One in five children in the United States had a “vaccine hesitant” parent last year, according to new research from the Centers for Disease Control and Prevention. Parental concerns over vaccine safety have contributed to several major outbreaks of preventable diseases in the U.S. and other countries in recent years. The 2019 measles outbreak in the US — the largest number of cases in 27 years — was largely driven by parents in New York and Washington state who failed to follow childhood vaccine guidelines.
