无症状感染者 
asymptomatic patient 
 

图源：CNN视频截图

当地时间4月3日，美国总统特朗普表示，美国疾控中心推荐美国民众佩戴布口罩遮挡面部，防止感染。这一表态，与此前美国疾控中心“民众不需要戴口罩，除非正在照顾病人”这一指导意见相反。美国疾控中心网站解释称，新的建议是在研究无症状感染者的基础上做出的。无症状感染者不表现症状，但是仍具有传染力。

On April 3, US President Donald Trump said the Centers for Disease Control and Prevention (CDC) now recommended that Americans wear cloth face coverings to protect against COVID-19. It is contrary to their former guidelines, which stated that “people do not need to wear a face mask unless you are caring for someone who is sick”. The CDC’s website explained that the recommendations were updated following new studies on asymptomatic patients. These are infected people who don’t display any symptoms of the disease, but can still transmit it. 

马上学：Asymptomatic作形容词，意为“无症状的”，其反义词为symptomatic，意为“有症状的”，常见搭配为be symptomatic of sth（作为症状的、表明……的），例如：The city’s problems are symptomatic of the crisis that is spreading throughout the country.