CNN –A chickenpox outbreak among students at Asheville Waldorf School in North Carolina has grown to 36 cases as of Monday, and exemptions from vaccination were a contributing factor, according to the Buncombe County Health Department, which has been monitoring the situation since the end of October.
Asheville Waldorf School, which serves students from nursery through sixth grade, is part of an educational movement that subscribes to a philosophy focused on physical activity and learning through hands-on tasks, according to its website.
There are more than 900 Waldorf schools in 83 countries, and the Asheville school, which was founded in 2009, is one of about 160 in the United States.
The school is closed for Thanksgiving break and could not be reached for comment.
Chickenpox is a very contagious disease that causes a blister-like rash, itching, tiredness and fever, according to the US Centers for Disease Control and Prevention.
The disease is caused by the varicella-zoster virus, and a vaccine was introduced in 1995.
Two doses of the vaccine, given at ages 12 months through 15 months and then again at 4 through 6 years, are about 90% effective at preventing chickenpox.
Though North Carolina requires vaccination for all children attending schools, the state permits both medical and religious exemptions.
Still, vaccination rates in the state outperformed national figures in 2013 and 2014, according to publicly available information.
Dr. Jennifer Mullendore, the Buncombe County medical director, said that last year, the Asheville Waldorf kindergarten class had the highest percentage of religious exemptions in the county and among the highest in the state.
The state as a whole sees about 1.2% religious exemptions among children enrolled in kindergarten, she said.
Mullendore said the figures from last year are the latest because data has not been gathered and analyzed for the current school year. Read more.
In states such as Texas, Vermont, Washington, and California – where vaccine exemption is legal – Waldorf schools were reported to have a high rate of vaccine exemption within their student populations.
A 2010 report by the UK Government noted that Steiner [Waldorf] schools should be considered “high-risk populations” and “unvaccinated communities” with respect to children’s risks of catching measles and contributing to outbreaks.
On November 19, 2018, the BBC reported there was an outbreak of chickenpox in 36 students at the Asheville Waldorf School located in North Carolina. Out of 152 students at the school, 110 had not received a vaccine for the varicella virus (chickenpox).
Chickenpox can be life-threatening to individuals with weak immune systems, the Canadian Paediatric Society (CPS) and the National Advisory Committee on Immunization recommend that all healthy children 12 months of age and older get the chickenpox vaccine.