Since the start of the pandemic, scientists have been seeking to better understand immunity to the novel coronavirus. How long is a person immune after having Covid-19, after getting vaccinated, or both? And what could long-lasting immunity mean for booster shots?
원문출처 : https://www.cnn.com/2021/05/28/health/covid-19-immunity-booster-shots-wellness/index.html
원문출처 : https://www.cnn.com/2021/05/28/health/covid-19-immunity-booster-shots-wellness/index.html