Dynamics of natural selection preceding human viral epidemics and pandemics - PubMed
5 days ago
- #natural selection
- #zoonotic viruses
- #viral emergence
- The study investigates whether zoonotic viruses require adaptation before causing human epidemics.
- No significant change in selection intensity was found before outbreaks in humans for Ebola, Marburg, mpox, influenza A, and SARS-CoV-2 viruses.
- A change in selection was observed for SARS-CoV in an intermediate host.
- Extensive pre-zoonotic adaptation is not necessary for human-to-human transmission of zoonotic viruses.
- The reemergence of H1N1 influenza A virus in 1977 was preceded by a shift in selection intensity, suggesting possible laboratory passage.
- Phylogenetic analysis of selection regimes can detect evolutionary signals of host switching or laboratory passage.