Covid scientists are being warned against researching on a new mutated strain that caused a 100 per cent fatality rate in "humanised mice".
The deadly virus, known as GX_P2V, attacked the brains of mice that were engineered to reflect similar genetic makeup as humans.
Researchers noted a "surprisingly" rapid death rate after all the mice infected died within just eight days.
Within the days before their deaths, the rodents had quickly lost weight, exhibited a hunched posture and moved extremely sluggishly.
Covid-19 continues to infect people of all ages across the UK
PA
The study also found their eyes turned completely white the day before they died.
However, scientists warned about the legitimacy of the study, saying it was "pointless."
Epidemiology expert at the University College London's Genetics Institute said: "I can see nothing of vague interest that could be learned from force-infecting a weird breed of humanised mice with a random virus. Conversely, I could see how such stuff might go wrong."
Retired Stanford professor of medicine Dr Gennadi Glinsky added: "This madness must be stopped before too late."
It is not clear how the strain will impact humans.
LATEST DEVELOPMENTS
A study found under-vaccinated people aged over 75 were more than twice as likely to suffer a severe Covid-19 outcome than those who were fully protected
PA
It comes after Scientists warned a new strain of Covid could cause potential heart issues.
Research into the the new strain known as JN.1, could cause "global healthcare risk" related to Covid-19, stating that it could start a "heart failure pandemic."
Closer to home, older people are being urged to become fully vaccinated as a study showed thousands of hospital admissions and deaths in the UK could have been avoided if everyone was fully jabbed.
Around 90 per cent of the population over the age of 12 were vaccinated with at least one dose by January 2022.
However, less than half the population were fully jabbed by June 2022.
A study found the highest rates of under-vaccination were in younger people, men, those in areas of higher deprivation, and people of non-white ethnicity.
Director of the Usher Institute at Edinburgh Medical School Professor Sir Aziz Sheikh said: "Covid-19 vaccines save lives.
"As new variants emerge, this study will help to pinpoint groups of our society and areas of the country where public health campaigns should be focused and tailored for those communities."
