At least 75% percent of all children in North Korea missed routine vaccinations during the pandemic, U.N. aid agencies announced Monday, leaving them more vulnerable to death and disease.

In a press release, the World Health Organization (WHO), UNICEF and the vaccine alliance Gavi listed North Korea among 20 countries that are the priority target of a new campaign to make up for missing the important vaccinations in 2021.

“Routine vaccines are typically a child’s first entry into their health system and so children who miss out on their early vaccines are at added risk of being cut out