Mounting evidence suggests that the novel coronavirus can be transmitted from presymptomatic or asymptomatic individuals, bolstering the argument for maintaining proper social distancing measures and possibly impacting the case-fatality rate for COVID-19, a new review from the Centers for Disease Control and Prevention (CDC) said.
The agency looked at reports pertaining to presymptomatic and asymptomatic transmission that was published in PubMed from Jan. 1 to April 2, which is when the CDC recommended that the public wear face coverings to further stop the spread of COVID-19. The instances of such transmission included reports of China, Germany and Singapore.
“As the coronavirus disease pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) unfolds, an increasing number of reports have indicated that some infected persons may not exhibit signs or symptoms of illness, including persons who are presymptomatic (SARS-CoV-2 RNA is detectable before symptom onset) or asymptomatic (SARS-CoV-2 RNA is detectable but symptoms never develop),” researchers wrote. “The detection of SARS-CoV-2 RNA in presymptomatic or asymptomatic persons does not prove that they can transmit the virus to others. We describe evidence that supports the concept of transmission while presymptomatic and asymptomatic, which we found during a rapid literature review conducted at the Centers for Disease Control and Prevention (CDC) in early April 2020.”