Boston University scientists were today condemned for 'playing with fire' after it emerged they had created a lethal new Covid strain in a laboratory.
revealed the team had made a hybrid virus — combining Omicron and the original Wuhan strain — that killed 80 per cent of mice in a study.
The revelation exposes how dangerous virus manipulation research continues to go on even in the US, despite fears similar practices may have started the pandemic.
Professor Shmuel Shapira, a leading scientist in the Israeli Government, said: 'This should be totally forbidden, it's playing with fire.'
Gain of function research - when viruses are purposefully manipulated to be more infectious or deadly - is thought to be at the center of Covid's origin.
A Chinese laboratory located just miles from the first cluster of cases carried out similar research on bat coronaviruses.
But the practice has been largely restricted in the US since 2017.
Dr Richard Ebright, a chemist at Rutgers University in New Brunswick, New Jersey, toldthat: 'The research is a clear example of gain of function research.
He added: 'If we are to avoid a next lab-generated pandemic, it is imperative that oversight of enhanced potential pandemic pathogen research be strengthened.'
In the new research , which has not been peer-reviewed, a team of researchers from Boston and Florida extracted Omicron's spike protein — the unique structure that binds to and invades human cells. It has always been present but it has become more evolved over time. Omicron has dozens of mutations in its spike protein that made it so infectious. Researchers attached Omicron's spike protein to the original wildtype strain that first emerged in Wuhan at the start of the pandemic. The researchers looked at how mice fared under the new hybrid strain compared to the original Omicron variant