We generated chimeric recombinant SARS-CoV-2 encoding the S gene of Omicron in the backbone of an ancestral SARS-CoV-2

In K18-hACE2 mice, while Omicron causes mild, non-fatal infection, the Omicron S-carrying virus inflicts severe disease with a mortality rate of 80%.

Boston University School of Medicine researchers combined the Omicron spike (S) protein with the ancestral strain of SARS-CoV-2 to create a more fatal yet highly transmissible virus as Omicron. Doesn't this mean lab engineered virus is possible? Why are they still doing this? What's the purpose of such research? If China loosen the zero-covid policy, couldn't someone be sent to spread this kind of virus intentionally?

Remember the SH outbreak in late Mar to Apr? Just around the time when lock-down commence, some people tried to escape from SH in violation of the lock down. In particular, these two woman, ethnic Chinese from US IIRC, who lied that they've lost their cell phone and lied about their health code. Instead of traveling from SH straight back to their home in Hangzhou, they traveled for hours around Hangzhou city visiting various places with mask down until the health personnel located them in a coffee outlet. They laughed at the health personnel when they were found. An investigation was launched against their case.