Coronavirus biology: viral RNA synthesis, origin, and vaccines



In a recent study published in Current Research in Immunology, researchers analyzed the characteristics of coronaviruses (CoVs) and novel CoV vaccine candidates.

Background

CoVs are a group of positive-strand, enveloped ribonucleic acid (RNA) viruses belonging to the Nidovirales order. There are four genera within the Orthocoronavirinae subfamily: BetaAlphaDelta, and GammaCoV. These four genera of viruses can infect numerous birds and mammals, even humans, and cause various clinical signs according to the affected organ and tissue.

Seven known CoVs can infect humans. Among these CoVs, HCoV-OC43, HCoV-229E, HCoV-HUK1, and HCoV-NL63 produce mild infections comparable to common colds. The Middle East respiratory syndrome coronavirus (MERS-CoV), the severe acute respiratory syndrome coronavirus (SARS-CoV), and the SARS-CoV-2, on the other hand, produce potentially lethal severe respiratory infections. Moreover, the death rates and transmissibility of the three significantly pathogenic human CoVs vary.