Millions of children around the world, most of them in the poorest countries, missed some or all of their childhood vaccinations over the past two years because of a combination of conflicts, climate emergencies, misinformation campaigns, pandemic lockdowns and Covid vaccination efforts that diverted resources, according to a new analysis from Unicef, the United Nations agency that vaccinates half the world’s children, and the World Health Organization.
The report stated that this is the biggest backslide in routine vaccination in 30 years. It has led to conditions that could endanger the lives of millions upon millions of children, especially when combined with rising rates of malnutrition.
“This is an emergency for children’s health — we have to think about the immediate stakes, the number of children that are going to die because of this,” said Lily Caprani, head of advocacy for Unicef. “It’s not in a few years’ time; it’s quite soon.”
The percentage of children worldwide who had received three doses of the vaccine against diphtheria, tetanus and pertussis, known as DTP3 — which Unicef uses as a benchmark for immunization coverage — fell five points between 2019 and 2021, to 81 percent. The measles vaccination rate fell to 81 per cent, while polio coverage also dropped. To prevent disease transmission, a vaccination coverage rate of 94% is required for herd immunity.
This means that 25 million children did not receive basic protection against lethal diseases.
The number of what Unicef calls zero-dose children — those who have not received a single dose of the most basic vaccines — increased sharply during the pandemic, to 18 million from 13 million in 2019. This group represents half of all children who have died before the age of 5.
The agency had been hoping that after a sharp decline in 2020 that was driven by lockdowns, school closures and other Covid response measures, childhood vaccination coverage would rebound in 2021, said Dr. Niklas Danielsson, Unicef’s Nairobi-based senior immunization specialist.
The problem got worse. According to the report, DTP3 coverage and measles coverage have fallen to their lowest point since 2008.
Dr. Danielsson claimed that 2021’s rate of vaccination coverage is the same as 2008. “But since then, the birth cohorts have increased, which means that the number of children who do not complete vaccinations, or do not even start, is the largest in the last 30 years,” he said.
Many others working in child immunization had hoped for a recovery as health systems adjusted to the needs of the pandemic. Instead, misinformation about Covid vaccinations and greater distrust of governments over public-health measures led to routine immunization being stopped, he stated.
Gleichzeitig, the health systems of the poorest countries struggled to perform limited Covid vaccinations, diverting vital access to frozen food and health workers to administer shots to the arms.
Through the 1990s, and into the first decade of the 21st century, there was steady progress in child vaccination coverage. The rates of vaccinations began to slow down as the remaining children, including those living in war zones and nomadic communities, were more difficult to reach. However, before the pandemic there had been an increase in commitment and support from organizations such as the Bill and Melinda Gates Foundation and Gavi. This alliance is a global vaccine alliance that aims to reach those remaining children who are unable to receive zero-dose vaccines. Covid has taken away much of the attention and investment.
In the past two years, India and Nigeria, Indonesia, Ethiopia, Ethiopia, and the Philippines had the highest rates of vaccine-deficient children.
Brazil also made the top 10 list, which is a shocking shift for a country that was once known for its high levels of vaccination coverage. In 2021, only 26 percent of Brazilian infants received vaccines. This compares to the 13 percent who had in 2018.
“The work of 30 years has been lost overnight,” said Dr. Carla Domingues, an epidemiologist and former coordinator of Brazil’s national immunization program.
She said that vaccination became a politically charged topic in Brazil during the Covid epidemic. The federal government, led by President Jair Bolsonaro, downplayed the significance of the coronavirus even as Brazil had one of the world’s highest death rates and said he would not get his own 11-year-old vaccinated against the virus.
“For the first time, the federal government was not recommending a vaccine, and it created a whole environment of doubt that had never existed in Brazil, where vaccination was totally accepted,” Dr. Domingues said.
She said that anti-vaccination organizations in Brazil, which had not been able to purchase much, moved into Brazil during the pandemic and started spreading misinformation on social media in Portuguese.
All of this, Dr. Domingues stated, was occurring at a time when Brazilians were far removed from serious diseases they were being advised to immunize their children against. This led them to question the necessity.
“Parents don’t know the impact of measles, or of polio, so they start to pick and choose vaccinations,” she said. It is clear from data that the acceptance rate for the pneumonia vaccine has been higher than that of polio. “Parents are choosing not to do polio. They say, ‘It’s been 30 years with no polio, so do I need to do this?’”
And yet they have a clear sign of the risk, she said: A handful of measles cases were found earlier this year in São Paulo, six years after Brazil had reported eradicating the disease. “Measles is now circulating — that gives us a concrete example of what could happen with diphtheria, meningitis and so many other diseases,” she said.
Last year, 43% of Filipino infants were not vaccinated. This is due in part to Covid’s strict public health measures, which include lockdowns. “If you are not allowed to take your children out apart from certain hours of the day, if they can’t go to school, if living costs are increasing, going to a health enter to have your child vaccinated drops down on your priorities,” Dr. Danielsson said.
But the Philippines’ situation is also complicated by lingering mistrust of vaccination after a wide rollout of a dengue vaccine, called Dengvaxia, in 2016 that later proved to have caused more severe cases of the disease in some who had received it.
“The Dengvaxia story compounded the vaccine hesitancy, particularly among the school children,” said Dr. Anthony Leachon, a public health advocate who has advised the presidency on the Covid response. “That was the problem. We’re still dealing with it.”
Unicef’s Ms. Caprani said that to restore vaccine levels to the level they were, it would require extraordinary resources and dedication.
“It’s not going to be enough to just go back to business as usual and restore ordinary, routine immunization,” she said. “We’re going to need really concerted investment and catch-up campaigns, because there’s a growing cohort of millions of children who are completely unimmunized living in countries that have high levels of malnutrition and other stresses.”
For example, in Zimbabwe, one in ten children who are hospitalized with measles is now dying. (The average mortality rate is one in 100 in low income countries, and less than one in 1,000 for high-income countries.
Dr. Fabien diomande is a polio eradication specialist with the Task Force for Global Health. He worked for many years in polio campaigns in West Africa and Central Africa and believes that reversing the decline of childhood immunization will require new nimbleness as well innovation and resources.
“It’s like we’re in a new world — those emergencies are not going to disappear,” he said. “We will still have Covid. There will be climate crises. We have to learn how to work in the context of multiple public health emergencies.”
Brazil’s Dr. Domingues suggested that Covid vaccination efforts could be an example of how to catch-up. Brazil has high vaccination coverage due to its pop-up vaccination stations and availability of shots at night and weekends.
Ms. Caprani stated that, while Covid has rekindled interest in global health cooperation, investments in surveillance and other new technologies could distract from the essential intervention required to address the child immunization problem: the deployment of thousands community health workers.
“We aren’t going to solve this with poster campaigns or social media posts,” she said. “You need outreach by reliable, well-trained, properly compensated community health workers who are out there day in, day out, building trust — the kind of trust that means you listen to them about vaccines. And there simply aren’t enough of them.”
Jason GutierrezContributed reporting from Manila