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Covid: Urgent call to update vaccines to target variants as cases rise to near-record levels

Covid vaccines must be urgently updated to target new variants as infection rates in the UK soar to near-record levels, leading scientists have warned.

An average of 285,507 people are being infected with the virus each day in the UK, according to the latest data from the ZOE Covid Study. Its lead scientist Professor Tim Spector said cases were soon expected to exceed the 300,000 mark, “bringing us to levels seen during the height of the pandemic for the UK”.

With the country now in its fifth wave, and hospital admissions once again on the rise, scientists argue a new vaccine specific to Omicron could offer better protection against future variants, helping keep people out of hospital and reduce cases.

Professor John Edmunds, a leading epidemiologist and member of Sage, said the results of a recent study looking at a two-in-one vaccine specific to the original Covid virus and Omicron variant were “encouraging”.

Protection against infection and hospitalisation from Omicron wanes within a matter of months after a third dose. After a booster jab, effectiveness in preventing admission to hospital drops from 91.6 per cent to 72.5 per cent over 10 weeks, according to government analysis.

Fourth doses are already being rolled out to certain groups, including the elderly, with another booster set to be offered in the autumn – but experts believe it is time to update the vaccines in the hope of offering broader and longer-lasting protection against the variants.

Data published last week by Moderna showed that its “bivalent” jab offers good protection against Omicron that lasts longer than the original vaccine. It also increases immunity against the Omicron sub-variants BA.4 and BA.5, which are driving the current surge in UK cases.

“I do think that the use of a vaccine that offers broader protection [as a bivalent vaccine should do] is the way forward,” said Prof Edmunds. “I think that there is a case for it.”

Professor David Robertson, head of viral genomics and bioinformatics at the University of Glasgow’s Centre for Virus Research, said an updated vaccine booster specific to Omicron should be made available for all.

“Omicron (particularly BA.5) is clearly more than able to infect vaccinated people, and continues to evolve unpredictably, so protecting people from it and future variants is the logical thing to do.

“It seems sensible to give it [an updated vaccine] to everybody. If we end up with these new variants infecting lots of people, then you get lots of sick people – it just seems a no brainer to vaccinate people.”

Recent data from Japan suggests that BA.4. and BA.5, which are more transmissible than the original Omicron variant, could also be capable of causing more severe infections – though hospitalisations have yet to reach the heights seen in previous waves, pointing to the persistently high immunity levels in the UK.

Nonetheless, said Prof Robertson, “even if [the two sub-variants] are only slightly worse, this could be a problem if there’s large number of infections occurring, particularly for the more vulnerable groups”.

The ZOE Covid Study estimates that case rates in the UK “will continue to rise for the next week or so” – fuelled by the spread of BA.5 and the festival season, which is bringing together hundreds of thousands of people in close proximity.

Prof Spector said daily infections could even run close to 350,000 – an estimated record for the pandemic that was reached in late March 2022.

Separate data from the UK Health Security Agency shows a rise in Covid case rates among all age groups and regions in England, with increases most acute in those aged over 80.

Admissions to intensive care are also climbing among the elderly, and more outbreaks are now being reported in care homes, UKHSA said.

Around one in six people aged 75 and over have not received a vaccine dose within the past six months, putting them more at risk of severe disease, the health agency warned.

In total, some 8,928 hospital patients in England had Covid-19 on 30 June, up 39 per cent on the previous week, data shows. This is just over half the level of patients recorded at the peak of the Omicron BA.2 wave.

UKHSA chief executive, Dame Jenny Harries, on Sunday warned hospital cases are expected to rise further and raised concerns about the NHS’ ability to treat other illnesses as a result.

She told the BBC’s Sunday Morning programme: “It doesn’t look as though that wave has finished yet, so we would anticipate that hospital cases will rise. And it’s possible, quite likely, that they will actually peak over the previous BA.2 wave.”

“Whilst we have an armament now of vaccines and antiviral treatments, we do have, as you’ve just highlighted, a rise in hospital admissions and occupancy,” she said.

“And that means it’s not just Covid that we’re concerned about, but it’s actually our ability to treat other illnesses as well.”

Aris Katzourakis, a professor of evolution and genomics at the University of Oxford, said the ever-increasing infection levels would only help to further drive the continuing evolution of the Covid virus.

“Moreover, over time, circulating variants will become more and more distant from the original strain that is used in our vaccines,” he said. “Thus, unless our vaccines are updated, there may come a point where protection against severe disease is further diminished.”

Professor Kei Sato, a virologist at the University of Tokyo whose research showed that the BA.4 and BA.5 could cause more serious infections than the original Omicron variant, said it “might be the time” to start rolling out updated vaccines.

However, he warned, there could be a sudden and unexpected shift in the genetic make-up of the virus – akin to the stark jump that was seen between the Alpha, Beta, Delta and Omicron variants – which could undermine the effectiveness of any new vaccine.

Not all are convinced that the vaccines should be updated, while others are unsure how they should be altered. Professor Deenan Pillay, a virologist a University College London, said “we need to see what immunity updated vaccines confer”.

More data is expected from Moderna as it studies the effectiveness of its bivalent vaccine. This will demonstrate how it fares in reducing hospitalisations and case rates. These will likely be reviewed by the government’s vaccine watchdog as it plans for the autumn booster programme.

Dr David Strain, a senior clinical lecturer at the University of Exeter Medical School, said an “additional benefit” of the new Moderna jab was “that it focused on core [viral] elements that had been common between the original and Omicron variants, and therefore is more likely to protect us against future variants.”

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