美国人的认知让人着急-还不戴口罩？

传染性在有症状前后一个星期内最强，病毒在鼻腔与咽喉大量生长。。。。Science news Coronavirus is most contagious before and during the first week of symptoms People stop making infectious virus once the body’s antibody response kicks in microscope image of coronavirus The coronavirus that’s causing a global pandemic (orange) is shown emerging from a cell (gray). The virus can grow easily in people’s noses and throats and may be transmitted before people are aware they are sick, a new study suggests.

所有跟帖： 

• 说口罩没用的愚民政策害的。 -辽阔的海- ♂ (0 bytes) () 03/23/2020 postreply 07:27:38

• 医护人员都没有那 -idleman- ♂ (0 bytes) () 03/23/2020 postreply 07:36:00

• 是的，但要说实话，不要愚民。 -辽阔的海- ♂ (0 bytes) () 03/23/2020 postreply 07:38:28

• 单口罩这事，不向古老的中国文明学习，要吃大亏 -xuall- ♂ (0 bytes) () 03/23/2020 postreply 07:37:00