Stat reports that researchers at BU's National Emerging Infectious Diseases Laboratories on Albany Street- designed to study killer microorganisms - grafted the spike of an omicron variant of the virus onto one of the OG strains from Wuhan to see whether something on the spike was changing the virus's virulence.
Apparently, while the new spike makes omicron better able to get through people's immune systems, it did not make the "chimeric" version more virulent - sure, it killed 80% of the mice it was injected into, but the original virus killed 100%.
So no, BU didn't create an even deadlier Covid-19 virus. BU adds the work was approved by both an internal BU safety committee and the Boston Public Health Commission. Still, Stat adds federal research honchos are a bit miffed that they didn't know what BU researchers using their money were up to -they say they first learned about the work from media reports.
Role of spike in the pathogenic and antigenic behavior of SARS-CoV-2 BA.1 Omicron - the complete, if un-peer-reviewed - study.