Phylogeography and evolutionary dynamics analysis of porcine delta-coronavirus with host expansion to humans

Abstract

From 2003 onwards, three pandemics have been caused by coronaviruses: severe acute respiratory syndrome coronavirus (SARS-CoV); middle east respiratory syndrome coronavirus (MERS-CoV); and, most recently, SARS-CoV-2. Notably, all three were transmitted from animals to humans. This would suggest that animals are potential sources of epidemics for humans. The emerging porcine delta-coronavirus was reported to infect children. This is a red flag that marks the ability of PDCoV to break barriers of cross-species transmission to humans. Therefore, we conducted molecular genetic analysis of global clade PDCoV to characterize spatio-temporal patterns of viral diffusion and genetic diversity. PDCoV was classified into three major lineages, according to distribution and phylogenetic analysis of PDCoV. It can be determined that PDCoV originated in Asia—most likely in Southeast Asia—through inference of migration rate and transmission routes. We also selected six special spike amino acid sequences to align and analyze to find seven significant mutation sites. The accumulation of these mutations may enhance dynamic movements, accelerating spike protein membrane fusion events and transmission. Altogether, our study offers a novel insight into the diversification, evolution, and interspecies transmission and origin of PDCoV and emphasizes the need to study the zoonotic potential of the PDCoV and comprehensive surveillance and enhanced biosecurity precautions for PDCoV.

Comprehensive analysis of codon usage patterns of porcine deltacoronavirus and its host adaptability

“…A previous study by G. Li et al. (2022) suggested that the accumulated mutations in the S gene may enhance dynamics movements and transmission of PDCoV. The recent PDCoV isolates are more adaptable to humans than the early PDCoV strains, indicating that PDCoV gradually adapted to humans by the evolution processes, but further biological assays are needed to confirm this conclusion.…”