asymptomatic       
adjective uk/ˌeɪ.sɪmp.təˈmæt.ɪk/ us/ˌeɪ.sɪmp.təˈmæt̬.ɪk/
 medical specialized无症状的 
showing no symptoms of a particular disease
  asymptomatic HIV infection  无症状HIV感染 
 Evidence suggests that many Ebola infections are asymptomatic.  证据显示许多伊波拉病毒感染是无症状的。 
 Most people with chlamydia are asymptomatic and do not seek testing.  大部分衣原体携带者无症状并且不会主动寻求检测。