Study Finds No Evidence of Pre-Adaptation for Pandemic Viruses Including SARS-CoV-2 (cidrap.umn.edu)

• Evolutionary analysis shows no pre-zoonotic adaptation for most pandemic viruses, including SARS-CoV-2.
• The 1977 H1N1 pandemic strain shows molecular evidence of laboratory passage, consistent with a failed vaccine trial.
• Findings challenge the need for rare adaptations and emphasize reducing human exposure to animal viruses.

"A UC San Diego-led study published in Cell analyzed viral genomes and found that most pandemic viruses, including SARS-CoV-2, did not require evolutionary adaptation before jumping to humans. The research challenges claims that SARS-CoV-2 was lab-engineered or adapted in an intermediate host. However, the 1977 H1N1 influenza reemergence showed signs of laboratory passage. The study suggests that many viruses already have the capacity for human-to-human transmission and that spillover risk depends more on human exposure."