Immunity

Why Are Sweden and India Not Seeing a Covid Surge?

Why are some countries surging this autumn but others aren’t, at least not yet? Much of Europe is now seeing sharp rises in reported infections. In some it appears to be a delayed Delta surge, but in others like France, Netherlands, Norway and Finland it comes after an earlier summer Delta ripple that looked like it had gone away. Yet India, which had (quite literally) the mother of Delta surges, has not seen any new rise despite only 29% of its population being double-vaccinated, and despite the festivals of Diwali and Durga Puja, widely warned about as a transmission risk, taking place in the autumn.

Sweden, meanwhile, has somehow so far managed to avoid Delta surges altogether, after being hit relatively hard in spring 2020 and winter 2020-21. The country famously imposed only light restrictions (no stay-at-home orders, school or business closures or mask mandates at any point). Similarly, few restrictions were imposed in India in 2021, and there is also doubt about how far Indian citizens have followed any restrictions that were brought in; in any case, high population antibody rates were subsequently reported. Are India and Sweden benefitting from a more robust immunity owing to greater exposure prior to this autumn? What happens this winter will help to clarify this question.

The U.K. meanwhile is experiencing a strangely drawn-out Delta epidemic. Beginning in June, it has now been simmering away at around about the same level for five months, neither exploding as the models predicted, nor dropping off again back to low levels, as earlier waves have done.

Decline in Flu Immunity Due to Clampdown on Socialising Has Led to ‘Worst Colds Ever’

Some Brits say they are suffering from their “worst cold ever” as scientists warn that the decline in flu immunity during continued lockdowns could lead to a difficult winter. The Independent has the story.

For Rebecca London, 24, from Bournemouth, a usual cold would mean “a runny nose, sneezing, a bit of a sore throat and feeling a bit rundown”.

“Nothing like this,” she told the BBC, saying she could barely sleep during her illness, which numerous lateral flow tests confirmed was not Covid.

Others have spoken of being “floored” by their colds, some of which lasted for more than a month.

Dr. Philippa Kaye, a GP in London, told the broadcaster: “We’ve actually been seeing a rise in the number of coughs and colds and viral infections.

“We are mixing in a way that we haven’t been mixing over the past 18 months.

“During those first lockdowns, we saw numbers of other [non-Covid] infections fall. We think that that was primarily due to the restrictions on meeting up.”

In more positive news, the World Health Organisation’s latest influenza update suggested that global cases were “at lower levels” than predicted for this time of year, despite fears of mass outbreaks.

However, with winter approaching, the situation could get worse, as Professor Anthony Harnden, the Deputy Chair of the Joint Committee on Vaccination and Immunisation, has warned. He said that low flu immunity “could be potentially a bigger problem this winter than Covid”.

Worth reading in full.

We Should Have Trusted Our Immune Systems

There follows a guest post by retired dentist and Daily Sceptic contributor Dr. Mark Shaw, who says that just as dentists are taught to intervene as little as possible and trust the human body, public health experts should heed the same lesson.

As well as dentistry, sport has played a big, happy part of my life. Athletics, cross country and squash mainly but also many other competitive sports. So I was relieved to find that, following a long spell on the NHS waiting list, I wouldn’t need a hip replacement after all. I’d used the waiting time to do as much research on hip physio as possible and found that my mobility was improving steadily and significantly. My experience and knowledge of sports injuries through intense training and competing for my country had definitely helped.

When I sat down with the consultant for the assessment of my hip I described the progress made and how keen I was to avoid, or at least put off, an operation. The consultant orthopaedic surgeon seemed happy with my attitude and said that nothing would improve on my original hip and that, no matter how bad the hip looked on the X-ray, as long as I could function and manage the pain, I should avoid surgical treatment and continue with my physio and general health measures. Happy days!

This experience reminded me of my own profession (including its history) and the training involved and how medical science has responded to Covid.

In the early years of training we were taught about the ‘old’ treatments and how advances in technology had changed the way we removed decay and designed restorative work (fillings, crowns and bridges etc.). After qualifying and through the years this theme continued. Restorative work involves working out how little, if any, healthy tooth tissue you can get away with removing. All our technology and materials still can’t beat the real thing.

Prevention of the causes of gum disease and tooth decay through education is therefore the most important aspect of dentistry in my opinion. Appropriately frequent monitoring (check-ups) – and treatment as a last resort.

New Zealand Hospitals Flooded with Children Due to Immune Systems Weakened by Lockdown, Doctors Say

New Zealand and Australia are currently seeing a large number of children in hospital with respiratory illness, which doctors are blaming on the lockdowns for keeping them away from bugs. The Guardian has the story.

Wellington has 46 children currently hospitalised for respiratory illnesses including respiratory syncytial virus, or RSV. A number are infants, and many are on oxygen. Other hospitals are also experiencing a rise in cases that are straining their resources – with some delaying surgeries or converting playrooms into clinical space.

RSV is a common respiratory illness. In adults, it generally only produces very mild symptoms – but it can make young children extremely ill, or even be fatal. The size and seriousness of New Zealand’s outbreak is likely being fed by what some paediatric doctors have called an “immunity debt” – where people don’t develop immunity to other viruses suppressed by Covid lockdowns, causing cases to explode down the line. …

The “immunity debt” phenomenon occurs because measures like lockdowns, hand-washing, social distancing and masks are not only effective at controlling COVID-19. They also suppress the spread of other illnesses that transmit in a similar way, including the flu, common cold, and lesser-known respiratory illnesses like RSA. In New Zealand, lockdowns last winter led to a 99.9% reduction in flu cases and a 98% reduction in RSV  and near-eliminated the spike of excess deaths New Zealand usually experiences during winter.

Keeping children away from bugs means they don’t develop immunity and results in an “immunity debt” that must be paid sooner or later, a group of doctors explains.

Covid Vaccination Open to All over-18s in England

All English adults are now able to book a Covid vaccination as the number of over-18s who have been vaccinated nears 45 million (over 80%) – yet still we wait. Reuters has the story.

Prime Minister Boris Johnson on Monday pushed back the full re-opening of England from lockdown until July 19th because of a rise in cases, but also accelerated his vaccination plans, pledging to give every adult a first dose by the same date. 

“Offering all adults a jab less than 200 days after the programme launched is one of our country’s greatest collective achievements, saving over 14,000 lives so far,” he said, referring to Public Health England estimates of the impact of the vaccine roll-out.

Britain has given a first dose of a Covid vaccine to more than 42 million people, almost 80% of adults, while well over a half have received both shots.

Health authorities in England, Wales, Scotland and Northern Ireland each run their own vaccination campaigns. Wales and Northern Ireland have already made vaccines available to any adult, while Scotland is offering them to anyone over 30.

In Monday’s briefing, the Prime Minister said that current vaccination levels were not enough to justify unlocking the country and that two-thirds of the adult population must be fully vaccinated (a milestone that is expected to be reached by July 19th) if there is to be an effective “wall of immunity”. Even then, he warned that “a proportion of the elderly and vulnerable may still succumb [to the virus] even if they have had two jabs”.

The Reuters report is worth reading in full.

Vaccination Doesn’t Add Any Protection to that Gained from Previous Infection – Study

A new study (not yet peer-reviewed) of over 50,000 employees of the healthcare system in Cleveland, Ohio, has found that previous infection provides very robust protection against re-infection and, importantly, that there is no gain to being vaccinated as well.

U.S. Senator Rand Paul tweeted the study’s conclusion: that it means vaccines should be prioritised for the not-previously-infected at home and abroad, not wasted on the already immune.

The confirmation of the protection provided by natural infection is very welcome, as is the finding that vaccinating the previously infected is superfluous. Given the significantly higher risk of adverse events for those previously infected (up to three times higher according to the ZOE Lancet study) and the world shortage of vaccines, there would seem to be a moral imperative to cease vaccinating the previously infected.

The study’s finding is particularly robust because of the large sample size and because there were zero instances of re-infection among the previously infected (both vaccinated and unvaccinated). This was despite the study period beginning at the peak of Ohio’s winter wave, so the unvaccinated had plenty of exposure to the virus. Other studies have found the relative risk reduction offered by previous infection to be 80% against all re-infection and 90% against symptomatic re-infection, so the results in this study were even higher than usually observed.

However, the study’s findings for vaccine effectiveness in the not-previously-infected are much less reliable.

You Can Catch Covid Twice – But it’s Very Rare and Very Mild

Can you catch Covid twice? The challenge trials at Oxford University have now turned their attention to this question, deliberately exposing people who have had the disease before to the virus again to see how their immune systems respond.

Other studies have already looked into this question, though without the controversial deliberate exposure aspect. The most recent, published in the Lancet last week, tested around 3,000 U.S. Marine recruits aged 18-20 for Covid antibodies and then followed them over six weeks while they completed basic training together to see how many became infected. The living in close quarters would likely have ensured that all were exposed to the virus.

The study found that around 10% of seropositive (with-antibodies) participants (19 out of 189) tested PCR positive for the virus versus around 50% of seronegative participants (1,079 out of 2,247). This means that having antibodies from a previous infection gives about 80% protection from testing positive for the virus again. This finding closely matches that of a large Danish study published last month, that found those who had tested positive for the virus in the spring were about 80% less likely to test positive again in the autumn. And also a UK study of NHS workers from January that found being PCR positive for the virus at one point made workers around 80% less likely to test positive again at a later date.

The new study was being used last week to promote the idea of vaccinating young people who had previously been infected, on the grounds that protection via infection was not enough. Thus Sky News reported: “Young people who have already tested positive for coronavirus are not fully protected against reinfection.”

The study itself supported this use, stating its results suggest “COVID-19 vaccination might be necessary for control of the pandemic in previously infected young adults”. Professor Stuart Sealfon of Icahn School of Medicine at Mount Sinai, New York, and senior author of the study, said:

As vaccine rollouts continue to gain momentum it is important to remember that, despite a prior COVID-19 infection, young people can catch the virus again and may still transmit it to others. Immunity is not guaranteed by past infection, and vaccinations that provide additional protection are still needed for those who have had COVID-19.

What such claims appear not to allow for is that questions are being asked about how the balance of risks stacks up for young people to be vaccinated even when they have not had Covid, let alone when they have and have 80% protection already. To this balance must be added that severe side-effects are considerably more common in those who have previously had Covid.

The 80% protection figure is also not the full story on immunity following infection. Noteworthy is that symptomatic infection was much less common among those who had antibodies. In fact, only three out of 19 (16%) seropositive PCR positives were symptomatic, versus 347 out of 1,079 (32%) seronegative PCR positives. The large proportion of PCR positive infections that are asymptomatic even among those without antibodies (68%) may be an indication of the high degree of pre-existing immunity among the young.

The infections among those with antibodies were also much less likely to be infectious, with average Ct of 27-28 versus around 24 for the seronegative infections (Ct or cycle threshold corresponds inversely to viral load, which corresponds to infectiousness). This translates to a viral load about ten times lower, which is considerably less infectious.

U.K. Trial Launched to Deliberately Infect People with Covid after They’ve Already Had It

Researchers at the University of Oxford have launched a trial that will deliberately expose people who have already had Covid to the coronavirus again to study the level of immune protection needed to prevent reinfection (assuming reinfection is possible). It is hoped that the study will aid the development of treatments and vaccines. The Guardian has the story.

The first human challenge trials for Covid began this year, with the study – a partnership led by researchers at Imperial College London among others – initially looking at the smallest amount of virus needed to cause infection among people who have not had Covid before.

Now researchers at the University of Oxford have announced that they have gained research ethics approval for a new human challenge trial involving people who have previously had coronavirus. Recruitment is expected to start in the next couple of weeks.

“The point of this study is to determine what kind of immune response prevents reinfection,” said Helen McShane, a Professor of Vaccinology at the University of Oxford, and Chief Investigator on the study.

McShane said the team would measure the levels of various components of participants’ immune response – including T-cells and antibodies – and then track whether participants became reinfected when exposed to the virus.

Participants must be healthy, at low risk from Covid, aged between 18 and 30, and must have been infected with the coronavirus at least three months before joining the trial. As well as having previously had a positive Covid PCR test, they must also have antibodies to Covid. Given the timing criteria, McShane said it was likely most participants would have previously been infected with the original strain of the virus.

The first phase of the trial will initially involve 24 participants split into dose groups of three to eight people who will receive, via the nose, the original strain of coronavirus. The idea is to start with a very low dose and, if necessary, increase the dose – up to a point – between groups…

The second phase of the study – expected to start in the summer – will involve a new group of participants and will study closely their immune response before and after exposure to the virus, as well as the level of virus and symptoms in those who become reinfected.

The vaccines which produce the required level of immunity – as determined by this study – could have their licensing fast-tracked without trials of thousands of people, according to Professor McShane.

If we can determine the level of immune response above which an individual cannot be infected, then that will help us determine whether new vaccines will be effective without necessarily having to test them in phase three efficacy trials.

Worth reading in full.

New Study: Exposure to COVID-19 Confers Immunity Even When Not Infected

The mainstream preoccupation with antibodies as a signal of protection from COVID-19, coupled with worries about their declining levels, often fails to acknowledge the crucial role played by T-cells in conferring longer lasting immunity.

A new study in Nature shows that not only do people infected with SARS-CoV-2 develop lasting T-cell immunity, but so too do their close contacts who never experience a detectable infection and have no detectable antibodies.

The authors write:

Close contacts, who are SARS-CoV-2-exposed, are often both NAT [PCR] negative and antibody negative, indicating that SARS-CoV-2 failed to establish a successful infection within these individuals, presumably due to their exposure to limited numbers of viral particles or a short time of exposure. However, our analysis of the samples from 69 of these close contacts showed the presence of SARS-CoV-2 specific memory T-cell immunity.

For those infected, the study found the level of T-cell immunity was similar regardless of whether the infection was severe, moderate or asymptomatic. It also found T-cell levels stabilised and did not diminish over the course of three months, implying lasting protection.

For close contacts who were not infected, there were some differences in the quality of their T-cell immunity compared to those infected. The authors write:

The size and quality of the memory T-cell pool of COVID-19 patients are larger and better than those of close contacts. … The results show that 57.97% and 14.49% of close contacts contained virus-specific memory CD4+ and CD8+ T-cells, respectively.

Disappointingly, the study found that in those never exposed to SARS-CoV-2 (because the samples came from before September 2019) there was no evidence of T-cell cross-immunity from other coronaviruses.

In order to investigate whether the observed expanded T-cells may have originated from pre-existing cross-reactive T-cells specific for common cold coronaviruses from previous infections, we tested blood samples of 63 healthy donors collected before September of 2019. Following a 10-day in vitro peptide expansion only 3.17% of the healthy donors contained detectable levels of virus-specific memory CD4+ and CD8+ T-cells, respectively, suggesting that cross-reactive T-cells derived from exposure to other human coronaviruses do exist but are at a significantly lower frequency than those observed in close contacts.

They acknowledged that this was contrary to other recent studies and suggested the issue needed further study.

In agreement with recent reports,17,25 our data also demonstrated the presence of cross-reactive memory CD4+ and CD8+ T-cells, which target various surface proteins of SARS-CoV-2, in unexposed healthy donors. However, the failure of these cross-reactive memory CD4+ and CD8+ to expand in vitro suggests they have limited potential to function as part of a protective immune response against SARS-CoV-2. It is noteworthy that the SARS-CoV-2-reactive T-cells detected in the unexposed healthy donors in our study were lower than those detected by Grifoni et al.17 and Braun et al.26, but were consistent with those reported by Peng et al.27 and Zhou et al.28 Assumably, due to the use of different methodologies in assessing SARS-CoV-2-specific T-cell responses, it is difficult to directly reconcile the cell-number data between different studies. Thus, a thorough investigation is needed to determine whether the cross-reactive T memory can provide any protective immunity and exert an influence on the outcomes of COVID-19 disease.

The fact that exposure to SARS-CoV-2 can result in the development of more robust immunity (perhaps because of an immune system part-primed from earlier viral infections), rather than infection, is a salutary reminder of how the circulation of viruses helps us to develop and maintain healthy immune systems capable of fighting off a variety of diseases. Trying to avoid infection by staying away from people, insofar as that is possible, can be counterproductive as it can weaken our immune system by leaving us unexposed to a whole variety of pathogens.

It’s also a reminder that antibody testing is a very limited way of determining who has been exposed to and developed immunity to COVID-19. If millions of people exposed to the virus are developing immunity without ever being infected or developing antibodies, what does that mean for reaching herd immunity? It must be closer than we think.

Are Masks Stopping Us From Building Up Immunity? A Paramedic Writes…

A Lockdown Sceptics reader who is a paramedic of four years’ experience has written to tell us about how through her job she encounters hundreds of sick people and hardly ever gets ill, despite never wearing a face mask before the pandemic.

When I began in the ambulance service several years ago and would attend patients with a wide variety of contagious illnesses, I found myself experiencing near-constant cold-like symptoms. These did not necessarily develop into anything worth taking more than a couple of paracetamol for, but it was enough to be noticeably waking up with a sore throat or stuffed nose every morning. On speaking to many of my colleagues, they all recall similar experiences.

As time went on and I continued exposing myself to a plethora of pathogens, I began to find that illness became an unfamiliar state. I’d attend patients and be so convinced I’d catch whatever bug they had that I’d spend the following job with pseudo-nausea. And yet despite being in close proximity and often in the confined space that is the back of an ambulance, with no mask or PPE and with coughs, sneezes, diarrhoea and vomiting, surprisingly I would very rarely contract anything. In five years I can recall a handful of colds, two bouts of vomiting for a few hours, and one case of the flu which still wasn’t as severe as many people experience.

Whilst the use of masks may have little demonstrated impact on the overall spread of Covid, I have often wondered to what extent PPE may be “protecting” us from other contagious particles. If so, what harm is this doing in the long term by not allowing our immune system to continually develop its innate defences? It’s illogical to expect to gain muscular strength being sedentary, yet it seems an alien concept to many to apply the same principle to our immunity.

Should a time ever come when we are no longer advised to wear masks and people no longer scrub their shopping to within an inch of its life, will we potentially see an influx of people becoming more frequently or severely ill from what would have ordinarily been relatively harmless germs?

I’ve certainly noticed a recurrence of prolonged sniffles since I stopped being so ‘contaminated’ all the time.