Last Updated on October 18, 2022
Researchers at Boston University have engineered a strain of COVID-19 that was lethal in 80% of infected mice. In addition to increased lethality, the engineered COVID strain was found to be more infectious. The series of experiments mirrors those that potentially spawned the initial pandemic strain in Wuhan, China.
The engineered variant, which was a mixture of omicron and the initial Wuhan variant, killed 80% of the mice it infected, Boston University researchers said.
When mice were exposed to omicron only, they experienced mild symptoms. This is similar to the effects Omicron has on humans, including those who have been vaccinated. Omicron has been demonstrated to be highly infectious, though less lethal.
The research was conducted by a team of scientists from Florida and Boston at the university’s National Emerging Infectious Diseases Laboratories.
Researchers extracted the spike protein from Omicron and infused it with the initial strain that emerged in Wuhan in late 2019. They then observed and documented how the new strain affected mice.
“In…mice, while Omicron causes mild, non-fatal infection, the Omicron S-carrying virus inflicts severe disease with a mortality rate of 80 percent,” researchers wrote in a paper detailing their findings.
In addition to increased lethality, the engineered COVID strain has five times more infectious virus particles than the Omicron variant, researchers said. The team also noted that the breed of mice used in the study could have partially affected results, as other breeds share more similarities with humans.
The majority of global public health officials have long maintained that the virus emerged from a national at a wet market in Wuhan, China. But evidence has emerged to suggest that the virus perhaps emerged in a lab, as the Wuhan Institute of Virology is located not far from the wet market.