Positive cases of the virus are currently spiking across UK, with 5,975 people testing positive in England in the seven days leading to December 9 - an increase of 38.6 per cent compared to the week before, the Mirror reports
Experts have warned that the latest Covid wave could be one of the worst since the vaccine was introduced, the report said.
A "nasty" bout of coronavirus is said to be circulating in the UK amid low levels of immunity among the population, while official health statistics show that cases continue to rise, the Mirror added.
Scientists specialising in immune systems have said Covid is still causing infections that could be worse in their symptoms than previous waves.
Quoting BBC News, the report said that low antibody levels and waning immunity to the virus could be factors leading to more severe infections. Prof Eleanor Riley, an immunologist at the University of Edinburgh, said she had her own "horrid" bout of Covid that was "much worse" than expected. She added "People's antibody levels against Covid are probably as low now as they have been since the vaccine was first introduced. Now, because antibodies are lower, a higher dose [of the virus] is getting through and causing a more severe bout of disease."
Further, citing Prof Peter Openshaw, from Imperial College London, the report said: "The thing that made the huge difference before was the very wide and fast rollout of vaccines - even young adults managed to get vaccinated, and that made an absolutely huge difference". With fewer people being offered a booster vaccine this winter, Prof Openshaw said it's possible that a lot of people could end up having a "pretty nasty illness that is going to knock them out for several days or weeks".
"I'm also hearing of people having nasty bouts of Covid, who are otherwise young and fit," he continued. "It's a surprisingly devious virus, sometimes making people quite ill and occasionally leading to having 'long Covid."
"The viruses circulating now are pretty distant immunologically from the original virus which was used to make the early vaccines, or which last infected them. A lot of people have very little immunity to the Omicron viruses and their variants."