• Promising new update on Pfizer vaccine
• Some of Brazil's health workers are barely hanging on as surge worsens
원문출처 : https://www.cnn.com/2021/04/01/health/covid-vaccine-side-effects/index.html
원문출처 : https://www.cnn.com/2021/04/01/health/covid-vaccine-side-effects/index.html