In an effort to research what makes Omicron so transmissible – and funded in part by grants from the NIH and Anthony Fauci’s NIAID, the researchers cobbled the Omicron spike protein to the original strain of Covid-19. The resulting virus was five times more infectious than Omicron.

“The Omicron spike (S) protein, with an unusually large number of mutations, is considered the major driver of these phenotypes. We generated chimeric recombinant SARS-CoV-2 encoding the S gene of Omicron in the backbone of an ancestral SARS-CoV-2 isolate and compared this virus with the naturally circulating Omicron variant,” reads the pre-print.

The new research, which has not been peer-reviewed, was conducted by a team from Boston and Florida.

“In…mice, while Omicron causes mild, non-fatal infection, the Omicron S-carrying virus inflicts severe disease with a mortality rate of 80 percent,” the researchers wrote, adding that while the spike protein is responsible for infectivity, changes to other parts of its structure are responsible for its deadliness.