WASHINGTON, United States (CMC) – The World Health Organization (WHO) said on Tuesday that while childhood immunisation in the Americas, including the Caribbean, showed encouraging signs of recovery last year, significant gaps remain.

According to the new data released by WHO and the United Nations Children’s Fund (UNICEF), over 1.4 million children did not receive a single dose of the diphtheria, tetanus and pertussis (DTP)-containing vaccine, marking an increase in so-called “zero-dose” children.

The findings are part of the 2024 WHO and UNICEF Estimates of National Immunization Coverage (WUENIC), which show that while global childhood vaccination coverage has largely stabilised, nearly 20 million children worldwide missed at least one DTP vaccine dose, including 14.3 million zero-dose children.

In the Americas, the number of zero-dose children rose by 186,000 compared to the previous year, reaching 1,465,000.

“The Americas has shown a firm commitment to protecting its child population, but the gaps in vaccination coverage remind us that more must be done,” said Dr Jarbas Barbosa, director of the Pan American Health Organization (PAHO), the regional office of WHO for the Americas.

“Vaccination remains one of the most effective tools to prevent diseases and save lives. We cannot allow any child to be left unprotected,” he added.

The WHO reported that immunisation coverage in the Americas improved for several key antigens, including measles, mumps, rubella (MMR), with coverage of the first dose increasing from 86 to 88 per cent and the second dose from 75 to 77 per cent.

Pneumococcal conjugate vaccine (PCV3) rose from 76 to 79 per cent, while hepatitis B at birth increased from 64 to 68 per cent, a key step toward hepatitis B elimination.

The WHO said that for the HPV vaccine, the Americas has the highest coverage globally, with 76 per cent of girls under 15 years of age receiving at least one dose. However, it said more effort is needed to reach the target of at least 90 per cent.

The WHO said that despite these gains, DTP1 coverage in the Americas declined slightly from 90 per cent in 2023 to 89 per cent in 2024, reversing a positive trend and contributing to the increase in zero-dose children.

DTP3 coverage remained steady at 86 per cent, but nine of 35 countries and territories reported coverage below 80 per cent, raising the risk of disease outbreaks. Additionally, three countries reported dropout rates above 10 per cent between the first and third DTP doses.

The WHO report said that these gaps reflect ongoing barriers in equitable access to immunization and retention, especially in marginalised and underserved communities.

Meanwhile, PAHO said it is working closely with countries to strengthen national immunisation programmes through Expanded Programme on Immunization (EPI) Maturity Assessments, completed for 12 countries in the last two-and-a-half years and already underway in Honduras, the Dominican Republic and Bolivia.

PAHO is also supporting countries to target children who missed vaccines during the COVID-19 pandemic, with expected coverage increases of one to four per cent in affected cohorts.

The United Nations (UN) health agency said that it is recommending priority actions for Caribbean and other countries in the Americas to include identifying and reaching zero-dose children with locally tailored strategies, strengthening follow-up systems to reduce dropout rates, as well as ensuring adequate vaccine supply and accessibility.

In addition, it is urging countries to continue training health workers and engaging communities to counter vaccine hesitancy.

“Member states must remain committed to strengthening immunisation strategies through joint efforts so that the region can reclaim its historic leadership in vaccination and protect the health of present and future generations,” said Dr Barbosa.