WHO says Omicron is no worse than other variants and jabs should work against it

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Pfizer‘s Covid booster vaccine triggers a 25-fold spike in antibody levels against Omicron, the drug firm claimed today as it admitted two doses may not be enough to thwart the mutant strain.

The vaccine manufacturer argued three injections provide a ‘more robust’ defence against the variant, which has caused chaos since it was first identified in South Africa last month.

A third dose triggers a similar antibody response against Omicron to two doses against previous strains of Covid, according to preliminary laboratory tests. It also ‘strongly increases’ T cell levels, offering the immune system an extra boost to protect against severe disease. 

But Pfizer also insisted that two doses should still be enough to slash rates of hospitalisations and deaths, in the event of fresh waves triggered by the super-mutant strain.

It comes as two separate studies released today show that vaccines appear to work better than expected against Omicron, which is quickly spiralling in Britain and has left No10 on the brink of resorting to its ‘Plan B’ to save the NHS from being overwhelmed this winter.

A research institute in South Africa found people fully-vaccinated with Pfizer’s jab make 40-times fewer antibodies against Omicron compared to other variants. But the lead author of the research, the first of four laboratory-based studies released in the last 24 hours, insisted the results are ‘better than expected’.

Another study by Swedish virologists found that while there is a drop in the body’s ability to neutralise Omicron after jabs, this decline is not seen in everyone and is a smaller fall than feared.

Meanwhile, a World Health Organization official said Omicron appears to be less severe than other Covid variants.

Dr Michael Ryan, the WHO’s emergencies director, said despite likely being more transmissible than other variants, early data suggests Omicron is less severe than other strains.

And vaccines should protect against severe illness and hospitalisation, as they have done for previous worrying variants, such as Beta and Delta, Dr Ryan said. 

Even if it causes milder illness than other strains, if a large proportion of the population catch the virus, it could put the NHS under severe pressure if hospitalisations trend upwards. 

But a third set of lab results from Germany found that double-jabbed people may not produce any neutralising antibodies against Omicron, and even once boosted the vaccines are 37 times less effective against the new strain than Delta.

However, it is unclear whether this reduced antibody response will have an effect on serious illness, hospitalisations and deaths, as other parts of the immune system, such as T cells, are considered key in suppressing severe outcomes. 

UK officials hope the booster rollout to all adults — which Boris Johnson pledged to deliver by the end of January — will increase protection against the strain, which experts believe will be dominant by Christmas.

The Prime Minister yesterday acknowledged Omicron appears to be more transmissible. 

Professor Neil Ferguson, an epidemiologist at Imperial College London and Government scientists, this morning said a lockdown could be imposed if the NHS is overwhelmed.

Pfizer’s results are based on a laboratory study using the blood of people triple-jabbed one month earlier with its vaccine, which is tested against the Omicron variant.

The results showed athird dose may provide a ‘more robust protection’ by triggering a 25-fold increase in antibody levels, it said, which equates to a ‘high efficacy’ against all variants. 

The booster jab neutralised the Omicron variant ‘to 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.

The figure is still a huge drop compared to antibody levels against Delta, which stand at 398 after three doses. 

A drop in antibody levels doesn’t translate into vaccine efficacy, but instead gives an indicator.

Pfizer said booster injections also increase CD8+ T cells, which are linked with protection against severe disease. 

The company will collect data on whether the antibodies remain at that level in the months after a booster dose. 

Meanwhile, blood samples for people who were only double-jabbed had a 25-fold reduction in their antibody levels against Omicron compared to the original strain.

This indicates two doses of the Pfizer injection ‘may not be sufficient to protect against infection with the Omicron variant’, the company admitted.  

However, despite Omicron’s extensive mutations, Pfizer believes two jabs will protect people against severe forms of disease and are monitoring its real-world effectiveness to confirm this. 

Albert Bourla, chair and chief executive officer at Pfizer, said: ‘Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine.

‘Ensuring as many people as possible are fully vaccinated with the first two dose series and a booster remains the best course of action to prevent the spread of Covid.’

Ugur Sahin, chief executive officer and co-founder of BioNTech, said: ‘Broad vaccination and booster campaigns around the world could help us to better protect people everywhere and to get through the winter season. 

‘We continue to work on an adapted vaccine which, we believe, will help to induce a high level of protection against Omicron-induced Covid disease as well as a prolonged protection compared to the current vaccine.’

Pfizer began developing a Covid vaccine on November 25 that is targeted at the Omicron variant, which it can dish out from March 2022 if the current crop of jabs are not providing sufficient protection. 

Some 437 Omicron cases have been spotted in the UK since the virus was first identified in South Africa.

The Government has reintroduced mandatory face covering rules, added 11 countries to the red list and imposed tighter restrictions for UK arrivals in a bid to control the spread of the variant. 

WHO official Dr Ryan today said the strain is likely more transmissible than previous variants, but is ‘highly unlikely’ to completely evade vaccine protections.

He said: ‘The preliminary data doesn’t indicate that this is more severe. In fact, if anything, the direction is towards less severity.’  

The WHO official said there was no sign that Omicron could fully sidestep protections provided by existing Covid vaccines.

‘We have highly effective vaccines that have proved effective against all the variants so far, in terms of severe disease and hospitalisation… There’s no reason to expect that it wouldn’t be so’ for Omicron, he added, pointing to initial data from South Africa, where the strain was first reported.

However, Dr Ryan acknowledged that it was possible that existing vaccines might prove less effective against Omicron, which counts more than 30 mutations on the spike protein that dots the surface of the coronavirus and allows it to invade cells.

It comes after researchers at the African Health Research Institute (AHRI) found people who received the Pfizer vaccine have 40-times less antibodies that can defend against Omicron. 

The scientists examined blood samples from 12 people double-jabbed from Pfizer who had not yet received their booster.

The pre-print study, which is yet to be peer-reviewed, found Omicron’s mutation seemed to enable it to dodge many of the vaccine-triggered antibodies. 

However, 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. 

And those most vulnerable to Covid are eligible for a third shot in the UK, which experts hope will boost the protection compared to having just two doses. 

It is not clear whether the reduced number of antibodies will translate into lower protection against severe illness, hospitalisation and death among those who catch the strain.

Professor Alex Sigal, a virologist at the AHRI who led the study, tweeted that the results of the study are ‘better than I expected of Omicron’.

He noted there is a ‘very large drop’ in protection from Pfizer compared to other variants, but those who previously had Covid and are vaccinated were more protected against the variant. 

Professor Daniel Altmann, an immunologist at Imperial College London, said the study offers a ‘clear message’ that those who are unvaccinated or double-jabbed ‘are likely to be highly vulnerable to infection’. 

‘However, those who’ve seen spike three times, either by boosting or by infection plus two doses, appear generally in the safety zone, even with a 41-fold drop,’ he said. 

The study provides ‘an even stronger argument for getting boosters as widely and rapidly as possible’, Professor Altmann said.

And Professor Penny Ward, an expert in pharmaceutical medicine at King’s College London, said it is ‘not surprising’ that higher levels of antibodies are needed to neutralise Omicron compared to other strains due to its ‘complex series of mutations’.

She noted that when scientists looked at other strains in the laboratory they found similar reductions in vaccine effectiveness, but this did not lead to a real-world drop in protection against severe illness. 

‘After a year’s experience with the covid vaccines, we know that lower levels of antibody, while being less effective at preventing infection, remain very highly effective at reducing hospitalisation and mortality rates,’ Professor Ward added.

And Professor Jonathan Ball, a virologist at the University of Nottingham, noted that while ‘the amount of virus killing observed in the lab is reduced markedly – up to 40-times reduction – there is still measurable virus neutralisation, especially in those who were vaccinated and previously infected.’

‘This group effectively mimics what we would expect in people who had had two doses of vaccine plus a boost,’ he said.

Professor Ball added: ‘Whilst we do not fully understand what protective immunity looks like, the data should give us reassurance that the vaccine will still offer protection.

‘The other thing to remember is that many of the vaccines also generate T cell immunity and we think that this will be less impacted by the high level of mutations that omicron has.

‘Whilst this reduced antibody immunity might mean more people can be infected and have mild symptoms, I am still confident that the vaccines, especially after a boost, will still protect from serious disease. 

‘That’s why we still need to get the message across, get vaccinated, get boosted, even if you have been infected before.’ 

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

Scientists at the Karolinska Institutet in Stockholm found there was an average seven-fold drop in neutralisation potency among 17 blood donors.

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 Professor Sigal’s 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’. 

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. 

Professor Francois Balloux, a geneticist at University College London, said results from the different neutralisation studies are difficult to compare and it is too early to know why the results from the German study ‘look so much worse’. 

‘Whatever the reason, those results do not suggest that neutralising antibody activity can be restored by a third dose,’ he said.

‘Those results suggests that a large proportion of the population globally is at risk of (re-)infection by the omicron variant over the coming months,’ Professor Balloux said. 

But he noted milder symptoms have so far been recorded among those infected with Omicron.

And real-world data suggests vaccines are still protecting against severe illness through other antibodies and T cells, Professor Balloux added.

Top US scientist Anthony Fauci echoed the WHO’s view, saying Omicron did not appear worse than prior strains based on early indications – and was possibly milder.

The new variant is ‘clearly highly transmissible,’ very likely more so than Delta, the current dominant global strain, Fauci told AFP.

‘It almost certainly is not more severe than Delta,’ he added. ‘There is some suggestion that it might even be less severe.’

But he noted it was important to not over-interpret this data because the populations being followed skewed young and were less likely to become hospitalised. Severe disease can also take weeks to develop.

‘Then as we get more infections throughout the rest of the world, it might take longer to see what’s the level of severity.’ 

It comes as UK daily Covid infections jumped 15 per cent in a week to 45,691, with scientists estimating Omicron cases are doubling every two days. 

‘Professor Lockdown‘ Neil Ferguson today admitted that another nationwide shutdown could be on the cards to tackle Omicron. 

The Government scientist, whose modelling bounced No10 into the original lockdown last spring, said the return of stay-at-home orders ‘certainly might be possible’ if the mutant strain threatens to overwhelm the NHS. 

He told the BBC Radio 4 Today programme: ‘There is a rationale, just epidemiologically, to try and slow this down, to buy us more time principally to get boosters into people’s arms because we do think people who are boosted will have the best level of protection possible, but also to buy us more time to really better characterise the threat.’

Asked outright if a lockdown could be reimposed, he said: ‘Clearly if the consensus is it’s highly likely that the NHS is overwhelmed then it will be for the Government to decide what to do about that but it’s a difficult situation to be in of course. It certainly might be possible at the current time.’

Only 8% of hospitalised Covid patients in South Africa’s Omicron ground zero now get admitted to ICU which is just a THIRD of level seen during Delta wave, fuelling hopes that the super-mutant variant IS milder

EXCLUSIVE: Official figures show 139 patients were in ICU in South Africa’s epicentre Gauteng on MondayFor comparison, at the same point in the Delta wave the province had 393 patients in the emergency wardsBritish experts said immunity from vaccines and past infection was likely holding up against OmicronThey also did not rule out the possibility that the mutant strain could be less virulent than first feared ByLuke Andrews Health Reporter For Mailonline

Published: 07:58 EST, 8 December 2021 | Updated: 09:18 EST, 8 December 2021

Intensive care rates among hospitalised Covid patients in South Africa are now running at just a third of the level they were at the same point in the country’s Delta wave, official figures suggest amid hopes Omicron has evolved to be milder. 

In Gauteng province, the super-mutant variant’s ‘ground zero’, 139 Covid patients in hospital were being cared for in intensive care wards on Monday, about two weeks into the nation’s latest wave. This was the equivalent to 8 per cent of all infected patients who were admitted for treatment. 

For comparison, there were 393 infected patients in ICUs in the two weeks after Delta took off in the province, or 24 per cent.

Experts have warned the raw number of admissions and ICU patients could still overtake the levels seen during the Delta wave in June because of how long it takes for infections to translate into serious illness. 

But British scientists told MailOnline the promising data, from the Government’s National Institute for Communicable Diseases, offered evidence that the variant could be milder than other mutant strains.

It also backed up claims from South African doctors on the frontlines who say fewer Covid-infected patients need ventilators than was the case when Delta took hold. Other real-world data from Norway and the UK also suggests the mutant strain may be less lethal than its rivals.

Some experts have speculated the virus may have evolved to become less severe over time, but others question if it is merely the result of very high levels of natural immunity in South Africa after the Delta wave.

Up to 80 per cent of South Africans are believed to have had Covid now and recent infection helps keep reinfection cases mild.

The finding offers hope that the UK’s Omicron wave could be less severe than past peaks. But scientists warn the mutant strain will pile pressure on the NHS if it is more transmissible because of the sheer number of people who will catch it.

Data already suggests the mutant strain is more transmissible than Delta, and Boris Johnson yesterday told his Cabinet that ‘early indications’ are that it is more contagious. Its rapid spread across the UK has sparked fresh concerns that more curbs could be introduced before Christmas.  

No10 officials have insisted the Government will act ‘swiftly’ to contain the variant if necessary, and have drawn up plans to ask people in England to ‘work from home’.

Top experts said cases were doubling around every two to three days and the strain would be dominant in weeks, and possibly ‘before Christmas’. It has now been spotted 437 times in Britain, but that is just a fraction of the true toll.

It comes after a South African study found antibodies in 12 patients who were double-vaccinated with Pfizer had 40 times less antibodies against the mutant strain than older variants. But antibodies are just one part of the overall immune response to Covid, with B and T cells also playing a crucial role.

South Africa’s NICD publishes daily reports on the number of Covid patients in hospitals by provinces, and the number that are in ICU or on ventilators.

In Gauteng, where the country’s largest city Johannesburg is based, the number of infected patients in hospital has jumped 65.3 per cent week-on-week.

But separate data bolstering the case that it is a milder strain suggest that just 25 per cent are being treated for the actual illness, with others just incidentally testing positive after being admitted for something else.

NICD figures showed that in the latest week — roughly a fortnight after the strain was first detected — there were 1,371 Covid-infected patients in the province’s hospitals every day, on average.

Some 103 of these were in intensive care facilities (eight per cent), and 30 were hooked up to ventilators (two per cent).

For comparison, in the second week of the Delta wave there were 1,578 patients in hospital every day with 380 in the ICU (24 per cent) and 153 on ventilators (10 per cent).

But the rates now appear to be ticking up despite staying at about a third of the levels seen in the Delta wave for more than a week.

Yesterday of the 1,805 Covid patients in hospital in the region 177 were in the ICU (9.8 per cent) and 51 were on ventilators (2.8 per cent). 

The start of South Africa’s Omicron and Delta waves were chosen based on when the country announced it had detected its first case of each variant. 

For Delta, this was May 8, while the first case of Omicron was announced on November 25.  

At the start of the Delta wave, the infection rate across South Africa almost doubled in a fortnight from 23.3 cases per million people to 44.2.

For comparison, when Omicron first took off daily infections surged by almost 2,000 per cent from 9.1 to 177 cases per million.

The Omicron wave kicked off when infections were at a much lower point than the Delta wave. 

The South African Government also only began to count positive lateral flow tests in its official figures from mid-November, which may have skewed the comparison.

It is not clear how many hospitalisations in the province were triggered by Omicron, but experts say it is likely to be at least the majority because the variant is now dominant in the area. 

Three of South Africa’s neighbours — Zimbabwe, Namibia and Eswatini — are now seeing their cases start to rise as the variant takes hold in the region. 

For Zimbabwe, which shares a 140-mile border with South Africa, its infection rate has risen more than 700 per cent in a week from 5.22 cases per million people to 45.6.

In Namibia infections are also up more than 700 per cent from 4.1 to 34 cases per million people. And in Eswatini,   a tiny nation landlocked by South Africa and Mozambique, the infection rate has rocketed 1,300 per cent from 11 to 154 cases per million.

Genomic sequencing in the countries is poor, meaning it is not clear how much Omicron is to blame for their outbreaks. But experts have said it was likely to be responsible for the uptick in all three of the countries. 

Professor Francois Balloux, a geneticist at University College London, said it was possible that the variant is less virulent than first feared based on the figures.

He told MailOnline: ‘Hospitalisations may indeed be lower than during earlier waves because a larger proportion of the population in South Africa has now acquired immunity through prior infection and/or vaccination or because Omicron itself is less virulent than Delta, or a bit of both.

‘This view is solely based on Gauteng data so far.’

Professor Paul Hunter, an infectious diseases expert at the University of East Anglia, agreed that it was possible the mutant strain could be less virulent than Delta.

‘It is quite possible,’ he told MailOnline. ‘But what I would say is you often don’t end up on ventilators until two or three weeks after infection. 

‘So it is still too early to be definite, but there are early signs in the data that this may be the case.’

He added that at a WHO meeting this week, data was revealed that showed patients in all age groups were about a third as likely to suffer severe disease as those who caught Delta.

But again, many are still facing a relatively early illness which could get worse over time. 

Professor Hunter warned even if it was less virulent the fact it is more transmissible means it could still lead to as many hospitalisations as Delta.

He said: ‘If there is a 50 per cent reduction in virulence but it is four times more transmissible, then you get double the number of people severely ill.’ 

Dr Jeffrey Barrett, who heads up variant sequencing at one of Britain’s largest surveillance centres, at the Sanger Institute, said the figures could be down to higher immunity levels now than when Delta first spread.

He told MailOnline: ‘If people with prior infection had no immunity to infection from Omicron, but high immunity from hospitalisation, then in a country like South Africa you’d see exactly what we’re seeing now.

‘Lots of infections, including reinfections, but a lower proportion of severe disease.’

He added: ‘We need to see carefully matched datasets comparing Delta and Omicron hospitalisation conditional on vaccine status, prior infection, age, and so on. That will probably happen in three to four weeks time.’

Some 24 per cent of people in the country are vaccinated against Covid, but most are already thought to have some immunity against the virus from previous infection.

A study carried out in February found half of almost 5,000 people tested had Covid antibodies. Since then the country has been hit by the more transmissible Delta wave.

Some scientists have suggested that the virus may become less virulent over time as it adapts to living in humans.

Dr Tine Ravlo, a public health expert in the Norwegian capital involved in tracking the outbreak, said that so far ‘none have become severely ill and none of them have been treated in hospital’. 

But critics of the theory, which has circulated ever since Alpha was detected last year, warn there is no evidence that this will happen and that it could in fact become more dangerous. 

South African doctors say they have noticed a ‘high number’ of Covid patients that are on ‘room air’, rather than being hooked up to ventilators.

Dr Fareed Abdullah, an infectious disease doctor at Steve Biko hospital in Gauteng, told the Financial Times: ‘You walked into a Covid ward any time in the past 18 months… you could hear the oxygen whooshing out of the wall sockets, you could hear the ventilators beeping.

‘But now the vast majority of patients are like any other ward.’

South Africa’s Covid cases yesterday tripled week-on-week after another 13,147 infections were recorded, and hospitalisations more than doubled with another 383 admissions reported.

In Britain 437 Omicron cases have been detected to date. But there are yet to be any hospitalisations or deaths associated with the mutant strain.

It comes after top epidemiologist Professor Spector claimed the highly evolved variant was already taking hold in Britain.

The King’s College London scientist, who runs the country’s largest symptom-tracking study, estimated that in 10 days’ time Britain will have more Omicron cases than most African countries at the epicentre of the new outbreak, meaning there would be ‘very little point’ in having travel restrictions.

No10 yesterday warned the variant is now spreading domestically in multiple regions, with the official count now standing at 336 although none of those infected with it have been hospitalised. Separate data shows the strain is thought to make up one in 60 of all new cases.

Dominic Raab today claimed that ministers were not looking to bring in tougher Christmas curbs, working from home or vaccine passports, despite the sharp uptick in Omicron. ‘We don’t think Plan B is required,’ he told BBC Radio 4’s Today programme. ‘Why? Because of the success of the vaccine programme.’

Mr Raab was more definitive than Boris Johnson who yesterday refused to rule out tightening restrictions over the festive period, merely insisting that Christmas will be ‘better’ than last year.

Scientists expect booster jabs to give high protection against severe illness and death from Omicron, even if the variant makes vaccines much less effective at preventing infection.