About 20 states already require chicken pox vaccinations for children starting school or day care. It is aiming for 95 percent by age 5. It remains unclear if patients are immune for life or need a booster dose. Because chicken pox is often more serious in adulthood, some parents in the past tried to expose their children to the disease while they were young. Seward said the vaccine may eventually prove useful also in fighting shingles, a disease caused by the same virus as chicken pox.
Shingles cause a painful skin rash and sometimes chronic pain.