21-01-12 World Health Organization (WHO) chief scientist Soumya Swaminathan said Monday that herd immunity to coronavirus would not be achieved in 2021, despite the growing availability of vaccines. 世界卫生组织的首席科学家苏米娅斯瓦米纳坦周一表示，即使疫苗...

20-10-20 Using the principle of so-called herd immunity to stem the COVID-19 pandemic is unethical and not an option countries should pursue to defeat the virus, the UN health agency chief warned on Monday. 世界卫生组织总干事谭德塞警告称，用所谓的群体免疫原...