Genetic relatedness of the novel human group C betacoronavirus to Tylonycteris bat coronavirus HKU4 and Pipistrellus bat coronavirus HKU5

Woo, Patrick CY; Lau, Susanna KP; Li, Kenneth SM; Tsang, Alan KL; Yuen, Kwok-Yung

In the last decade, we have already witnessed the discovery of two novel human CoVs and an animal-to-human CoV interspecies jumping event on SARSr-CoVs. In contrast to HCoV-229E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1, which are notoriously difficult to culture, HCoV-EMC and human SARS-CoV are both readily cultivable using primate cell lines. This may suggest a possible correlation between cultivability and virulence/recent interspecies jumping. Sequencing more genomes and performing evolutionary analysis will help us understand whether HCoV-EMC represent another recent interspecies jumping event from animal to human or another human CoV that has stably infected human. Our most recent findings showed that CoVs can be transmitted between two bat species of different suborders, suggesting that different degrees of interspecies jumping can occur in nature. 19 More intensive surveillance studies for group C betaCoVs in bats and other animals may reveal the natural host of this novel human group C betaCoV. As coronaviruses are prone to recombination and mutation and it has been documented that different levels of interspecies jumping can indeed occur in nature, we should not underestimate the potential of coronaviruses being the cause of another major ''SARS-like'' pandemic.