A novel human coronavirus OC43 genotype detected in mainland China

Abstract

Dear Editor, Coronaviruses (CoVs) have a broad spectrum in humans and other animals, causing asymptomatic infections or respiratory tract infections, gastroenteritis, and neurological diseases of varying severity 1-3 . CoVs are the largest known RNA viruses, belonging to the family Coronaviridae 4 . On the basis of serology and genome phylogeny, CoVs are divided into four genera named Alpha-, Beta-, Delta-, and Gamma-coronavirus 5,6 . To date, six human coronaviruses (HCoVs) have been identified, including two -CoVs (HCoV-229E and HCoV-NL63) and four -CoVs (HCoV-OC43, HCoV-HKU1, severe acute respiratory syndrome CoV (SARS-CoV) and Middle East respiratory syndrome CoV(MERS-CoV)) Human coronavirus OC43 (HCoV-OC43) is more predominant than other HCoVs, especially in children and elderly persons In addition to the high nucleotide substitution rates, the genotype shift by natural recombination of HCoV-OC43 is thought to be an adapting mechanism for maintaining its epidemic Since the first isolation of HCoV-OC43 in the 1960s, seven genotypes (A-G) have been identified by phylogenetic analysis of the main genes, such as spike (S), RNA-dependent RNA polymerase (RdRp) and nucleocapsid (N), as well