SARS-CoV-2: a potential novel etiology of fulminant myocarditis

Coronaviruses are enveloped nonsegmented positive-sense RNA viruses, which are broadly distributed in humans and other mammals, including camels, bats, masked palm civets, mice, dogs, and cats [1]. Although most human coronavirus infections are mild, coronaviruses have caused two large-scale pandemics in the last two decades: severe acute respiratory syndrome (SARS) with a mortality rate of 10%, and Middle East respiratory syndrome (MERS) with a mortality rate of 37%, together causing more than 10,000 cumulative cases [2, 3]. In December 2019, the Chinese city of Wuhan became the center of an outbreak of pneumonia of unknown cause [4]. Several patients with viral pneumonia were found to be epidemiologically associatedwith theHuanan seafoodmarket in Wuhan, where a number of nonaquatic animals such as birds and rabbits were also on sale [5]. Bronchoalveolar lavage fluid (BALF), oral swabs, anal swabs, and blood samples from patients with severe pneumoniawere investigated forpathogendiagnosisat theearlystageof the outbreak. Soon, a novel coronavirus was isolated frompatients, and theSARSCoV-2, previously named “2019 novel coronavirus” (2019-nCoV), was identified using next-generation sequencing [6]. Usually, RNA viruses have a highmutationrate, butanotablecommoncharacteristic of both SARS-CoV and MERSCoV is that they have a low potential for sustained community transmission [7]. Thus, the mutation rate of coronaviruses might also be lower because of their genome-encoded exonuclease [4].