July 18, 2017
Worldwide, 12.9 million infants — close to 1 in 10 — did not receive any vaccinations in 2016, according to the latest immunization data from the World Health Organization (WHO) and United Nations Children's Fund (UNICEF).
"Most of the children that remain un-immunized are the same ones missed by health systems, " Jean-Marie Okwo-Bele, MD, MPH, WHO director of immunization, vaccines and biologicals, said in a joint WHO/UNICEF news release.
"These children most likely have also not received any of the other basic health services. If we are to raise the bar on global immunization coverage, health services must reach the unreached. Every contact with the health system must be seen as an opportunity to immunize, " said Dr Okwo-Bele.
In addition to the 12.9 million unimmunized infants in 2016, an estimated 6.6 million infants who did receive their first dose of diphtheria-tetanus-pertussis (DTP)–containing vaccine did not complete the full three-dose DTP immunization series (DTP3) in 2016, WHO and UNICEF report.
Since 2010, the percentage of children who did get the full course of routine immunizations has stalled at 86% (116.5 million infants), with no marked changes in any countries or regions in the past year. This falls short of the global immunization coverage target of 90%, they point out.
According to the new data, 130 of the 194 WHO member states (67%) have met and sustained at least 90% coverage for DTP3 at the national level, a target set out in the Global Vaccine Action Plan.
However, an estimated 10 million additional infants need to be vaccinated in 64 countries, if all countries are to achieve at least 90% coverage. Of these children, 7.3 million live in fragile or humanitarian settings, including countries affected by conflict. Four million of these children live in just three countries — Afghanistan, Nigeria, and Pakistan — where access to routine immunization services is critical to achieving and sustaining polio eradication, the WHO and UNICEF note.
Eight countries had less than 50% coverage with DTP3 in 2016, including Central African Republic, Chad, Equatorial Guinea, Nigeria, Somalia, South Sudan, Syrian Arab Republic, and Ukraine.
Worldwide, 85% of children have received the first dose of measles vaccine by their first birthday through routine health services, and 64% have received a second dose. Nevertheless, coverage levels remain far short of those required to prevent measles outbreaks, stop preventable deaths, and achieve regional measles elimination goals, the agencies say.
They also report that 152 countries now use rubella vaccines, and global coverage rose from 35% in 2010 to 47% in 2016, which they see as a "big step " toward reducing the occurrence of congenital rubella syndrome.
However, global coverage of more recently recommended vaccines has yet to reach 50%. These include vaccines against rotavirus and pneumonia. "Vaccination against both these diseases has the potential to substantially reduce deaths of children under 5 years of age, a target of the Sustainable Development Goals, " WHO and UNICEF note in the news release. Yet many middle-income countries are lagging behind in the introduction of these newer and more expensive vaccines.
For the first time, WHO and UNICEF have collected disaggregated data on immunization coverage at the subnational level. Of 194 reporting countries, 125 reported on subnational coverage, covering nearly 20,000 districts and roughly two thirds of the global infant population. "These data will help shed more light on geographical disparities in access to vaccines, " the agencies say.
A separate report from WHO, titled "State of Inequality: Childhood Immunization," highlights inequalities in childhood immunization coverage in low- and middle-income countries over the past decade. It shows that global improvements have been realized, with variable patterns of change across countries, and that there is generally less inequality now than 10 years ago.
A 2010 UNICEF study showed that an equity-focused approach to child survival and development is the most practical and cost-effective way to meet health Millennium Development Goals for children.
"Immunization is one of the most pro-equity interventions around. Bringing life-saving vaccines to the poorest communities, women and children must be considered a top priority in all contexts, " Robin Nandy, MBBS, MPH, head of immunizations at UNICEF, said in the release.
An updated WHO fact sheet notes that immunization currently prevents between 2 and 3 million deaths annually, from diphtheria, tetanus, whooping cough, and measles. An additional 1.5 million deaths could be avoided if global vaccination coverage improves. Yet, an estimated 19.5 million infants worldwide are still missing out on basic vaccines.