标题: Covid-19 Likely in U.S. in Mid-December 2019 [打印本页] 作者: lixue123 时间: 2021-3-26 02:19 标题: Covid-19 Likely in U.S. in Mid-December 2019
The findings significantly strengthen evidence suggesting the virus was spreading around the world well before public health authorities and researchers became aware, upending initial thinking about how early and quickly it emerged.
