SUMMARYIn recent decades, several new diseases have emerged in different 
geographical areas, with pathogens including Ebola virus, Zika virus, Nipah 
virus, and coronaviruses (CoVs). Recently, a new type of viral infection emerged 
in Wuhan City, China, and initial genomic sequencing data of this virus do not 
match with previously sequenced CoVs, suggesting a novel CoV strain (2019-nCoV), 
which has now been termed severe acute respiratory syndrome CoV-2 (SARS-CoV-2). 
Although coronavirus disease 2019 (COVID-19) is suspected to originate from an 
animal host (zoonotic origin) followed by human-to-human transmission, the 
possibility of other routes should not be ruled out. Compared to diseases caused 
by previously known human CoVs, COVID-19 shows less severe pathogenesis but 
higher transmission competence, as is evident from the continuously increasing 
number of confirmed cases globally. Compared to other emerging viruses, such as 
Ebola virus, avian H7N9, SARS-CoV, and Middle East respiratory syndrome 
coronavirus (MERS-CoV), SARS-CoV-2 has shown relatively low pathogenicity and 
moderate transmissibility. Codon usage studies suggest that this novel virus has 
been transferred from an animal source, such as bats. Early diagnosis by 
real-time PCR and next-generation sequencing has facilitated the identification 
of the pathogen at an early stage. Since no antiviral drug or vaccine exists to 
treat or prevent SARS-CoV-2, potential therapeutic strategies that are currently 
being evaluated predominantly stem from previous experience with treating 
SARS-CoV, MERS-CoV, and other emerging viral diseases. In this review, we 
address epidemiological, diagnostic, clinical, and therapeutic aspects, 
including perspectives of vaccines and preventive measures that have already 
been globally recommended to counter this pandemic virus.