Before the vaccine was available, Chickenpox was very common in the United States. About 4 million people would get the disease each year, about 10,600 people were hospitalized and 100 to 150 died each year because of it. CDC recommends two doses of chickenpox vaccine for children, adolescents, and adults, which are about 98% effective at preventing chickenpox.
(From: Centers for Disease Control and Prevention – Chickenpox)
