As of Monday, 36 children have contracted chickenpox at the Asheville Waldorf School, according to Buncombe County health officials.
The North Carolina Department of Health and Human Services said in an email it's the largest chickenpox outbreak in the state since the vaccine was introduced in 1995.
The Asheville Citizen-Times reports that more than two-thirds of the school's 152 students haven't received the vaccine, with many families seeking religious exemptions.
The school enrolls children from early childhood through sixth grade.
Health officials say the outbreak is concerning because the virus can cause hospitalization in rare cases.
School officials didn't immediately respond to an email seeking comment.
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