Here we present the results of a bibliometric survey of peer-reviewed and pre-print papers published in the English language on issues related to COVID-19 within the first three months since a cluster of a severe acute respiratory disease of unknown etiology was officially confirmed by the Chinese Center for Disease Control and Prevention on 31 December 2019. A systematic search using PubMed/Medline and Scopus databases and preprint servers was performed. The articles were classified according to their type, subject and country of origin. Up to 31 March 2020, a total of 2062 papers published in 578 peer-reviewed journals and 1425 preprints posted mostly on medRxiv (55.4 %), were identified. The mean number of published journal papers and preprints per day in the considered period was 27 and 12, respectively, and reached a maximum of 51 and 46 per day in March, respectively. The identified articles, journal papers and preprints, mostly covered the epidemiology of COVID-19 (35.7 %), clinical aspects of infection (21.0 %), preventative measures (12.8 %), treatment options (12.5 %), diagnostics (12.2 %), mathematical modeling of disease transmission and mitigation (9.6 %), and molecular biology and pathogenesis of SARS-CoV-2 (8.7 %). The majority of the journal papers were commentaries (38.5 %), reviews (33.6 %) and original research (21.3 %), while preprints predominantly presented original results (89.8 %). Chinese scientists contributed the highest share of original research and were responsible for 32.9 % journal papers and 43.9 % preprints published in the considered period. A high number of contributions was also seen from the United States, the United Kingdom, and Italy. The benefits and potential risks of such a massive publication output are discussed. The scientific response seen during the first 3 months of the COVID-19 outbreak is a demonstration of the capabilities of modern science to react rapidly to emerging global health threats by providing and discussing the essential information for understanding the etiological factor, its spread, preventative measures, and mitigation strategies.