Since the vaccine against chickenpox became available in the United States, the country is seeing a lot less of the disease.
Between 2000 and 2010, the incidence of chickenpox declined nearly 80 percent, from 43 cases per 100,000 people, to nine cases per 100,000 people, according to a new report from the Centers for Disease Control and Prevention (CDC). The report included information from 31 states.
The biggest declines were seen in children ages 5 to 9, the CDC says.
In 2010, four people died from chickenpox, none of whom had been vaccinated.
The chickenpox vaccine was introduced in 1996, and for 10 years, just one dose of the vaccine was used. In 2006, children were recommended to receive two doses, one between ages 12 and 15 months, and a second between 4 and 6 years old.
The declines in chickenpox cases were greatest after the introduction of this second dose. Between 2000 and 2005, the incidence of chickenpox declined 43 percent, compared with 72 percent between 2006 and 2010.
Further declines in chickenpox are expected as more people get vaccinated with two doses, the CDC said.
To continue monitoring the impact of the two-dose chickenpox vaccine, a strengthened surveillance system and participation from all states is needed, the CDC says.
Pass it on: Cases of chickenpox have steeply declined since the vaccine was introduced.
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