This is a curious story, even though it’s common: A household is hit with Covid. But one member of the family never gets a positive test or has a sniffle. 

Meanwhile, there are people who have received Covid but were double-jabbed or boosted and still get the virus.

As infections continue to soar in the new Omicron wave – an astonishing one in 25 people in England have Covid, according to Office for National Statistics data – cases of people who managed to stay free of the infection become ever more remarkable. Or is this luck? Is it some kind of superpower

Researchers may soon have an answer. Evidence is mounting that Covid-resistant individuals exist.

These people are believed to be immune to the Covidvirus, although this is not clear. 

It is currently the topic of extensive research all over the globe. 

Nasim Forooghi (pictured), 46, a cardiac research nurse at St Bartholomew's Hospital in Central London, has been potentially exposed to hundreds of people infected with Covid since the start of the pandemic, but has had a succession of antibody tests which found no trace of the virus ever being in her system

Nasim Forooghi (pictured), 46-year-old cardiac research nurse at St Bartholomew’s Hospital, Central London has been possibly exposed to Covid infected people since the outbreak. But, she had several antibody tests and found that there was no sign of Covid in her system.

There is mounting evidence that some people are naturally Covid-resistant

Evidence is mounting that certain people may be Covid-resistant.

And at University College London (UCL), scientists are studying blood samples from hundreds of healthcare staff who – seemingly against all odds – avoided catching the virus (file image)

And at University College London (UCL), scientists are studying blood samples from hundreds of healthcare staff who – seemingly against all odds – avoided catching the virus (file image)

The flu jab can boost immunity against Covid

If you aren’t fortunate enough to be naturally Covid-proof, is there anything else you can do to bolster the immune system and gain better protection against the virus?

Of course there are the basic principles: avoiding smoking, maintaining a healthy weight, and getting a vaccine booster are all tried-and-true methods.

Vitamin D supplements have been touted, too, as the compound is known to be involved in the body’s immune response to respiratory viruses. But while this could theoretically work, at the start of December the National Institute for Health and Care Excellence concluded there was ‘little evidence for using Vitamin D supplements to prevent or treat Covid-19’.

A fascinating suggestion is that obtaining a flu vaccination may help protect against the coronavirus.

As reported by The Mail on Sunday last month, flu has all but disappeared for the second year running – and scientists now suggest that Covid vaccination, or infection, might ‘rev’ the immune system and guard against flu infection as a welcome secondary benefit. However, the opposite is true: a flu jab can also increase immunity to Covid.

The immune system responds to any infection by activating a vaccine or by infecting the body with virus.

The flu-specific immune cells (or antibodies) that are derived from having been infected with the virus or receiving a vaccine are more effective at quickly alerting other cells about an intruder.

A second line of defence are fighter cells called T cells. These cells are released in response to infection or a jab. They are less specific and can be used for general defense.

‘Antibodies are like snipers and can spot a particular illness and keep it out, while T cells are more like machine guns and offer more general protection against viruses,’ says Dr David Strain, senior clinical lecturer at the University of Exeter Medical School. ‘If someone has a good T cell response, their chances of infection with something else are a lot lower.’

Striking evidence from the US shows that people who had had a flu vaccine were 24 per cent less likely to catch Covid-19 – regardless of whether they’d had the Covid vaccine. People who contracted Covid had a lower likelihood of needing ventilation or hospitalization.

According to the American Journal Of Infection Control scientists, this could result in a stronger T-cell response after the flu jab.

And it’s not just antibodies and T cells: exposure to a virus or its vaccine can also ramp up another type of specialised cell – macrophages, which are particularly effective for fighting respiratory viruses.

‘Macrophages destroy bacteria, so clear debris and dead viral cells in the lungs,’ explains Professor James Stewart, Chairman of Molecular Virology at the University of Liverpool.

‘This is helpful with both flu and Covid-19. So exposure to both viruses hypes up the immune system, meaning that people will get some protection against both.’

Scientists believe that the lucky people could be able to reveal clues that can help create a new variant of a vaccine that would keep Covid away forever.

Scientists in Brazil and America are investigating genetic mutations that may make it more difficult for certain individuals to contract the virus. 

And at University College London (UCL), scientists are studying blood samples from hundreds of healthcare staff who – seemingly against all odds – avoided catching the virus.

One such frontline worker is Lisa Stockwell, a 34-year-old nurse from Somerset who worked in A&E and, for most of 2020, in a ‘hot’ admissions unit where Covid-infected patients were first assessed.

She signed up with a nursing agency towards the end last year, where she was assigned daily shifts on Covid wards. 

Her colleagues have been referred to as ‘dropping like flies’ by their coworkers at different points during the pandemic.

However, she said that “I wasn’t sick” and her antibody test which was taken at the conclusion of 2020 before my vaccination was completed, came back negative.

I expected to be positive at some point but this never happened. Although I am not sure if I have an immune system that is very strong, I feel grateful to not have been sick.

Lisa and her family were among the first to succumb to the disease during the pandemic. 

She says that she was “sick for over two weeks and had a terrible fever which left me delirious.” 

“He was very sick, but refused hospitalization. 

“Despite sharing a bed, I never caught it. 

“And my mother was completely shocked, even though she is now 63 years old and has rarely been seriously ill.” 

“I even drove a friend of mine to work each day for two weeks. But, days later, I was laid low by Covid.

Lisa had 2 jabs, and Lisa needs a booster. 

And like millions of us, she uses a lateral flow test before socialising – but never because she fears she has Covid symptoms. 

She said, “I used to work every day at Covid wards in PPE of poor quality and was scared that I might catch the disease.” 

“But I didn’t do it, and now I think I might never.” 

Nasim Forooghi (46), a central London cardiac researcher nurse, had a similar story.

The mother-of-two, whose husband is an NHS doctor, has been heavily involved in research tracking Covid among frontline staff – a role that has potentially exposed her to hundreds of infected people since the pandemic began in early 2020.

Lisa also had several antibody tests that found no evidence of the virus in her body.

Nasim states, “Clearly I was wearing protective clothing. But, even then, I was exposed a lot to infected individuals.” 

“I don’t know what it could have been, but I think my strong immune system was responsible. Or maybe luck. 

“I went to blood testing every week and they did not find anything, even though I had been exposed to the substance regularly.”

Elle adds that she dealt daily for several weeks with nurses and doctors who worked on the front lines and were face to face with patients at Covid wards. 

‘At home, we’ve been lucky, too – neither my husband nor children have caught the virus.’

When the UCL researchers examined the blood of seemingly Covid-proof healthcare workers that had been taken before the vaccine rollout, it confirmed they had no Covid antibodies – meaning it was unlikely they had ever been infected.  

But, the researchers discovered that T cells were also present in immune system cells. These cells are very similar to immune systems found in those who had recovered from Covid.

To fight invaders, T cells can be created by your immune system just like antibodies. However, while antibodies prevent viruses from getting into the body’s cells, T cells destroy and attack them.

Now it is known that Covid antibodies may begin to decrease in just a few months after an infection or after vaccination. 

Experts suggest that T cells are retained in the system longer, and the virus will be eliminated before the chance for it to infect other cells.

But they are still there. 

The theory goes that this protection is due to the fact that it was provided by past regular exposure. 

This could have been through their jobs dealing with sick patients or facing other, less destructive types of coronavirus – the type of disease that includes Covid, of which four strains cause common colds.

COVID Q&A: Can we cut isolation, do boosters last, and what hope for 2022?  

Q: Can we reduce isolation to just five days like the US?

A: American officials reduced the time for isolation of people suffering from asymptomatic coronavirus by half last week to just five days. 

Amid a surge in cases – there are more than half a million new cases in America every day at present – it is hoped this will ease staff shortages, with officials arguing that a person is most infectious two days before and three days after symptoms develop. 

The isolation process did not require that you test negative for any reason.

The UK authorities have not followed suit. Instead, they require that people isolate for 7 days and then conduct two negative lateral flow test on the sixth and seventh days. Professor Lawrence Young of University of Warwick called this “the right approach”.

According to him, there is not enough evidence that a person can be infected after just five days. This includes if the test results are negative. It is extremely risky.

Covid doesn’t have an “off switch” and infectiousness slowly decreases from peak levels around symptoms to zero. Some individuals might be still infected after just five days.

US officials suggest that you wear a mask for at least five days after isolation.

Senior clinical lecturer in the University of Exeter Medical School says that “Masks reduce spread by 88% to 89%.” A person who tests positive for the virus five days before is at risk of getting sick by a 80% reduction in spread, even though they have tested negative, still puts people at high risk.

Anecdotally, patients have reported night sweats and low appetite with Omicron –symptoms that are not officially listed by US officials.

Andrew Preston is a University of Bath biologist. He says that balancing the harms and risks has always been the core of all policies. This is still a difficult task.

Q: According to what I have read, the booster can last only 10 weeks. Do I need to be concerned if the booster is still in use after I’ve used it?

A: As of Friday, every adult in the UK has been offered a booster – the programme began in September. 

Research shows that Omicron protection begins to fade within three months. A booster of Pfizer’s Moderna or AstraZeneca vaccine was effective in preventing symptoms for those who had received at least two doses. It proved to be between 60% and 94% effective. This happened within two weeks of receiving the AstraZeneca vaccination.

Within ten weeks the Pfizer booster proved to be effective at 35% and Moderna booster at 45%, respectively.

The vaccine efficacy of those who had received three doses from Pfizer was 70% approximately a week following the booster, but fell to 46% after 10 weeks.

In addition, the effectiveness of those who were given a Pfizer vaccination in a series of two doses and then received Moderna boosters after each subsequent dose seemed to be at 75%. This was up for nine weeks.

But Dr Clive Dix (ex-chairman of the UK Vaccine Taskforce) said that this was not necessarily cause to alarm. 

“To date, vaccines have all protected against serious disease. This includes hospitalisation and death. It is reasonable to expect that the effectiveness of these vaccines against severe diseases will not be lost.

Q: What will happen to this pandemic by 2022?

A: One of the best things about Omicron, which is believed to cause nearly 200 000 new cases per day across the UK, is that it is more severe than Delta. This means there is up to 70% less chance of needing hospitalisation. 

Viral diseases can become milder over time. Experts say that widespread immunity against vaccinations may be responsible for the reduction in hospitalisations.

Dr Strain explained that they only have unvaccinated young patients in their ICU.

Eight Nightingale surge hubs are currently being built across England in order to meet expected demand.

Some 11,452 patients with coronavirus were on wards in England on Thursday – up by 61 per cent in a week.

Chris Hopson from NHS Providers represented hospital trust leaders and said: “Though the numbers keep going up, it is important to note that there are not many older seriously ill people. It gives us a sense of security.”

Dr Strain stated that he hoped to be able to read the Greek alphabet by the time he was older. [with naming new variants]We will soon see an illness that is not as severe as the common cold. I’m not convinced we are there yet.  

Of course there is the possibility that the healthcare workers picked up Covid but suffered no symptoms – at the start of the pandemic, up to half of cases were thought to be asymptomatic. 

However, the UCL team performed further testing on hundreds more samples of blood collected long before 2011 and found that around one in twenty had antibodies that could eliminate Covid.

The highest levels were found in samples taken from children. Scientists speculate that this may be due to the fact that children are often exposed to cold-causing coronaviruses by being in close contact with many other kids during school and nursery.

It is important to ask: How will scientists use the latest research to develop a vaccine that can be used against variants? 

This could lie in how the immune system functions.

Many Covid vaccines replicate the spike protein on the outside of virus cells. This is what allows the virus cells to infect healthy cells and establish camp inside the body. 

This triggers your immune system to produce antibodies and T cells to combat the Covid virus should the latter enter your body.

However, Covid vaccines only work if your immune system recognizes the spike protein from a Covidvirus as soon as it infects you. 

Like Omicron, if the spike protein is mutated to the extent that it’s almost inaccessible to the immune system (or becomes nearly unrecognisable), both T cells and antibodies will be less effective.

This is the point where UCL’s findings are most relevant. The most plausible explanation for the Covid-proof immunity system may be that it recognizes proteins inside the virus, rather than its surface, and is then capable of detecting and eliminating any mutant relatives. 

There are few differences between the coronaviruses. Professor Andrew Easton from Warwick University says that internal proteins are not susceptible to mutations at the rate of external ones.

These stable proteins have been sought out by vaccine-makers. Emergex, a biotechnology company based in Oxfordshire is currently testing one.

It has developed a skin patch – rather than a jab – which sticks on the upper arm. It uses tiny, painless micro-needles to puncture the skin. Fragments of various viral proteins can seep into the bloodstream. 

The initial trials, which involved 26 volunteers, will begin in Switzerland. Results are expected to be available by June.

“These Covid vaccines of second generation will focus on parts of the virus less susceptible to changing than spike protein,” says Lawrence Young, a Warwick University virologist. 

“They target virus parts that are common to different virus families, thus they can be active not just against Covid-19, but also all coronaviruses.

‘Proteins other than the spike protein are much less flexible and less likely to change – they will be much less of a moving target.’

With more than half of the population getting a crucial third dose that provides protection at minimum 70% against Omicron-related symptoms, the booster program is already a great success.

Scientists warn that more vaccine-resistant strains are inevitable.

Prof Young says that the reason the public is so excited about booster jabs at the moment is because of Omicron’s fear and panic. 

“But we have to be careful. If we ask people to take extra vaccines, it is a problem. We know from other vaccination programs that compliance decreases.

One example is flu jabs. Only two-thirds (or less) of UK citizens who were eligible for flu vaccinations, which are given once per year, had ever taken the time to get it before the Covid pandemic. The pandemic triggered a huge surge – to 91 per cent.

Another plausible hypothesis is that natural Covid resistance – and a potential preventative treatment – lies in the genes. 

Researchers at the University of Sao Paulo, Brazil have discovered that 100 couples were infected with the Covid-specific antibody. One of the infected was symptomatic and the other had never been tested positive. Blood tests also confirmed that they did not have the antibodies. This makes it unlikely that they ever contracted the virus. They will also have their DNA tested to determine whether there is any significant difference.

Mayana Zatz (the lead researcher) and genetics expert said that it was relatively easy to find volunteers for the Covid study. “We got about 1000 emails from people stating that they were in the same situation.”

It has also been observed that genetic resistance can be found with other viruses. Doctors discovered that Stephen Crohn (an American man) had not been infected by HIV, even though he was exposed to many HIV-positive people.  

The big question is, how will the new research help scientists develop a variant-proof vaccine? (Pictured: A member of the public receives a dose of a Covid-19 vaccine inside a vaccination centre set up at Grim's Dyke Golf Club in north west London on Christmas Eve, 2021)

 The big question is, how will the new research help scientists develop a variant-proof vaccine? (Pictured: A member of the public receives a dose of a Covid-19 vaccine inside a vaccination centre set up at Grim’s Dyke Golf Club in north west London on Christmas Eve, 2021)

He was found to have a mutation in HIV that hinders its ability to penetrate the cells of his body.

Jean-Laurent Casanova is an immunologist at Rockefeller University in New York. He has been researching how genes affect the severity and duration of Covid disease that an individual with Covid suffers. Now, he’s focusing on Covid resistance. According to him, if you knew that you were resistant, then you would be more relaxed. King Kong would make you feel great, wouldn’t he?

Dr Casanova proposes that “gene blocking” treatments may one day be made available for people who have not developed resistance to the virus. They would also, unlike standard vaccines, be effective against new variants and eliminate the need for boosters.

Some experts are optimistic, stating that scientists may have already found the right jab. Professor Julian Tang of Leicester University is a virus researcher. He says that he believes the virus will be enough to end this pandemic. It seems like it’s evolving into something more benign.

‘The history of many viruses – including the Spanish flu of 1918 – is that they become more harmless in time. Omicron appears to be significantly less severe than other variants. However, it’s surprising it happened so quickly.

“I had expected the transition from dangerous and deadly virus to be a gradual process that would last five to ten more years. But it appears it may happen faster than I thought.”