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2. Centers for Disease Control and Prevention. Covid-19 by county. 25 February 2022. www.cdc.gov/coronavirus/2019-ncov/your-health/covid-by-county.html.
3. Mandavilli A. New CDC guidelines suggest 70 percent of Americans can stop wearing masks. New York Times. 25 February 2022. www.nytimes.com/2022/02/25/health/cdc-mask-guidance.html.
4. Open Letter: Public health researchers and practitioners urge elected officials to revaluate the end of school mask mandates. https://medium.com/@pubhealthschoolmasks/open-letter-public-health-school-mask-mandates-e3a7071f3b26.