KIEV, UKRAINE - MAY 15: Sonya Yanchuk,
age 1, sits in her mother Nadia Yanchuk's lap as nurse Mariana Gonchara (L) administers a measles vaccine shot in health clinic № 10 on May 15, 2019 in Kiev, Ukraine. As Ukraine struggles with its largest measles outbreak in decades, registering 35,000 cases and 14 deaths in the first three months of 2019, the disease has spread to other European countries and the United States. (Photo by Brendan Hoffman/Getty Images)