LONDON — Nearly 170 million children worldwide, including more than 2.5 million in the United States and half a million in Britain, missed out on the first dose of the measles vaccine during the past eight years, opening the door to global outbreaks of the disease, a Unicef report said on Thursday.
“The ground for the global measles outbreaks we are witnessing today was laid years ago,” Henrietta Fore, the executive director of Unicef, the United Nations agency for children, said in a statement. “The measles virus will always find unvaccinated children,” she added.
Unicef cited a lack of access to the vaccine, poor health care, complacency, and fear or skepticism about vaccines in general as reasons for the disturbing trend.
The rise of the anti-vaccination movement, whose members are known as anti-vaxxers, in the United States and the rest of the world may be linked to the vaccine rejection, which Simon Stevens, the director of Britain’s National Health Service, called “a serious and growing public health time bomb.”
The rejection has been encouraged by the spread of false information, often on social media platforms, about supposed links between vaccines and autism, a theory roundly rejected by scientists and doctors.
“With measles cases almost quadrupling in England in just one year, it is grossly irresponsible for anybody to spread scare stories about vaccines, and social media firms should have a zero-tolerance approach towards this dangerous content,” Mr. Stevens said in a statement on Wednesday.
Measles, a highly infectious viral disease that is more contagious than Ebola or tuberculosis, is still an important cause of death among young children globally, the World Health Organization said.
More than 365 children die from measles every day, according to Unicef, and the disease can also cause blindness, deafness or brain damage.
Two doses of the same combined vaccine — for measles, mumps and rubella — are required to protect children from the disease. For a whole community to be safe, including babies and others who have yet to be vaccinated — so-called herd immunity — 95 percent immunization coverage is required. But global coverage is much lower: In 2017, worldwide coverage was reported at 85 percent for the first dose and 67 percent for the second, Unicef said.
Nearly 169 million children worldwide missed out on the first dose, with an average of more than 21 million children missing out every year from 2010 to 2017. More than 2.5 million children in the United States, and more than half a million children in France and Britain, did not get the first measles vaccine dose between 2010 and 2017.
Could this number be high enough to affect Britain’s herd immunity? It depends, said Anna Schurich, an immunology lecturer at King’s College London.
“If you have pockets of parents not vaccinating and they all live close together, then even relatively low numbers of nonvaccinated children can become problematic, as they could potentially infect each other,” she said. “If unvaccinated children are very spread out, then the risk is, of course, lower,” she added.
Britain eliminated measles in 2016, the government said. But though the disease is no longer native to the country, Britain has experienced recent measles outbreaks, and immunity levels among mostly young people remain lower than required.
“Measles is one of the most infectious known diseases, so it can take only one infected person in an area with lower vaccination rates to cause an outbreak,” Public Health England, a government body, said in a statement in January.
Outbreaks of the disease have been reported in British cities such as Leeds, Liverpool, Birmingham and Surrey since October 2017, according to the National Health Service. But Manchester appears to be a focal point of the disease in the country, with 47 cases of measles there since the start of the year, Public Health England said last week. Last year, the city had three cases total, the BBC reported.
The rise of the illness in Britain is in accordance with a disconcerting trend worldwide.
The United States, for example, had reports of 695 cases of measles this year — the highest annual number recorded since the disease was eradicated in the country in 2000 — federal health officials said on Wednesday.
Unicef warned in March that measles has been surging globally: Countries with no reported cases of measles in 2017 experienced an outbreak of hundreds of cases last year.
Brazil — where the absence of measles cases in 2017 was followed by a staggering 10,262 cases in 2018 — topped that list. Then came Moldova, with 312 cases in 2018, and Montenegro with 203.
“Measles may be the disease, but, all too often, the real infection is misinformation, mistrust and complacency,” Ms. Fore said at the time.
In some cases, people don’t take the disease seriously enough, as they don’t often see the danger in their immediate environment, Ms. Schurich said in a phone interview on Thursday. In other cases, it may be because they deem the vaccines to be unsafe or against nature.
“I think there is a kind of new movement maybe generally against medicine, but especially vaccination, that vaccination is not natural,” she said.
The anti-vaccine movement has been growing across Europe, most notably in Poland, according to a European Union report published last year. The number of vaccine refusals in the country increased to 23,147 in 2016 from 4,893 in 2007, the report said.
The Czech Republic, Finland and Sweden have also experienced a drop in vaccine confidence, according to the report. But other European countries are taking a different stance.
In Italy, a decline in vaccinations nationwide and a measles outbreak prompted the government to bar about 300 children in the city of Bologna from attending kindergarten in March, enforcing a law that said children enrolled in schools must have 10 vaccines.
It was a far cry from a temporary measure the government adopted last year — after years of the governing Five Star Movement helping to foment confusion about vaccines — that allowed children to stay in school as long as their parents attested they had been vaccinated. A doctor’s note was not needed.
