Human Coronaviruses: General Features

Human coronaviruses (HCoVs), including HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1, are traditionally known to cause symptoms of common cold with only moderate clinical impact. Severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), on the other hand, have strike humans in the past two decades as highly fatal human pathogens leading to considerable mortality and economic loss. This article summaries the updates on the structure, genome organization, replication and clinical features of human coronaviruses. Recent studies also shed light upon the zoonotic origin of emerging human pathogens including SARS-CoV and MERS-CoV, providing insight for future surveillance and intervention.