A dangerous decline in the rate of children vaccinated against measles is spurring a global increase in cases and deaths from the highly contagious virus, according to a report released Thursday.
Estimated measles cases rose 18% to 9 million in 2022 when compared to the previous year, and deaths rose by 43% to 136,200, according to the report, jointly authored by the World Health Organization and the Centers for Disease Control and Prevention.
The problem is mounting, with year-to-date numbers for 2023 on track to potentially double the 2022 figures, Natasha Crowcroft, the WHO’s global lead for measles and rubella, told STAT in an interview.
“If this carries on the direction it’s going in, this is going to be a disaster for children in the most vulnerable settings,” Crowcroft said.
Whereas in 2022 there were large or disruptive outbreaks of measles in 37 countries — up from 22 in 2021 — a total of 47 countries have reported such outbreaks already in 2023, she said.
Measles is such a contagious disease that before vaccines were developed nearly everyone contracted the virus in childhood. For most, the illness consisted of a nasty flu-like illness with an itchy full-body rash. But measles can kill, especially in settings where children are malnourished or have other underlying health conditions.
The advent of widespread vaccination brought down case and death rates substantially, with the report estimating that about 57 million measles deaths were averted between 2000 and 2020 thanks to the vaccine.
During that period, the estimated global coverage of the first dose of measles-containing vaccine increased from 72% to 86%; to be maximally effective, the vaccine requires two doses. The first-dose coverage figure fell to 81% in 2021 during the Covid-19 pandemic, the lowest rate since 2008. It is estimated that it takes 95% coverage with two doses of vaccine to stop spread of measles, a target that an increasing number of countries are missing. The report said the global measles two-dose coverage rate was only 74% in 2022.
Vaccination rates have been declining in upper-income countries due to vaccine hesitancy. In lower-income countries, the declines are attributed to weak health care systems, inadequate funding, and security challenges — issues that were all exacerbated by the pandemic, which eroded the ability of public health workers around the world to reach unvaccinated children.
“The increase in measles outbreaks and deaths is staggering, but unfortunately, not unexpected given the declining vaccination rates we’ve seen in the past few years,” John Vertefeuille, director of CDC’s Global Immunization Division, said in a statement. “Measles cases anywhere pose a risk to all countries and communities where people are under-vaccinated. Urgent, targeted efforts are critical to prevent measles disease and deaths.”
Crowcroft said getting measles control higher up on the list of international health priorities is a continual challenge.
“To me, it’s quite chilling. And I think, unless nations and regions and countries, at the global level really say, ‘This has got to be a huge priority. We’ve got to address this now,’ this is just going to get much worse. And a lot of kids are going to die,” she said.