Measles deaths globally spiked by more than 40% last year and cases rose after vaccination levels dramatically dropped during the pandemic, leading health agencies said Thursday.

The highly infectious disease triggered epidemics in 37 countries last year, versus 22 countries in 2021. It sickened 9 million children and killed 136,00, mostly in poorer countries, the World Health Organization and the U.S. Centers for Disease Control and Prevention said in a new report.

The number of measles cases also rose by nearly 20% after immunization levels dropped to their lowest in 15 years during the pandemic, the agencies said.