Experts warn dishing out fourth jabs in spring may be pointless

View
comments

Britain, the US and other major economies could be on the brink of over-vaccinating people in the fight against Covid, experts say.

Israeli officials have already announced their intentions to embark on dishing out another round of booster jabs, meaning both the UK and US will eventually face pressure to follow suit even though both nations have insisted there are no plans to administer fourth doses yet.

But scientists argue that rolling out vaccines every three-to-four months simply isn’t ‘doable’ and may not even be necessary because of Omicron, which some believe will speed up the process of endemicity and consign days of sky-high hospitalisation and death figures to history. 

And they called for more data on dosing gaps between boosters before pressing ahead with plans to administer fourth jabs. Some experts claim the benefits of extra jabs are minimal because their primary purpose – preventing deaths and hospitalisations – has barely waned after a year and several Covid variants, effectively meaning boosters are adding to an already high base level immunity.   

Professor Ian Jones, a virologist at the University of Reading, said descriptions of Omicron being a ‘natural vaccine’ were right.

The logic behind the argument is that as Omicron is highly transmissible but milder than other variants, it can give an immunity boost without causing as much serious illness, with some data suggesting a combination of infection than vaccination providing the best type of immunity in the long-run.

Future variants ‘may be even more mild’, Professor Jones told MailOnline, adding that the need for healthy adults to get top-up jabs could soon recede. Instead of doling out jabs every few months, he said annual boosters for the vulnerable ahead of the winter would be ‘more feasible’.  

Professor Lawrence Young, a virologist from Warwick University, insisted vaccines should protect against severe illness for much longer than they do against getting infected or becoming ill, suggesting that an annual booster for the elderly and vulnerable groups will be enough to thwart off Covid in the coming years.

Dr Simon Clarke, a microbiologist at the University of Reading, admitted he ‘can’t see’ ministers doling out Covid vaccines every three months for much longer. He said: ‘Although after two-and-a-half months immunity starts to wane, that doesn’t mean it drops below being extremely effective.’

But he told MailOnline that the only way to measure the long-term effectiveness of the boosters was to wait and see. ‘We can only get that long term data over the long term, there’s no crystal ball with this. We just don’t know what the optimum strategy is,’ he said. 

Other epidemiologists have said repeated and multiple outbreaks Covid each year might necessitate boosters every four to six months, which they branded a ‘daunting prospect’.   

But even though data shows vaccines are less effective against Omicron, they are nowhere near redundant.   

Real-world data shows efficacy levels of the booster vaccine at stopping people getting symptoms plummet to around 40 per cent after just 10 weeks. 

But two jabs still drastically cut the risk of hospitalisation and death, even against Omicron, as the body’s immune system still retains some ability to help fight off virus even after some waning immunity. A third dose will bolster that protection even further, experts insist.

It means a fourth dose may not be necessary yet for the entirety of the UK and could see ministers only advised to dish out extra doses to the elderly and immunocompromised in the coming months.

For this reason some experts have called for caution about dishing out another round of vaccines so quickly.   

One of the Government’s own advisers warned it would be impossible to ‘defeat’ Covid with vaccines if everyone needed a top-up every three months. It would see the NHS have to dish out the equivalent of up to 50million jabs every 90 days, or around 550,000 every day.

This would put the cost of an annual vaccination drive in the region of £4billion, based on one jab being priced at around £20 per dose — similar to Pfizer. 

But ministers may sign off on plans to dish out universal Covid jabs — which experts hope will offer better protection and hold up against variants that emerge in the future —  but they aren’t expected for another 18 months, England chief medical officer Professor Chris Whitty told MPs earlier this month.

Vaccine makers have been quietly working on as polyvalent Covid jabs but they are all in early development and way off clinical trials.

 Israel has already approved the use of fourth doses of Covid vaccines to vulnerable people, such as those with weakened immune systems, over fears that their immunity may already be fading .

Currently, the US has not indicated any plans regarding additional boosters, with health officials saying more data is needed on the protection improvement potentially offered by a fourth dose. 

Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases said last week that it was too ‘premature’ to be talking about a fourth dose.   

‘One of the things that we’re going to be following very carefully is what the durability of the protection is following the third dose of an mRNA vaccine,’ he said.

‘If the protection is much more durable than the two-dose, non-boosted group, then we may go a significant period of time without requiring a fourth dose.

‘So, I do think it’s premature, at least on the part of the US, to be talking about a fourth dose.’

UK experts have also urged caution over offering fourth jabs, saying more data is needed on the long term protection offered by the booster. 

The rollout of a second set of boosters is being examined by experts on the Joint Committee on Vaccination and Immunisation (JCVI). 

Professor Anthony Harnden, deputy chair of the JCVI, said: ‘We need to see more data. We are in different circumstances to Israel and we need to see more data on waning immunity and vaccine effectiveness against hospitalisation.’ 

Professor Jones said: ‘The vaccine response clearly wanes but it is not clear if the boosted response will wane in the same way or at the same rate.’ 

He also told MailOnline that he didn’t think offering a regular booster to keep immunity up was feasible or effective.

‘Boosting every 10 weeks or every time a new variant appears to be on the rise is not doable and in consequence I think we need some sort of grading system for new variants to ensure we act appropriately and practically,’ he said. 

Professor Jones said annual top-up jabs for the vulnerable ahead of the peak winter illness season, December to February, would make more sense. 

If all adults would need one depended on how Omicron continues to develop, Professor Jones said. 

‘If Omicron is an attenuated strain already on its way to endemicity then later versions may be even more mild and the need for vaccination for an otherwise fit adult might recede,’ he said.

‘You have to remember that making you very sick is no good to the virus at all, all it “wants” is to transmit, so virus evolution will tend towards a less severe strain which you will pass around as you will struggle on with work etc much as we do for common colds.’  

On Omicron generally Professor Jones said descriptions from others of the ultra-infectious variant being a ‘natural vaccine’ were right.

He said that while any Covid variant boosts immunity the fact Omicron was highly transmissible yet milder worked to help boost population immunity.

‘Whatever version you were infected with your immunity would be boosted,’ he told MailOnline. ‘That mild bit suits us because it means we can get immunity without, or with much less, risk.’

However, he warned against any ‘chickenpox’ style parties where people intentionally try to catch Omicron, saying we needed to protect people who could get severely ill from the virus. 

‘You have to be careful here not to stretch it to things such as chickenpox parties because there will always be a vulnerable minority and to encourage infection puts them at risk,’ he said. 

Hopes of Omicron ushering in the end of the pandemic stage of Covid were sparked by a South African study into Covid death rates in the nation’s Omicron wave. It showed fatalities were just a quarter of levels seen during other surges. 

Researchers examined records of 450 patients hospitalised in the City of Tshwane, in the ‘ground zero province of Gauteng, since the extremely-transmissible variant took off in the country. Their survival rates were compared to nearly 4,000 patients hospitalised earlier on in the pandemic.  

Just 4.5 per cent of patients hospitalised with Covid in the last month died from the virus. For comparison, the rate stood at around 21.3 per cent earlier in the pandemic  

Scientists from South Africa’s National Institute of Communicable Diseases (NICD) and the University of Pretoria, who carried out the research, said it shows ‘a decoupling of cases, hospitalisations and deaths compared to previous waves’. 

Omicron could be a ‘harbinger of the end’ of the darkest days of the pandemic and could usher in the virus’s endemic phase, the team wrote in the International Journal of Infectious Diseases. 

Commentators around the world have latched on the findings and claimed Omicron could act as natural vaccine making the virus endemic to the population.

One of these was a health official for the Indian state of Maharashtra, Dr Pradeep Awate who told the Press Trust of India, that although Omicron was spreading faster than Delta, there had been few hospitalisations.

‘If this happens, Omicron will act as a natural vaccination and may help in its (Covid’s) progression towards the endemic stage,’ he said.   

But Dr Clarke cautioned against the idea of labelling Omicron a ‘natural vaccine’. 

‘The immunity we’ve had from other variants doesn’t protect all that well against Omicron, so there is no reason to think it works in the other direction,’ he said. 

This is despite a new study from the Africa Health Research Institute showing blood taken from people infected with omicron recorded a 4.4-fold increase of antibodies when exposed to the the Delta version of the virus. 

In contrast other studies delving into the topic of cross-variant immunity showed antibodies made in response to Delta reacted poorly to Omicron. 

Dr Clarke added that just because Omicron was milder did not mean it, or other Covid variants, would remain so, adding: ‘The idea that viral evolution is a one-way street to the common cold is absolute bull****.’ 

On the idea of more boosters and how often, Dr Clarke emphasised the need for more data before we know time gap between more Covid jabs. 

He said there will be an ‘optimum’ gap between doses but ‘we just don’t know what it is yet’, adding that it ‘won’t be good’ if jabs are done too far apart or close together.  

Dr Clarke also advised against general predictions on how Covid boosters are going to be rolled out in 2022, highlighting how despite an Omicron jab being in development, it might fail, or need two doses similar to the initial Covid jab. 

However he did say that boosters being used to keep immunity against infection topped-up through increased antibodies may be the preferred strategy going forward by the Government not wanting to impose restrictions and minimise disruption.   

‘Population wide vaccination will drive down transmission, it won’t eliminate it, but it will drive it down across the population,’ he said. 

‘And if you have lots of people who have more than the sniffles and are ill enough not to go to work, there is massive damage to public services and an economic slowdown.’     

Professor Young also said while data had suggested a drop in booster effectiveness against Omicron infection, the outlook for longer term protection from against severe disease was still good.

‘Preliminary data suggests that vaccine effectiveness against symptomatic infection with Omicron drops by between 15-25 per cent after 10 weeks,’ he said.

‘Thus those older individuals who were boosted at the beginning of the booster campaign in mid-September may not be as well protected from symptomatic infection. 

‘However, all current data indicates that booster jabs will protect from severe disease and that this should last for at least several months.’

He said the broad hope is that this protection against severe disease will eventually mean an annual booster jab for the elderly and other vulnerable groups will be sufficient to protect them from a severe Omicron infection in the coming years. 

Professor Young also highlighted how immunity was a complex system, with different segments like antibodies rising in the short term when people get vaccinated. While other more difficult to measure parts like T-cells provide longer term protection.    

‘The good news is that recent studies have shown that both vaccination and natural infection induce a strong and sustained T-cell response to Omicron and other variants,’ he said.

‘This might be the key to longer term protection and the need for less frequent boosters.’

There have also been concerns about over-vaccinating people in the UK when so many in other parts of the world are unvaccinated.

Professor Adam Finn, a government vaccine adviser, previously told the BBC that over-vaccinating people, when other parts of the world had none, was ‘a bit insane, it’s not just inequitable, it’s stupid’.  

Professor Young also highlighted that it might be more important to help other countries boost their vaccine uptake rather than offer all Britons another booster, to stop new variants from forming. 

He highlighted Africa, where Omicron was first identified and almost certainly emerged, as one particular example.

‘Virus variants will continue to be generated as long as the virus is allowed to spread particularly in countries where vaccination rates are low,’ he said.  

‘This emphasises the need to control the pandemic at the global level as well as locally and that it is in all our interests to support the roll out of vaccines across the world.

‘In a situation where around 73 per cent of people in wealthy and middle-income countries have been vaccinated, this includes those who have had one, two or three doses, whereas only 12 per cent are vaccinated in Africa, we have to consider the value and luxury of additional booster doses if such vaccines are not widely available.’

Jeffrey Shaman, an infectious disease modeler and epidemiologist in New York has also highlighted the need to tackle the Covid pandemic on a global scale2.

He said: ‘We may find ourselves in a different kind of endemic equilibrium in which boosting is needed every four-six months and highly effective therapeutics are needed to limit severe disease. All this would need to be available globally and equitably. This is a daunting prospect. And psychologically challenging.’