Will booster jabs REALLY beat Omicron?

ALL major Covid vaccines are ‘markedly’ weaker at preventing Omicron infection — even boosters — lab trial suggests, but Chris Whitty claims three doses could protect against severe illness BETTER than two did against Delta

  • Study found antibody levels after booster are 6.5 times lower against Omicron compared to the original virus
  • But England’s chief medical officer said third jabs could give more protection than two doses against Delta
  • And experts said Omicron hospitalisations should be lower than previous waves due to immune response

The Omicron Covid variant makes all major vaccines ‘markedly’ weaker at preventing infection after two doses, another lab study has found.

Columbia University researchers tested the mutant strain against the blood of people vaccinated with two doses of the four big brands — Pfizer, Moderna, Johnson & Johnson and AstraZeneca.

They also looked at people given a booster of one of the two mRNA vaccines as part of their study, which has not been peer-reviewed or published in a scientific journal.

There was a 21-fold drop in neutralising antibodies against Omicron after two doses of Pfizer compared to the original strain and a 8.6-fold drop with Moderna’s jabs.  

Antibodies were so low two-dose course of Johnson & Johnson and AstraZeneca’s jabs that they were undetectable, suggesting they offer virtually no protection against infection. 

But scientists caution that antibody studies are a very narrow view of the immune response to Covid as they don’t account for T cell and B cells, which are key for preventing severe symptoms but harder to measure.

And experts told MailOnline other parts of the immune system response to the virus, due to vaccination or an earlier infection, should hold up against Omicron and keep hospitalisations below the levels seen in previous waves. 

Patients given a booster jab of either Pfizer or Moderna had 6.5 times fewer antibodies for Omicron than the original virus.

America’s top Covid doctor Anthony Fauci insisted booster shots will still offer extremely high protection against hospitalisation and death from Omicron.

England’s chief medical officer Professor Chris Whitty yesterday said booster jabs could leave Britons better protected against Omicron than they were after two doses against the Delta strain, which was dominant in Britain until this week. 

Data in the UK and South Africa suggests that even in people given two doses of Pfizer’s vaccine six months ago, they should still get 70 per cent protection against severe Omicron disease.

Columbia researchers found that all four major Covid vaccines, (L-R) Pfizer, Moderna, Johnson & Johnson and AstraZeneca, failed to consistently provide adequate protection against the Omicron variant on their own. People jabbed with Pfizer produced 21 times less antibodies against Omicron, while protection from Moderna fell nine-fold. And neutralising antibodies from AstraZeneca and Johnson & Johnson were almost indetectable. People who had been triple-jabbed (far right graph) with Pfizer and Moderna showed a 6.5-fold drop in neutralising antibodies against Omicron, compared to the levels recorded when their blood was exposed to the Wuhan strain

A separate study by researchers at the Ragon Institute of MGH, MIT and Harvard also found two doses of vaccine are less effective against Omicron. However, their study showed third doses bring neutralising antibodies back to the level they were against the Delta variant. The graphs show neutralising antibody levels against the original version of Covid compared to Delta (left) and Omicron (right). The dotted black line shows antibody levels after two jabs, while the solid black line shows antibody protection after three jabs. The booster line is much steep against Omicron, meaning that third doses there is higher protection after three jabs, the researchers said

Professor James Naismith, director of national research centre the Rosalind Franklin Institute, who was not involved in the study, told MailOnline the study results echo other findings on Omicron and ‘should be taken seriously’, but antibodies are just part of the body’s response to a Covid infection. 

He said: ‘Omicron is extremely good at evading the antibody response.  

‘People without a booster are likely to be infected by Omicron if they are exposed to it because of its evasion. Case numbers will get very high very quickly.’

But antibody response is ‘not all or nothing, a 10 nil win is just as a good as 1 nil win in extra time’, Professor Naismith said.

Omicron-hotspot London’s Covid wave is soaring in EVERY age group except children

Covid cases are now rising in every age group except young children in Omicron-hotspot London, according to official figures that lay bare the threat the NHS faces in the coming weeks.

The super-mutant variant, which is already dominant in the capital, has effectively sent the city of 10million into its own lockdown, with tens of thousands of workers staying at home today to avoid isolating over Christmas.

Department of Health data shows London is now seeing just as many cases as last January, when it was battered by the Alpha variant and put under harsher measures than the rest of the country.

London’s spiralling crisis was initially driven by teenagers and adults in their 20s, 30s and 40s, who were seeing an uptick in cases two weeks before the ultra-infectious strain was first detected. 

Infections started to rise in the over-60s days after Omicron was confirmed to be in Britain, according to MailOnline analysis. 

In another warning sign for the country, UK Health Security Agency data published today revealed the capital now has the 25 areas with the fastest growing outbreaks in England. 

Experts have admitted the capital’s crisis will inevitably slow down because the virus will simply run out of room, and people adhere to dire warnings from Boris Johnson and Professor Chris Whitty’s plea to ‘prioritise’ the most important social events in the coming days.

‘The higher level of antibodies in boosted people does give improved protection against infection, think the booster as a super sub,’ he said. 

And people have innate immunity as well as a T-cell response from vaccination or previous infection, which offer protection, Professor Naismith said.

He added: ‘What is as yet unknown is how many hospitalisations will result from 1,000 Omicron infections in the UK. 

‘I am sure it to be much less than the first wave and I very much hope it will be significantly less than Delta.’

Clear-cut evidence of the efficacy of boosters on the super-mutant variant in the UK is due within a fortnight. 

The UK Health Security Agency says there needs to be 250 patients in hospital with Omicron before it can make estimates on vaccine effectiveness. 

Just 16 Britons have been hospitalised with the variant in the UK so far, but this is thought to be an underestimate because not all positive tests are analysed for variants. 

It comes as the UK’s daily Covid cases yesterday soared to their highest level for the second year in a row, with 88,376 positive tests reported. On Wednesday, 78,610 cases were identified. The previous high was 68,053, which was recorded in January.

A turbo-charged booster programme is dishing out third doses in a bid to limit the impact of the Omicron wave, with 745,183 administered yesterday, the most third doses in a single day. 

Top scientists say the top-up jabs will increase protection against severe illness, hospitalisation and death caused by the mutant strain, but the jabs are expected to have a limited impact on transmissibility.  

The Colombia researchers said blood samples showed Omicron triggered 32 times less neutralising antibodies compared to the original virus strain.  

Even blood samples from people boosted with Pfizer or Moderna — the vaccines being used for third doses in the UK — showed the vaccines had ‘diminished’ neutralising activity against Omicron. 

And people who had been triple-jabbed with Pfizer and Moderna showed a 6.5-fold drop in neutralising antibodies against Omicron, compared to the levels recorded when their blood was exposed to the Wuhan strain. 

The team also evaluated monoclonal antibody treatments and found their effectiveness was ‘abolished or impaired’ against the variant.

This finding means the treatments already approved in the UK, such as Ronapreve, could be much less effective. GSK claim their new antibody treatment, called sotrovimab, should still be highly effective against Omicron, but this has yet to be shown.  

The Columbia University researchers said four of Omicron’s spike mutations — S371L, N440K, G446S, and Q493R — make it better at resisting antibody protection. 

But it has a total of 32 mutations on its spike protein alone, many of which have been described as unusual and scientists are probing what effect they may have on immunity.  

‘The Omicron variant presents a serious threat to many existing Covid vaccines and therapies,’ the researchers warned.    

Speaking to MPs on the Health and Social Care Committee, Professor Whitty said the best case scenario is that six per cent of over-65s who get infected with Omicron are hospitalised, the same rate as Delta. 

For comparison, in the first and second waves when there were no vaccines, the hospitalisation rate among infected people in that age group was 22 per cent.

‘But it is possible that with a boost we are better off with Omicron than we are with two vaccines with Delta for severe disease,’ Professor Whitty said.

Professor Whitty warns jab that frees Britain from endless cycle of restrictions won’t be ready until mid-2023

Britain can expect another 18 months of potential Covid misery until a vaccine that protects against all variants is developed and rolled out, Chris Whitty warned today.

The chief medical officer said he expects a universal jab that can fight multiple strains to be ready at some point in mid-2023 as well as several new antiviral drugs, which should do the ‘heavy lifting’ for the NHS.

But he admitted that in the meantime, ministers will have to rely on social restrictions when vaccine-resistant variants like Omicron threaten to overwhelm the health service.

Speaking to MPs on the Health and Social Care Select Committee, Professor Whitty said: ‘If I project forward, I would anticipate in a number of years, possibly 18 months, possibly slightly less… we will have polyvalent vaccines which will cover a much wider range [of variants].

‘And we will probably have several antivirals… and a variety of other countermeasures that mean that the great majority, and probably almost all of the heavy lifting, when we get a new variant, unless it is extremely different, can be met by medical means.’

Vaccine makers have been quietly working on as polyvalent Covid jabs, designed to immunise against multiple strains, but they are all in early development and way off clinical trials.

Professor Whitty’s 18-month timeline is more optimistic than many scientific advisers. Nervtag, a subcommittee that feeds into SAGE, last week warned in advice to ministers that Covid would pose a threat to the NHS for at least five years. 

Dr Susan Hopkins, head of the UK Health Security Agency (UKHSA), told MPs on the same committee that 250 Britons would need to be hospitalised with Omicron for scientists to estimate how severe the strain is and how effective vaccines are against it.

There are 16 people hospitalised with the variant, but Professor Whitty warned the true figure will be ‘much bigger’, as not all positive tests among patients have been sequenced to determine which variant they are infected with.   

Researchers at the Ragon Institute of MGH, MIT and Harvard also found two doses of vaccine are less effective against Omicron. 

However, their study showed third doses bring neutralising antibodies back to the level they were against the Delta variant.

Top US expert Professor Carl Bergstrom, a biologist at the University of Washington, said the study shows boosters have a ‘much greater impact on protection against Omicron’ than they offer against earlier strains of the virus.

‘That suggests that the booster does not merely increase antibody titres, but that it changes those antibodies in ways that better target Omicron,’ he said. 

And data from the UK Government last week revealed booster jabs offer up to 75 protection against mild illness caused by Omicron. 

The real-world analysis by the UKHSA looked at 581 people with confirmed Omicron and compared their vaccine status to a control group of people who tested positive for Delta.

It estimated that a Pfizer booster provides between 70 and 75 per cent protection against mild Omicron illness, regardless of which vaccine was originally used, compared to 90 per cent for Delta.

Two doses of Pfizer may offer just 37 per cent protection after three-and-a-half months compared to 60 per cent for Delta. Two shots of AstraZeneca offered virtually no protection after the same amount of time.

But the scientists caution that data for AstraZeneca was less reliable due to the fact the vaccine was restricted in some age groups and typically used at the very start of the initial vaccine rollout in vulnerable people.   

And early data from South Africa, the epicentre of the Omicron outbreak, suggests the variant is causing up to a third fewer hospitalisations than Delta, while two Covid jabs do appear to cut the risk of hospitalisation. 

Officials who analysed 78,000 Omicron cases in the past month estimated the risk of hospitalisation was a fifth lower than with Delta and 29 per cent lower than the original virus.

As a crude rate, Omicron is currently leading to a third fewer hospital admissions than Delta did during its entire wave — 38 admissions per 1,000 Omicron cases compared to 101 per 1,000 for Delta.

The researchers also found two doses of Pfizer’s vaccine still provide 70 per cent protection against hospital admission or death from Omicron, compared to 93 per cent for Delta.

While this is more protection than many scientists initially feared, it still leaves 30 per cent of people vulnerable to severe Omicron disease, four times as many as Delta.

WHAT DOES THE LAB EVIDENCE SHOW ABOUT VACCINE EFFECTIVENESS AGAINST OMICRON? 

1. South Africa

People vaccinated with Pfizer have 40 times less antibodies that can fight against Omicron compared to other variants, according to one lab-based study.

Researchers at the African Health Research Institute (AHRI) took blood samples from 12 people double-jabbed with Pfizer. 

They examined levels of neutralising antibodies that can prevent infection from Omicron. 

The researchers found there is a 40-fold decrease in antibodies that fight against the strain, compared to the number that can defend against other variants.

The study only looked at antibodies, which are just one part of the immune response that fights off the virus. Although they are normally a reliable indicator. 

It is not clear that this will translate into lower protection against severe illness, hospitalisation and death among those who catch the strain. 

The researchers also found that Omicron still uses the ACE2 receptor on cells to infect people.

Professor Alex Sigal, a virologist at the AHRI who led the study, said this means the variant can be managed with the vaccines we have.

2. Sweden

A separate study by researchers in Sweden found that while there is a drop in the body’s ability to neutralise Omicron it is not seen in everyone and is a smaller drop than feared.

Scientists at the Karolinska Institute in Stockholm found there was an average seven-fold drop in neutralisation potency against Omicron.

But it varied between a 1-fold and 23-fold reduction among patients. 

Researchers said almost all blood samples evaluated had some form of neutralising antibody response against Omicron.

Their findings were based on recent blood samples from 17 people in Stockholm, compared to 17 hospital workers who were previously infected with the original Wuhan strain. 

Benjamin Murrell, an assistant professor in computational biology, virology and immunology and one of the researchers behind the study, said this is ‘certainly worse than Delta’ but is not ‘as extreme as we expected’. 

He said the AHRI study reported a ‘much more substantial average reduction’ but noted ‘what is common is that neutralisation is not completely lost for all samples, which is positive’. 

3. Germany

A third set of results shared by researchers in Germany found neutralising antibodies from two doses of the vaccines used in the UK are ineffective against the strain. 

Dr Sandra Ciesek, a virologist at the German Center for Infection Research, tweeted laboratory findings, which have not yet been published, show that six months after two doses of Pfizer or Moderna, or a first dose of AstraZeneca and second dose of Pfizer, there was no neutralising antibodies present that could protect against Omicron. 

And even three months after being boosted with the Pfizer jab, people had just 25 per cent protection from neutralising antibodies against Omicron, compared to 95 per cent protection at the same point against Delta. 

Dr Ciesek said this translates into a 37-fold reduction against Omicron compared to the Delta strain. 

The findings confirm that developing new vaccines that target Omicron ‘makes sense’, she said.

But Dr Ciesek noted that the results ‘cannot say anything’ about whether people are still protected from severe illness, which other parts of the immune system play a key part in warding off. 

4. Pfizer

Pfizer’s results are based on a laboratory study using the blood of 20 people, who were either double-jabbed three weeks earlier or triple-jabbed one month earlier with its vaccine.

The results showed the third dose may provide a ‘more robust protection’, triggering a 25-fold jump in antibody levels. 

Pfizer, which manufactured the jab with German partner firm BioNTech, said the levels equated to a ‘high efficacy’ based on data against other variants. 

A booster jab offered a boost in antibody levels that are ‘comparable to those observed’ for the original Wuhan virus after two doses, the company said.

The level of neutralising antibodies against Omicron after three jabs was 154, compared to 155 against the Wuhan strain after two jabs.

But the figure was 60 per cent lower than levels seen for three doses against Delta.

5. US

A study by researchers at Colombia University , which is a pre-print and has not yet been peer-reviewed, said blood samples showed Omicron triggered 32 times less neutralising antibodies compared to the original virus strain. 

Meanwhile, people jabbed with Pfizer produced 21 times less antibodies against Omicron, while protection from Moderna fell nine-fold. 

And neutralising antibodies from AstraZeneca and Johnson & Johnson were almost indetectable. 

Even blood samples from people boosted with Pfizer or Moderna — the vaccines being used for third doses in the UK — showed the vaccines had ‘diminished’ neutralising activity against Omicron. 

And people who had been triple-jabbed with Pfizer and Moderna showed a 6.5-fold drop in neutralising antibodies against Omicron, compared to the levels recorded when their blood was exposed to the Wuhan strain. 

 

 

Source: Read Full Article