COVID-19 pandemic is a new health phenomenon, which requires detailed investigations. Several factors may enhance COVID-19 publication productivity. First, many journals established free open-access for papers on COVID-19 [7]. Moreover, the most valuable reports may also be rapidly reviewed. Many governmental and private institutions donated funds for research on SARS-CoV-2 and its spread [8-10]. Finally, media coverage of scientific progress related to COVID-19 remains intense [11,12]. In these circumstances, researchers have additional motivation to rapidly publish their results.