Oxford University

One in Three who Isolated Were Never Contagious, Study on PCR Threshold Data Suggests

Up to a third of people who tested positive for Covid by PCR test were not contagious and did not need to self-isolate, a new study led by Oxford scientists suggests. The Telegraph has the story.

Up to a third of people who tested positive for coronavirus by Polymerase Chain Reaction (PCR) tests were not contagious and did not need to self-isolate, a new study suggests.

Research led by academics from the University of Oxford found that many laboratories are setting the positivity bar very low, meaning they are picking up people who are “a danger to no one”.

PCR tests work by cycling swab samples through different temperatures to trigger replication, which releases a chemical showing that the virus is present. 

The fewer cycles that are needed to detect the chemical, the greater the viral load and the more likely someone is infected. 

There is no definitive cycle threshold level for positivity. However, a review by the University of Oxford found that 30 was a good cut-off, because the virus was unlikely to replicate after that – particularly in asymptomatic people. Other groups have suggested around 32 to 33.

However, Freedom of Information requests made by members of the public and compiled by the University of Oxford show that NHS trusts are using vastly different cut-off thresholds, with little regulation from the Government. Some are as low as 25, while others are as high as 45.

The figures also show that between 23% and 37% of people who were told they were positive had a cycle threshold value above 30. For one in 20, it was higher than 40. 

Dr Tom Jefferson, co-author and an epidemiologist at the Centre for Evidence-Based Medicine at the University of Oxford, said: “We found that about one-third of people who isolated probably didn’t need to. 

“PCR positivity means that you can tell people to isolate and ruin their lives basically, even though in a large proportion of these cases, they are not infectious.

“It’s absolute chaos. The whole regulation of these tests seems to be shambolic.” …

Prof Carl Heneghan, director of the Centre for Evidence-Based Medicine at the University of Oxford, said: “It’s deeply worrying. When you have more virus circulating in the community, the potential for contamination is greater. Studies have shown that people can be easily contaminated with a viral fragment. 

“The problem is the panic of the pandemic meant that we developed policies at a speed we’ve never seen before and we haven’t looked at them to find out which are evidence-based. 

“Accurately knowing who is infectious is incredibly important for people going about their daily lives, the economy, our social lives and our wellbeing. The impact on the economy is now coming home, and it is clear that we cannot afford to keep isolating people.

“It’s also clear that members of the public were worried about this and submitting sensible Freedom of Information requests, but were met with contradictory responses attempting to explain a system which is shambolic in terms of governance and regulation.”

The study will be published on the website of Collateral Global, a charity committed to researching the impact of Covid measures.

Worth reading in full, and find the study here.

Why Does Natural Immunity Not Exist For the QCovid Risk Calculator?

There follows a guest post by a Daily Sceptic reader, who wishes to remain anonymous, who has some questions about the changing risk estimates being produced by the QCovid risk calculator and why important factors like previous infection are not taken into account.

The QCovid risk calculator was developed by University of Oxford, commissioned in 2020 by the Chief Medical Officer for England on behalf of the U.K. Government, and describes itself as a “clinical decision tool intended to support conversations between clinically trained professionals and patients about COVID-19 risk”. There is a clinician tool and a patient tool; the clinician tool differs only in some of the questions but delivers the same estimates.

I am a 49 year-old female with no pre-existing health conditions of note and am not obese. My daughter is a 19 year-old female with no pre-existing health conditions of note and is not obese. We ran the QCovid risk calculator in summer 2020 when considering the risk posed to ourselves and therefore the potential benefit of a vaccine.  My risk of dying was one in 62,000 or 0.0016% and my risk of hospitalisation was one in 4,000 or 0.025%. My daughter’s risk of dying was one in 500,000 or 0.0002%. This data must have related to the variants around at the time although the risk calculator never made that clear.  

I checked the risk calculator again multiple times over the past 18 months and it had not changed (or possibly was not updated).  

I checked again on January 11th 2022 and the calculator has changed. The questions are the same, but the data generated is different. 

  1. You can now select whether or not you are vaccinated – however it doesn’t ask which vaccine you might have had, or indeed when it was delivered. We now know this makes a difference. It also doesn’t make any reference to the number of doses. This also makes a difference.
  2. The risk assessment doesn’t delineate between variants and we know Omicron is significantly less harmful than Delta or Alpha.  Are they suggesting the risk posed to my health is equivalent?

I have a BSc in medical biochemistry and a Masters in law; I am analytical and data driven – I spend my days reviewing data, searching for patterns and loopholes. I am not a mathematician, but something about the data the calculator is now offering doesn’t feel right. The estimates provided by QCovid for both people (mother and daughter) are below, vaccinated and unvaccinated:

Does the Oxford Study on Post-Vaccine Myocarditis Underestimate the Risk?

There follows a guest post by Daily Sceptic reader ‘Amanuensis’, as he’s known in the comments section, who is an ex-academic and senior Government researcher/scientist with experience in the field (find his blog here). He has taken a closer look at the recent papers from Oxford University on post-vaccine myocarditis risk and has some concerns about the methodology they have used which he suspects may underestimate the risk.

A few days ago the Daily Sceptic published an article on the risks of post-vaccination myocarditis, taking data from a recent paper by Julia Hippisley-Cox of Oxford University. This is a hot topic as myocarditis appears to have become the poster-child of vaccine side effects in the young, and any scientific papers that attempt to quantify the risk of myocarditis seem to get rather a lot of attention. Hippisley-Cox’s recent paper is no different.

Unfortunately, Hippisley-Cox et al appears to have used its method of choice, the Self-Controlled Case Series (SCCS), inappropriately. This is a bit of a grand statement given that Julia Hippisley-Cox’s papers are published in Nature Medicine, a very reputable journal – I’ll explain why the method has been used inappropriately and perhaps you might agree with me.

The self-controlled case series experimental design is quite simple in concept – there’s always a risk in experiments that your experimental group (the ones that we did things to) are different from the control group (the ones that were left alone), so in SCCS you simply use the same people for the experiment group and control group. In this particular example the magic happens by allocating a time for the vaccine side effects and stating that outside of this time the vaccine risk was zero – thus each experimental participant automatically sits in both the control group and experimental group.

There’s a nuance in the way SCCS is done for the Covid vaccine trials, in that there’ll often be a period before each treatment that is set aside and not used in the data analysis – the stated reason for this is because ill people are less likely to get vaccinated. I’ll come back to this point later, but for now just remember that there’s a pre-vaccine period that is separated out from the other data.

So, just to get up to speed on the sort of thing that you’d see with SCCS, I’ve made up a ‘perfect example’ of how SCCS might be used. In the following graph the number of side effects are indicated by little red dots – there are a low level of side effects before vaccination which then increase during the week after vaccination and then a gradual return to the baseline:

Major Oxford Study into Vaccine Side-Effects Finds Myocarditis Risk in Younger Males Up to 14 Times Higher After Vaccination Than After Infection

A major study from the University of Oxford into risks of myocarditis (heart inflammation) following Covid vaccination has found the risk in males under 40 to be significantly higher than the risk of the condition following Covid infection.

The researchers found that while there were seven additional myocarditis events per million in the 28 days following COVID-19 infection (95% Confidence Interval (CI): 2, 11), there were 14 following an AstraZeneca second dose (CI: 8,17), 12 following a Pfizer second dose (CI: 1,7), 101 following a Moderna second dose (CI: 95,104), and 13 following a Pfizer third dose (CI: 7,15). These findings are depicted above. Most of these figures represent a doubling of the risk compared with infection. However, the Moderna second dose figure is a massive 14.4 times greater. The Moderna vaccine uses a similar mRNA technology to the Pfizer vaccine, but delivers a dose three times as large, which may partly explain the difference.

For females and for males over 40 the study found greater risk of myocarditis following infection than following vaccination. However, some have criticised the study for under-counting Covid infections by using positive tests rather than antibody surveys, which means the risk following infection may be exaggerated. Another criticism was the use of only two age bands – above and below 40 years – which may conceal elevated risks for younger age groups. A third criticism is that by comparing the risk after infection to the risk after vaccination the study does not allow for the fact that many of the vaccinated will subsequently be infected anyway and experience both risks.

The study, which is a pre-print, is an update to an earlier study published in Nature earlier in December which used data up to August 24th. The update brings us up to November 15th, extends the age range down to 13 years from 16 years, and also includes results split by both sex and age (rather than just by sex and age separately) – the original study was especially criticised for omitting this breakdown, leading to allegations of concealing important findings for political purposes.

The authors note: “These findings have important implications for public health and vaccination policy.”

Indeed they do. In particular, given the low risk of Covid to males under 40, the extreme elevated risk of myocarditis from the Moderna vaccine means it ought to be suspended for use in males under 40 with immediate effect.

Image credit: Dr Tracy Høeg.

Covid Rules at University of Oxford to Remain Unchanged After July 19th

The number of settings in which life will continue as it is now after ‘Freedom Day’ keeps growing. Most recently, students at the University of Oxford have been told that rules on mask-wearing and social distancing will remain unchanged after July 19th due to high infection rates in the county.

The number of positive Covid tests in Oxford has been on the up in recent weeks, but deaths remain low, with zero deaths having been recorded in seven of the last 10 weeks and no more than three deaths recorded in the other three weeks.

Graph from Oxfordshire County Council.

University leaders haven’t let this stop them imposing tough lockdown restrictions. In an email sent to staff and students on Tuesday (and kindly forwarded to us at Lockdown Sceptics by a reader), Baroness Royall of Blaisdon, the Principal of Somerville College, said measures would remain “until further notice”.

Please note that, whilst the Government has confirmed plans to lift Covid restrictions on Monday, July 19th, the University’s policies on social distancing, face coverings and working from home will not change due to the high rates of Covid in Oxford. We will therefore continue with our Covid restrictions in College until further notice and, for the moment, we will not be allowing visitors.

On its website, the University warns that “Covid remains a real threat to many people in our community and… the pandemic is not yet over”. Students are instructed to continue following these measures:

  • Continue social distancing – assume two metres within University buildings unless told otherwise.
  • Keep washing your hands.
  • Keep wearing a face covering (unless you’re exempt).
  • Get tested – twice a week, with Lateral Flow Devices (LFDs); and take a PCR test if you have symptoms or have received a positive LFD test result or have been advised that you are a close contact of someone who has a PCR-confirmed case of Covid.
  • Continue to follow the self-isolation guidance.

If we can’t banish these restrictions from one of the country’s – the world’s – most learned institutions, what chance have we got of scrapping them from pubs and restaurants?

Ivermectin: Oxford University to Trial Promising, Easily Available Drug as Early Treatment for COVID-19

The Principle trial at the University of Oxford has selected Ivermectin for inclusion in its study of repurposed drugs for treatment of COVID-19. It will be given to people with Covid symptoms to see if it can keep them out of hospital. The BBC has the story.

The Principle study will compare those given the drug to patients receiving the usual NHS care.

The drug has become controversial after being promoted for use across Latin America and in South Africa, despite being so far unproven.

Previous studies of Ivermectin have generally been small or low quality.

Most commonly used to treat parasitic infections such as river blindness, spread by flies, Ivermectin has also been shown to kill viruses in petri dishes in the lab – although, at much higher doses than would usually be prescribed to people.

Ivermectin has been championed by many doctors and scientists since its apparent effectiveness as a Covid treatment emerged early in April 2020, but has been snubbed by mainstream health bodies for reasons that are unclear, leading some to suspect ulterior motives such as sustaining a vaccine narrative or prioritising newer and more profitable treatments. Merck, which manufactures Ivermectin but also recently signed a $356 million deal to supply the US with a much more expensive, experimental anti-Covid drug, went so far as to issue a statement casting doubt on the drug’s safety, even though its safety profile is well known and mild. Scientists trying to publish studies on the drug found the door being shut in their faces with apparent political motives for the refusal. Finally in May, the American Journal of Therapeutics published a peer-reviewed article by Dr Pierre Kory and colleagues entitled “Review of the Emerging Evidence Demonstrating the Efficacy of Ivermectin in the Prophylaxis and Treatment of COVID-19“. Dr Tess Lawrie and colleagues’ meta-analysis, finding a 62% reduction in risk of death among those infected or at high risk of Covid infection (on moderate-certainty evidence), was published in the same journal last week.

While, in a pandemic, the precautionary principle would seem to recommend authorising the use of safe, repurposed drugs that (small) trials have shown appear to work, health authorities apparently did not agree and said there must be higher quality evidence for Ivermectin before it can be approved. Yet because there is little profit in a cheap, out-of-patent drug these higher quality trials have not been done, leaving the drug still without approval or definitive evaluation over 14 months after its apparent efficacy against COVID-19 was discovered. If it does turn out to be as highly effective as the early studies suggest, this will mean the delay will have been responsible for failing to prevent many thousands of deaths around the world.

Still, better late than never, and credit to Oxford for including it in its study despite the politics around it. The Principle trial should provide the definitive answer as to whether Ivermectin is effective at preventing the progression to serious coronavirus disease when used at an early stage.

People aged 18-64 with an underlying health condition or experiencing breathlessness, and anyone aged 65 or over, can sign up to the Principle trial within 14 days of having Covid symptoms or receiving a positive test.

Official: Covid Pandemic Over in Britain

With the ONS reporting today that the number of people infected with COVID-19 in England has fallen to its lowest level since September, researchers at Oxford have said the vaccines are so effective that the UK is no longer in the midst of a pandemic. Sarah Knapton, Science Editor of the Telegraph, has more.

In the first large real-world study of the impact of vaccination on the general population, researchers found that the rollout is having a major impact on cutting both symptomatic and asymptomatic cases.

Sarah Walker, Professor of Medical Statistics and Epidemiology at Oxford and Chief Investigator on the Office for National Statistics COVID-19 Infection Survey, said that Britain had “moved from a pandemic to an endemic situation” where the virus is circulating at a low, largely controllable level in the community.

The new research, based on throat swabs from 373,402 people between December 1st last year and April 3rd, found three weeks after one dose of either the Pfizer or AstraZeneca jab, symptomatic infections fell by 74% and infections without symptoms by 57%.

By two doses, asymptomatic infections were down 70% and symptomatic by 90%.

It comes as infections continue to fall in Britain, dropping 7% in a week, despite the reopening of schools and shops. Deaths have also fallen by 26% and admissions by 19% over the last seven days.

New data from the ONS also showed that Covid was no longer the leading cause of death in March, falling behind dementia and heart disease, for the first time since October.

Worth reading in full.

Stop Press: Just 6% of beds are now taken up by Covid patients at England’s busiest NHS Trust compared to 60% at peak of second wave, an analysis of NHS data by MailOnline shows.