After recovering partly in 2022, global childhood vaccination rates stagnated in 2023, remaining below pre-COVID-19 pandemic levels. These data are from a new joint report by the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF).
Contrary to the global trend, Brazil showed improvements in most indicators. The country moved off the list of the 20 countries with the most unvaccinated children in the world. In 2021, Brazil ranked seventh on this list.
The newly published material represents the largest and most comprehensive global database of immunization estimates, providing information on trends in vaccination against 14 diseases.
In 2023, globally, the number of children who received three doses of the vaccine against diphtheria, tetanus, and pertussis (DTP) — the trivalent vaccine, which is considered a global marker for childhood immunization — remained stagnant at 84% (108 million), which is the same percentage as in 2022.
On the other hand, the number of so-called "zero-dose" children, who have not received any dose of the vaccine, increased from 13.9 million in 2022 to 14.5 million in 2023.
In Brazil, however, the number of children who had not received any dose decreased from 418,000 in 2022 to 103,000 in 2023. The coverage for the first dose of the vaccine, which is administered in the country by the National Immunization Program as the pentavalent vaccine, jumped from 84% in 2022 to 96% last year.
Brazil's strong performance, with the largest child population in Latin America, helped boost results in the Americas, which is the only WHO region on a positive trajectory to achieve the targeted goal of reducing "zero-dose" DTP children by 2030.
The recovery of Brazil's vaccination coverage was praised during the report's press conference.
"There has been a significant improvement in Brazil," said Dr Katherine O'Brien, director of immunization, vaccines, and biological products at WHO. "The country performed very well in its recovery between 2022 and 2023, and this is a major reason why the Americas' data looks better.
"Of course, Brazil is such a large country and has such a strong immunization program that seeing this improvement is really important," she added.
Health Minister NÃsia Trindade welcomed the results, recalling that "since 2016, Brazil had been facing increasing drops in vaccination coverage for various vaccines on the childhood immunization schedule.
"All of this was made possible through the dedication and work of healthcare professionals and state and municipal managers. Our thanks to all those who mobilized, who brought children to update their vaccination records, and who trusted in the Unified Health System."
Despite calls from WHO and UNICEF to expand vaccination coverage worldwide, the number of immunized children remains below prepandemic levels.
In 2023, there were 2.7 million more unvaccinated or underimmunized children compared with 2019, which was the last year before the COVID-19 health emergency.
Countries' health systems are vulnerable to various factors that hinder adequate childhood immunization, including conflicts, lack of investment, and disease outbreaks.
"Among children who remain unvaccinated or undervaccinated, approximately 10.8 million infants (51%) live in countries with institutional and social fragility or conflict-affected countries. Children residing in such challenging circumstances are the most vulnerable to disease outbreaks and require urgent attention and support," according to the report.
Because of its high transmissibility, measles is considered an indicator of vaccination gaps in populations. The new data indicate that coverage of the vaccine against the disease has stagnated.
To prevent outbreaks, avoid deaths, and achieve disease elimination goals, 95% coverage is necessary. However, in 2023, only 83% of the world's children received their first dose of the measles vaccine. The number of those who received the second dose increased slightly from the previous year to 74%.
In the past 5 years, measles has spread in various parts of the world. Outbreaks of the disease occurred in 103 countries, and according to the report, low immunization rates (80% or less) were a significant factor in the contagions. In contrast, 91 nations with high vaccine coverage did not experience outbreaks.
"This is a solvable problem. The measles vaccine is inexpensive and can be administered even in the most challenging places," said WHO Director-General Tedros Adhanom Ghebreyesus, PhD, who reiterated the organization's commitment to "support countries in closing these gaps and protecting the most vulnerable children as quickly as possible."
The new report contained positive data for some vaccines, highlighting those against human papillomavirus (HPV), meningitis, pneumococcal disease, polio, and rotavirus.
Globally, the proportion of teenage girls who received at least one dose of the HPV vaccine, which protects against cervical cancer, increased from 20% in 2022 to 27% in 2023.
Among the factors contributing to the outcome is the use of a single-dose schedule for the HPV vaccine, in addition to the strong distribution of the vaccine in Gavi-supported countries like Bangladesh, Indonesia, and Nigeria.
This story was translated from the Medscape Portuguese edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.
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