The World Health Organization and the US Centers for Disease Control and Prevention announced on Wednesday that measles is rapidly spreading in multiple regions across the world.
They agencies blamed the resurgence of measles on a decrease in childhood vaccination during COVID-19 and less monitoring of the illness, Reuters reported.
Measles is considered extremely contagious and only preventable among a population if there is a 95 percent vaccination rate.
There were around 40 million children who did not get a measles vaccine in 2021 because of increased difficulties in accessing medical treatments during COVID, the WHO and the CDC said in a joint statement.
The agencies warned that action needs to be taken immediately to prevent a global problem.
It is assumed that multiple factors have kept measles rates from increasing to historic levels, including the continuation of social distancing and the cycling nature of the disease. But experts say that could change quickly given how contagious measles is.