization and UNICEF have released the much-awaited 2023 immunization coverage estimates that show stagnating progress and highlight that coverage is still trailing pre-pandemic levels, which were already flattening prior to 2019. The report shows that Immunization Agenda 2030 (IA2030) targets are more elusive than before and is a warning that “business as usual” is grossly insufficient.

 Number of zero-dose children continues to rise

14.5 million children born in 2023 were unvaccinated – 600,000 more than in 2022, highlighting deepening inequities and continued difficulties in reaching the most vulnerable children and communities. All these zero-dose children will remain at high risk of dying from preventable diseases such as pneumonia and diarrhea, which account for nearly a quarter of child deaths globally. Their unvaccinated status also places them at the epicenter of highly infectious disease outbreaks such as measles, vaccine-derived polio, diphtheria, cholera, and others, which means we should expect no reprieve in the recurrent disease outbreaks we are now seeing across the globe.

While reaching zero-dose children has been a top priority for many organizations, it is becoming clear that what is being done is not working. Identifying and reaching zero-dose children requires moving away from globally prescribed solutions and transferring power and resources to local levels for sustained change. Without this pivotal shift, progress will remain elusive.

The number of under-vaccinated children is too high

Important as it is to reach the 14.5 million zero-dose children with their first DTP (diphtheria, tetanus, and pertussis) shot, it is no less vital to ensure that these children receive all vaccines and are fully immunized. In 2023, 13 percent of children residing in low-income countries who received their first dose of DTP dropped out before receiving their first dose of the measles vaccine. Partial protection is not good enough and children must be fully armored against all vaccine-preventable diseases.

Substantial investment is urgently required to address current barriers — such as unavailability of vaccines, provider attitudes, long waiting hours, lack of seating facilities, distance and costs involved in travelling to health facilities, disproportionate caregiving burden on women, and inconvenient session timings — as well as emerging obstacles stemming from factors like climate change, displacement, and anti-vaccine propaganda. As previously stated, adopting a community-centric approach will be key to understanding and surmounting the reasons why so many children are dropping out before they are fully immunized.

IA2030 targets increasingly out of reach

While the overall breadth of protection provided by 13 vaccines improved to 73% — a two-percentage point increase since 2019 — coverage for individual vaccines remains well below the 90% target set in the IA2030 agenda. Though diarrhea and pneumonia remain major causes of child deaths, coverage rates for the rotavirus and pneumococcal conjugate vaccines stand at 55% and 65%, respectively. Achieving 90% coverage for all vaccines will require rapid introductions in countries that have yet to roll out some of the most essential vaccines, as well as intentional strategies to scale up coverage. Faced with fiscal constraints, competing demands, and global recommendations to introduce additional new vaccines — beyond the 13 included in IA 2030 — many countries could struggle to gather the momentum needed to reach targets that are a mere six years away.

Cautious optimism around HPV vaccination

One bright note: global HPV vaccination rates increased substantially in 2023 with 27% of 15-year-old girls receiving a first dose. This growth was due in large part to introductions in Bangladesh, Indonesia, and Nigeria, and shows the progress that can be made with targeted focus. However, coverage in countries with established HPV vaccination programs is still trending lower than 2019 levels and remains far below the 90% target (65% in high-income countries and 59% in low and middle-income countries), underscoring the myriad challenges related to sustaining high coverage. Linking HPV vaccination to cervical cancer elimination and integrating primary and secondary prevention will be key to dispelling misperceptions and boosting community confidence in preventative tools, including vaccines.

Looking ahead

Overall, 2023 WUENIC estimates are a reminder that time alone will not right the ship of lagging immunization levels post-pandemic. Rather, we will need to deepen our understanding of how old and familiar challenges are intersecting with new and emerging issues and drastically revamp a global immunization toolbox that is blunt and seems increasingly outdated.