Search method
We searched the literature in Google Scholar and PubMed for articles that were published from January 1 through May 5 2020. Searching was concerned with asymptomatic coronavirus 2 (SARS-CoV-2) implications. We used combinations of the search terms SARS-CoV-2, COVID-19, Corona Virus, asymptomatic, presymptomatic, transmission, and implication. “AND”, and “OR” Boolean operators were used to combine the search terms especially in PubMed advanced searching. We included original articles, brief reports, and correspondences and excluded reviews, commentaries, opinions, and preprint manuscripts. We classified studies as reporting epidemiology, geographic distribution, and timing of asymptomatic implications of SARS-CoV-2.