Millions of children around the world, most of them in the poorest countries, missed some or all of their childhood vaccinations in the past two years due to a combination of conflict, weather emergencies, misinformation campaigns, pandemic lockdowns and vaccination efforts. against covid that diverted resources. , according to a new analysis by Unicef, the United Nations agency that vaccinates half of the world’s children, and the World Health Organization.
It’s the biggest setback in routine immunization in 30 years, according to the report. Combined with rapidly rising rates of malnutrition, it has created conditions that could threaten the lives of millions of young children.
“This is an emergency for children’s health: we have to think about what is at stake immediately, the number of children who are going to die from this,” said Lily Caprani, UNICEF’s head of advocacy. “It is not in a few years; it’s pretty early.
The percentage of children worldwide who had received three doses of the diphtheria, tetanus and pertussis vaccine, known as DTP3, which Unicef uses as a benchmark for immunization coverage, fell five points between 2019 and 2021, at 81 percent. Measles vaccination rates also fell to 81 percent, and polio coverage also dropped significantly. A vaccination coverage rate of 94 percent is necessary for herd immunity, to break the chain of transmission of a disease.
This translates to 25 million children who did not receive a basic intervention to protect against deadly diseases.
The number of what Unicef calls zero-dose children (those who have not received a single dose of the most basic vaccines) has risen sharply during the pandemic, from 13 million in 2019 to 18 million. This group includes half of all children who die before 5 years
The agency expected that after a sharp drop in 2020 caused by lockdowns, school closures and other Covid response measures, childhood vaccination coverage would rebound in 2021, said Dr. Niklas Danielsson, senior immunization specialist at UNICEF based in Nairobi.
But instead, the problem got worse. DTP3 and measles coverage are at the lowest level since 2008, the report found.
Dr. Danielsson said the vaccination coverage rate in 2021 matched that of 2008. “But since then, birth cohorts have increased, which means the number of children not completing vaccinations, or even starting , is the largest in the last 30 years,” he said.
He and many others in the childhood immunization field had anticipated a recovery last year as health systems learned to adapt to the demands of the pandemic. Instead, misinformation campaigns about Covid vaccinations and broader government distrust of public health measures spread to deter routine immunization, he said.
At the same time, health systems in poorer countries scrambled to carry out limited Covid vaccination, diverting critical access to freezers and health workers to put vaccines into weapons.
The world made sustained progress in childhood vaccination coverage during the 1990s and the first decade of this century. Then the rates began to level off, because the remaining children were the hardest to reach, such as those in active war zones or in nomadic communities. But before the pandemic, there was a redoubled commitment, supported by organizations like the Bill and Melinda Gates Foundation and Gavi, the global vaccine alliance, to try to reach the remaining pockets of children with zero doses. Covid has taken away much of that attention and investment.
In the last two years, India, Nigeria, Indonesia, Ethiopia and the Philippines had the highest number of children who did not receive the vaccines.
Brazil was also on the list of the 10 most affected countries, a stark change for a country once known for its high rates of vaccination coverage. About 26 percent of Brazilian babies had not received vaccinations in 2021, compared to 13 percent in 2018.
“The work of 30 years was lost overnight,” said Dr. Carla Domingues, an epidemiologist and former coordinator of Brazil’s national immunization program.
Vaccination became a politicized issue in Brazil during the covid pandemic, he said. The federal government, led by President Jair Bolsonaro, played down the importance of the coronavirus even as Brazil had one of the highest death rates in the world, saying he would not vaccinate his own 11-year-old son 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 fully accepted,” said Dr. Domingues.
At the same time, anti-vaccination groups that hadn’t had much of a presence in Brazil moved into the country during the pandemic, he said, and misinformation in Portuguese began to circulate on social media.
And all of this was happening, Dr. Domingues said, at a time when Brazilians were a generation away from the serious diseases they were being urged to vaccinate their children against, leading them to question the need.
“Parents don’t know the impact of measles or polio, so they start choosing vaccines,” he said. The data showing that uptake of the pneumonia vaccine is higher than that of polio makes this clear. “Parents choose not to do polio. They say, ‘It’s been 30 years without polio, so do I have to do this?’”
And yet they have a clear signal of risk, he said: Some cases of measles were found in São Paulo earlier this year, six years after Brazil reported it had eradicated the disease. “Measles is now circulating, that gives us a concrete example of what could happen with diphtheria, meningitis and so many other diseases,” he said.
In the Philippines, 43 percent of babies had not received any vaccinations in the past year. There, the problem lies in part with harsh Covid public health measures, including lockdowns. “If you are not allowed to take your children out of certain hours of the day, if they cannot go to school, if the cost of living is increasing, going to a health center to have your child vaccinated falls on your priorities,” said Dr. Danielsson.
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 was later shown to have caused more severe cases of the disease in some who had it. received.
“The Dengvaxia story compounded vaccine hesitancy, particularly among school-age 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 that.”
Unicef’s Ms Caprani said it would take an extraordinary amount of resources and commitment to get vaccine levels back to where they were.
“It’s not going to be enough to just go back to normal and restore regular, routine immunization,” he said. “We are going to need really concerted investment and recovery campaigns, because there is a growing cohort of millions of children who are not vaccinated at all and live in countries that have high levels of malnutrition and other stresses.”
In Zimbabwe, for example, there is currently a measles outbreak in which one in 10 children hospitalized for the disease is dying. (Typical death rates are one in 100 in low-income countries and below one in 1,000 in high-income countries.)
Dr. Fabien Diomande, a polio eradication expert with the Task Force for Global Health who worked for years on polio campaigns in West and Central Africa, said reversing the decline in childhood immunization would require new agility, innovation and resources.
“It’s like we’re in a new world: Those emergencies are not going to go away,” he said. “We will still have Covid. We will continue to have climate crises. We have to learn to work in the context of multiple public health emergencies.”
Dr. Domingues in Brazil said the Covid vaccination efforts could offer some lessons on how to catch up. Brazil achieved high vaccination coverage by providing pop-up vaccination posts and making vaccines available at night and on weekends.
Ms Caprani said that while there was renewed and encouraging interest in global health cooperation due to COVID, investment in new surveillance measures and other developments risked distracting from the simple intervention needed to address the crisis. of childhood immunization: the deployment of thousands of community health workers.
“We are not going to solve this with poster campaigns or social media posts,” he said. “Trusted, well-trained, well-paid community health workers are needed who are there day in and day out, building trust, the kind of trust that means you listen to them about vaccines. And there just aren’t enough of them.”
Jason Gutierrez contributed reporting from Manila.