Dr. John Campbell is an internet sensation, giving facts & data to help us navigate healthcare in the present day. The interview covers John’s development, work, rise to fame & what he would do to help get healthcare back in shape.
It has been one of the most enduring Covid conspiracy theories: that the ‘gold standard’ PCR tests used to diagnose the virus were picking up people who weren’t actually infected.
Some even suggested the swabs, which have been carried out more than 200 million times in the UK alone, may mistake common colds and flu for corona.
If either, or both, were true, it would mean many of these cases should never have been counted in the daily tally – that the ominous and all-too-familiar figure, which was used to inform decisions on lockdowns and other pandemic measures, was an over-count.
And many of those who were ‘pinged’ and forced to isolate as a contact of someone who tested positive – causing a huge strain on the economy – did so unnecessarily.
Such statements, it must be said, have been roundly dismissed by top experts. And those scientists willing to give credence such concerns have been shouted down on social media, accused of being ‘Covid-deniers’, and even sidelined by colleagues.
But could they have been right all along?
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”.
…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 per cent of people who were told they were positive had a cycle threshold value above 30. For one in 20, it was higher than 40.
Here are key facts and sources about the alleged “pandemic”, that will help you get a grasp on what has happened to the world since January 2020, and help you enlighten any of your friends who might be still trapped in the New Normal fog.
- The survival rate of “Covid” is over 99%
- There has been NO unusual excess mortality
- “Covid death” counts are artificially inflated
- The vast majority of covid deaths have serious comorbidities
- Average age of “Covid death” is greater than the average life expectancy.
- Covid mortality exactly mirrors the natural mortality curve
- There has been a massive increase in the use of “unlawful” DNRs
- Lockdowns do not prevent the spread of disease
- Lockdowns kill people
- Hospitals were never unusually over-burdened
- PCR tests were not designed to diagnose illness
- PCR Tests have a history of being inaccurate and unreliable
- The CT values of the PCR tests are too high
- The World Health Organization (Twice) Admitted PCR tests produced false positives
- The scientific basis for Covid tests is questionable
- The majority of Covid infections are “asymptomatic”
- There is very little evidence supporting the alleged danger of “asymptomatic transmission”
- Ventilation is NOT a treatment for respiratory viruses
- Ventilators killed people
- Masks don’t work
- Masks are bad for your health
- Masks are bad for the planet
- Covid “vaccines” are totally unprecedented
- Vaccines do not confer immunity or prevent transmission
- The vaccines were rushed and have unknown longterm effects
- Vaccine manufacturers have been granted legal indemnity should they cause harm
- The EU was preparing “vaccine passports” at least a YEAR before the pandemic began
- A “training exercise” predicted the pandemic just weeks before it started
- Since the beginning of 2020, the Flu has “disappeared”
- The elite have made fortunes during the pandemic
“Lockdowns,” the mass quarantine of both sick and healthy people, have never before been used for disease mitigation in the modern Western world. Previously, the strategy had been systematically ruled out by the pandemic plans of the World Health Organization (WHO) and by health experts of every developed nation. So how did we get here?
Combined with other studies, these data indicate that vaccinated and unvaccinated individuals infected with the Delta variant might transmit infection. Importantly, we show that infectious SARS-CoV-2 is frequently found even in vaccinated persons when specimen Ct values are low.
The CDC has put new policies in place which effectively created a tiered system of diagnosis. Meaning, from now on, unvaccinated people will find it much easier to be diagnosed with Covid19 than vaccinated people.
Person A has not been vaccinated. They test positive for Covid using a PCR test at 40 cycles and, despite having no symptoms, they are officially a “covid case”.
Person B has been vaccinated. They test positive at 28 cycles, and spend six weeks bedridden with a high fever. Because they never went into a hospital and didn’t die they are NOT a Covid case.
Person C, who was also vaccinated, did die. After weeks in hospital with a high fever and respiratory problems. Only their positive PCR test was 29 cycles, so they’re not officially a Covid case either.
“We have to stop the nonsense. We have entered a vicious cycle. With every new wave, we’re starting a new wave of lockdowns. The lockdowns are creating a new virus. Then we have a new epidemic. We’re starting a new lockdown that creates a new virus.”
To guard against censorship, a transcript from https://dryburgh.com has been archived below. Please visit the source in the following link: https://dryburgh.com/knut-wittkowski-lockdowns-are-creating-a-new-virus/
Dr Knut Wittkowski
Dr. Wittkowski received his PhD in computer science from the University of Stuttgart and his ScD in Medical Biometry from the Eberhard Karls University of Tübingen, both Germany. He worked for 15 years with Klaus Dietz, a leading epidemiologist who coined the term “reproduction number”, on the Epidemiology of HIV before. Around 1990, he was one of the few to predict that HIV would not spread among Caucasian heterosexuals. After teaching epidemiology at the University of Cairo and the American University of Beirut, he was for 20 years head of Biostatistics, Epidemiology, and Research Design at The Rockefeller University, New York.
Dr. Wittkowski is currently the CEO of ASDERA LLC, a company discovering novel interventions against complex diseases from data of genome-wide association studies, including a nutritional intervention to reduce cellular support for virus replication and to improve cardiovascular and metabolic health as a natural strategy to reduce the burden and stop the continuation of the COVID epidemics.
- March 23rd, AP News: Chancellor of Germany Angela Merkel “We basically have a new pandemic. Essentially we have a new virus, obviously of the same type but with completely different characteristics. Significantly more deadly, significantly more infectious, and infectious for longer.” (Germany extends virus lockdown till mid-April as cases rise)
Host ➝ 00:00
Welcome. Today it’s for anyone who may or may not know me, I am Tania The Herbalist, and today I have the privilege of talking and chatting with Knut Wittkowski. Knut is not any medical expert, actually. He’s got a master’s in biostatistics, a PhD in computer science, a doctor of science and medical biometry, including genetics and epidemiology. And you were former head of research, design and biostatistics at the Rockefeller Foundation.
Knut Wittkowski ➝ 00:36
And epidemiology at the Rockefeller University here in New York.
Host ➝ 00:42
Beautiful. Thank you for that. Well, you now have gone viral because of your expertise and your many articles and especially one of your most recent ones about how much lockdown policy does not actually agree with the established epidemiological policy. Because, of course, we know the experts controlling the local policy are motivated by fear and politics. Can you talk about that a little bit for us?
Knut Wittkowski ➝ 01:12
If we go back one year and if you still remember the reason for having a lockdown, people were afraid that the situation in the US, and in particular in New York, at the time would become as dire as in the North of Italy where the hospital system was totally overwhelmed.
And one could understand that even though I didn’t share that fear, but I could understand it. But a month later we had the data from the CDC that there would never be a major problem.
The hospital ship that had anchored in New York left. The Javits center, the conference center that had 2000 beds, was never used. The tents in Central Park put up by Mount Sinai hospital, also not used.
There was a shortage here and there, once in a while, but there was no, not even close to the hospital system collapsing.
So one could have reopened and said, well, it was three, four weeks, too bad. We were overly pessimistic, overly careful, but everybody would have understood that was erring on the side of caution.
Knut Wittkowski ➝ 02:52
And then suddenly the game posts shifted. It was not anymore about the hospital system collapsing. Today it’s not either.
We have currently something like less than 15% of all hospital utilization is due to COVID. That is noticeable, but it doesn’t mean that there is a major problem.
Again, there may be a local problem here or there, but that is not, should not be enough to run the whole economy against the wall.
So it became somewhat unclear what the objective of the lockdown should be. Should it be that the country should be locked down until there is no single virus around anymore? Somehow nobody actually explained that. Why should we control the virus? Why should we stop the spread? And could we?
Host ➝ 04:11
Right. So, from your expertise, what is the difference between COVID and influenza?
Knut Wittkowski ➝ 04:22
If we had not the tools to sequence the virus and had learned in late December  or early January , I forgot when it was, that this happened to be a coronavirus, one of those that hit us every now and then, rather than influenza virus that hits us a bit more frequently, we would not have seen any difference between this and the epidemic, for instance, of 2017/2018, which was also a bad flu.
Host ➝ 04:59
Right. And now if we let it run its course the way we do other viruses, how long do you think it would actually be before we could reach herd immunity?
Knut Wittkowski ➝ 05:08
It will take about six weeks and can be shifted a bit in different parts of the country, depending on where the virus gets there [“endemic equilibrium herd immunity”].
So it was here in New York earlier, and the epidemic ended even before the lockdowns started. I mean, that infections went down before the lockdown started. It came later in the South.
So in the South, we have seen the effect of flattening the curve. You are delaying the infections and illnesses and death for a couple of months until you reopen. And then the delayed events happen because lockdowns do not prevent anything from happening. They just delay it a bit.
Host ➝ 05:59
Is there any scientific background behind lockdowns?
Knut Wittkowski ➝ 06:04
Nobody has ever done a lockdown for any disease. So it was not quite clear how this experiment would end.
Host ➝ 06:16
Right, right. And so many are actually are, sorry, go ahead.
Knut Wittkowski ➝ 06:22
And what we saw was that it backfired in many ways. So one thing that we have seen, and we know since October, when the viruses in Spain and France had been sequenced, we know that because of the lockdowns giving the virus enough time to mutate, we had escape mutations that started the wave in November. So we are currently experiencing the result of the lockdowns. Without lockdowns, we would not have any COVID right now.
Host ➝ 07:06
Right. And it’s funny because many seem to argue that the lockdown measures is actually what decreased the potential mortalities that could have happened if it wasn’t for these measures. So really, how effective are the measures like social distancing, isolation, things like that.
Knut Wittkowski ➝ 07:22
They’re very effective. They have cost many jobs and the economy a lot of money. So they were very effective [sarcasm].
Host ➝ 07:32
Right, right. And here in Ontario, I’m in Canada in Ontario here, we’ve now got a stay at home order. So, you know, even things like going to bargaining and skating and things like that outdoors, they’re almost saying, don’t do, stay at home. Only leave for essentials
Knut Wittkowski ➝ 07:51
Because otherwise, we need that [restrictions breeding variants] urgently, because otherwise we run the risk that there will be no new epidemic in a few months [sarcasm]. Because the lockdowns are essential for the virus to develop new strains.
“because of the lockdowns giving the virus enough time to mutate, we had escape mutations that started the wave in November. So we are currently experiencing the result of the lockdowns. Without lockdowns, we would not have any COVID right now.”
Our immune system develops typically something like five or six different types of antibodies to protect us from mutations that might happen while we are infected to make sure that even if there is a mutation in one of the epitopes, the targets of the antibodies, if there is a mutation, then there should be other antibodies that still are sufficient to prevent the virus from being replicated and from spreading.
However, if you give the long enough and the virus mutates at a rate of one or two mutations a month. So if you give it three months, there’s a good chance that there will be six consecutive mutations, one for each of these antibodies.
And at the end, the human immunity does not capture the virus anymore. And the virus can spread.
We have, even though it’s technically mostly the same virus, but experience as if it were a totally new virus. And this is what we’re seeing right now.
“Nobody has ever done a lockdown for any disease. So it was not quite clear how this experiment would end.”
What we have seen since November is a new virus, or actually a family of new viruses, because similar things happened in Spain and France and in the UK and in South Africa and also in the United States. So it’s a very… the common thing, if you give the virus enough time with the lockdowns, it will mutate and you have the next epidemic.
Host ➝ 09:51
Right. And how important is it for us to be outdoors and being with nature and being outside and getting fresh air? Because I think a stay at home orders, I believe could be obviously detrimental, especially for the healthy and the young and children.
Knut Wittkowski ➝ 10:07
I mean, I don’t want to go there. It’s too frustrating to see a whole generation of children being deprived of their wellbeing and their development.
The children can not, it’s immunologically dramatic, because they cannot develop the immune responses that they need for the rest of their life.
They don’t have the social contacts that they have in school. They don’t learn.
If you’re taking away one year in the development – and it’s now getting more than that – one year in the development of a child that’s below the age of 10, you’re creating a huge gap and you’re preventing this child from having all the opportunities that they otherwise would have. And the tragic thing here is that there is no reason for it.
Children do not get ill – with very rare exceptions.
Yes, we have had in the United States, something like – I haven’t checked the last week.
So maybe it’s 30 deaths in children from age four to age fourteen. Thirty. We had over 50 from influenza during the same time period. Yes. It happens with every flu, a few children die. And I feel sorry for the families who are affected. For them, it’s a tragedy.
However, should we close down the country of 335 million people in the US, a bit less in Canada, but should we destroy the life of hundreds of millions of people, because there is a risk for some children. And most of these children who die have co-morbidities, have diabetes, have other diseases, other immune diseases. The balance, this is totally out of balance.
Host ➝ 12:51
Yeah. And at what point in time did you realize that these measures are going to kill more people than prevent?
Knut Wittkowski ➝ 13:01
That was known from the very beginning because the measures do not reduce COVID deaths, but they’re causing lots of others.
And so we knew from the very beginning that there would be more deaths because of the lockdowns, unless we are counting the risk that the hospital system would collapse and then we would have many deaths for other reasons.
But as soon as it was clear that the hospital system would not be collapsing – and it still is not collapsing – the lockdowns should have ended.
And the schools should never have been closed, because children, except for the very rare exceptions, don’t develop any severe illness. So they will not end up in a hospital.
Even the young adults don’t end up in hospitals in relevant numbers. We knew that 50% of all people who died, many of them in hospitals, were older than 80 years.
So if you are below the age of 60, your risk of having a severe disease or even dying is irrelevant. I mean, when we cross the street, we can always be hit by a brick and still not everybody wears hard hat all the time, because there is a theoretical risk that you may be hit by a brick.
And here, for those under the age of 60, about, it is a theoretical risk, like the many theoretical risks that we are facing every day in our life.
“That was known from the very beginning because the measures do not reduce COVID deaths, but they’re causing lots of others.”
And we have to take risks because otherwise we couldn’t live. And that’s what we have right now. We cannot live.
Host ➝ 15:17
Now. I have to ask you, how is the data for COVID being collected now in comparison to previous respiratory infections?
Knut Wittkowski ➝ 15:29
I have been working many years ago on HIV when I predicted correctly that HIV would never spread among the Caucasian heterosexual population, which at that time, politicians and media were very scared of. They thought all of Europe and the United States would become depopulated because of HIV. Didn’t happen.
But there actually, the reporting was good. We knew for every case and then “case” meant you have the disease, you have a problem. So for every case, it was reported, when was it diagnosed, and when was it reported.
So these days, the difference were there. And as epidemiologists, we could use that to make more sense of the data and the definitions were not changed all the time [unlike with COVID-19].
I just learned today that it seems that PCR, the definition of what a positive PCR test is, is being changed from running for 35 cycles to only running for 25 cycles, which makes the test less sensitive.
And then of course, we know that the vaccines are working [sarcasm] because there are fewer infections, except at the same time, the test was changed.
And we had had so many changes. What is a “case”? A case traditionally is somebody who has an illness, and then you find out why that person is ill.
Right now you have people who want to travel or have a job requirement. So they’re standing here on the street to get tested. And if they happened to get tested positive, they are called a case. They’re not ill, they probably will never be. They may not even be infected. They may just have some virus sitting in the nose that never got into the body. And you call them cases? Everything in this epidemic is done upside down. It almost feels like people want to obscure what’s going on because we know that during an epidemic, you don’t change the measures that you take, because then you cannot compare it anymore. And here it happens all the time, which is frustrating.
Host ➝ 18:28
Now I have to ask you because of course I admire your courage and you speaking out against this, but why do you find that more medical experts are not speaking about this, especially when you hear about MDs and even some neurologists, but you’re never hearing about a virologist or an epidemiologist that are really speaking out on this, which, like yourself, are the best people.
Knut Wittkowski ➝ 18:50
We have three virologists speaking out in the United States and only virologists. Different areas of science have different objectives. And people are trained for doing different things.
“Everything in this epidemic is done upside down. It almost feels like people want to obscure what’s going on”
An MD is trained to make a diagnosis with an individual patient, find the treatment, convince the patient that he or she should take the treatment, follow up and see how it works. This is by and large, what an MD is treated to do.
A virologist studies the structure of the virus. What is it composed of and where does it bind? And how does the cell with the virus binds, interact with the cell? How can, what would be potential vaccine? How, what structure, what epitopes would we use? Things like that.
And then there are epidemiologists who study how does the virus spread? What is the most effective thing to do against the spread of the virus? These questions, no MD and no virologist is trained to deal with these questions because you need mathematical models. You need a lot of experience in dealing with large sets of data, and that is something what epidemiologists do, and they were not heard in March or April.
Host ➝ 20:40
Now, one of the last questions that I have to ask you, of course, just to kind of give people a little bit of light because many are starting wake up more and more about the lockdowns kind of being worse than the disease itself, because there’s a lot of implications. What do you think is the proper solution to handle this virus? If you had the option, what’s your solution.
Knut Wittkowski ➝ 20:59
Okay. The first thing you already said, let’s reopen schools and the economy. There’s no reason to keep them closed.
Of course, masks can be helpful when worn by those who are vulnerable, and let’s presume masks are effective, and we’re still not quite sure whether they are, but let’s presume that they’re effective. And this would be one of the strategies, the vulnerable, those who have comorbidities and are older can use to pre-protect themselves, to self isolate while the virus is running among the low risk people and taking its natural course, which will have very few severe events and very few deaths. Because as I said, it is mostly the elderly who die.
So masks should be worn by those who are vulnerable and by the people who directly interact with the vulnerable, because if you are helping somebody from the wheelchair into the beds, or the other way around there is physical interactions and close proximity. And these are situations where the risk of transmission is highest. And so to help the elderly or the vulnerable to self isolate, those directly interacting with them should wear a mask.
And also, if possible, try to distance a bit. Everybody else should not because if everybody else does the same thing, then the vulnerable wouldn’t have an advantage anymore. The virus would spread a bit more slowly overall. It would spread at the same rate among the elderly and vulnerable as among the young and healthy.
So if everybody wears a mask and does other ways of distancing, we are increasing the number of deaths.
So just to put the numbers that we have in context. In the United States, we had so far about 400,000 deaths, 200,000 were from COVID-20, since November, which would not have been here without lockdowns.
Knut Wittkowski ➝ 23:42
And then among those among 200,000, 40% were in nursing homes. Now the nursing homes – we’ve been talking about protecting the vulnerable. If the vulnerable had been protected better, there would have been much fewer deaths. There may have been about a hundred thousand. A hundred thousand deaths is normal for a flu. It’s at the upper end, but this is nothing unusual for flu.
So we should keep everything open and we should focus on the things that are really dangerous. It’s not dangerous to be coughing or sneezing for a few days while you have a flu or even COVID like many people have.
It gets dangerous when you end up in the hospital, in the emergency room and then you may die. So we have to prevent that. And now I’m talking a bit pro domo. My company is working on something like that. One of these strategies where we are giving people the option to prevent, to reduce their comorbidities.
And without comorbidities, almost nobody dies.
Knut Wittkowski ➝ 25:16
And also to reduce the rate by which the virus spreads in the body, within the body. Because we are not dying of the virus itself. We could live with that virus forever. It would produce a couple of viruses on the side, but that’s not a big deal.
“There may have been about a hundred thousand. A hundred thousand deaths is normal for a flu. It’s at the upper end, but this is nothing unusual for flu.”
What we are dying off is the immune system. When it has the antibodies. After one week of incubation time, the immune system kills all infected cells. And if many cells are infected, like in the lung, then a large part of the lung cells are being killed. Now that’s causing a problem. If people are young and healthy, they can live with it. If they’re old and a bit fragile, that huge wound is killing them. So it’s the reaction of the immune system to the virus that’s killing. And that depends, how dangerous it is, depends on the viral load.
Knut Wittkowski ➝ 26:26
So when we can reduce the rate by which the virus replicates it’s by only 10%, then for every seven hour replication cycle. Then after the five days, we have reduced the number of cells that became infected by about 80 to 90%. And then the wound created by the immune system is much smaller and everybody survives it.
So we should not close down schools and the economy, we should focus on helping the elderly and vulnerable to self isolate. And we should also focus on dealing with the one problem that is really important, and that is preparing the immune system better to deal with that infection in a natural way so that the disease is not so severe. And if the disease is not so severe, then what are we talking about?
We are not closing the country down for the common cold. And if we succeed in reducing the severity of that disease to that of a common cold, and I think that is possible. And even if it were to the severity of a regular flu, then why do we need to lock down?
Host ➝ 28:07
All right. Thank you for that information, Knut. Is there anything else that you would want to add to any of this?
Knut Wittkowski ➝ 28:20
I think we covered most of the things. The advice to our politicians is very simple. I am not the only one. If you think of the Great Barrington Declaration that has been signed now by over a million scientists.
Knut Wittkowski ➝ 28:45
We have to stop the nonsense. We have entered a vicious cycle. With every new wave, we’re starting a new wave of lockdowns. The lockdowns are creating a new virus. Then we have a new epidemic. We’re starting a new lockdown that creates a new virus.
Einstein defined the word insanity, and said, insanity is doing the same thing over and over again, and expecting different results. Doing lockdowns over and over again will have no other results than creating the viruses that are capable of starting a new epidemic. And then we are exactly at the point where we were before.
Although it may be a bit worse because the new virus may also be resistant against some of the cross immunity that we already had from other coronavirus infections. So we may need more people to get infected, to get over the next virus.
Knut Wittkowski ➝ 30:13
And then I have one fear.
And that is that every new generation of viruses here, the virus genome gets closer and closer to the human genome because our immune system can make antibodies only against stretches of genetic information on the genome that are unique to the virus.
And just a couple of weeks ago, three weeks or so, a paper was published and there it said less than 10% of the virus genome is available for the immune system to make antibodies against it. And then every generation, the virus mutates and becomes a bit closer to something that is already in the human genome. And then it becomes more and more difficult for the immune system to make antibodies. This situation has never arrised in the whole history of humankind. The lockdowns are creating a problem that has never existed. And for which nature did not find a solution. We should let nature do it. We should adjust. We should adapt. But we should not think that we can control nature.
Knut Wittkowski ➝ 32:06
My first name is Knut, and I had a namesake in the 11th century, more or less exactly a thousand years ago. And he got annoyed by people thinking he was so powerful he could do anything.
And so he walked to the beach and told the tide to stay away. Just to show that nature was much more powerful than even the most powerful King at the time. Of course the tide didn’t stay away.
“With every new wave, we’re starting a new wave of lockdowns. The lockdowns are creating a new virus. Then we have a new epidemic.”
Now, since then, during the last 1000 years, I don’t think there was a single politician who would have said nature is more powerful than I am. Politicians think they know everything better, everything better than nature. And they can control a virus like the tide. We cannot control the tide and we can not control a virus. We can only make it worse.
Host ➝ 33:25
Very well said, very well said. It’s true. Let nature run its course is really the ultimate thing that we can do for proper herd immunity and getting back to some form of normalcy. So I appreciate your wisdom. I appreciate your words. And I appreciate your work, Knut. Where can people find you if they want to connect with you on your website? I don’t know if you’re on social media, where can they connect with you more?
Knut Wittkowski ➝ 33:51
My name is unique. If you look for Knut Wittkowski, you will find me.
“We have to stop the nonsense. We have entered a vicious cycle. With every new wave, we’re starting a new wave of lockdowns. The lockdowns are creating a new virus. Then we have a new epidemic. We’re starting a new lockdown that creates a new virus.”
Host ➝ 34:00
Right. And, of course, your website is asdera.com. You’ve got lots of information there. So anyone who’s looking for it, interviews, articles, everything that you’ve done.
Knut Wittkowski ➝ 34:18
I will put this there too, as soon as it gets published. So thank you, Tania.
Host ➝ 34:25
Well, thank you so much for your time. Thank you. I appreciate it. And we’ll do this again hopefully soon sometime. Thank you.
Note: The WHO acknowledges the problems of false positives due to inappropriate cycle threshold used in PCR testing.
WHO guidance Diagnostic testing for SARS-CoV-2 states that careful interpretation of weak positive results is needed (1). The cycle threshold (Ct) needed to detect virus is inversely proportional to the patient’s viral load. Where test results do not correspond with the clinical presentation, a new specimen should be taken and retested using the same or different NAT technology.
WHO reminds IVD users that disease prevalence alters the predictive value of test results; as disease prevalence decreases, the risk of false positive increases (2). This means that the probability that a person who has a positive result (SARS-CoV-2 detected) is truly infected with SARS-CoV-2 decreases as prevalence decreases, irrespective of the claimed specificity.
Most PCR assays are indicated as an aid for diagnosis, therefore, health care providers must consider any result in combination with timing of sampling, specimen type, assay specifics, clinical observations, patient history, confirmed status of any contacts, and epidemiological information.
WHO has received user feedback on an elevated risk for false SARS-CoV-2 results when testing specimens using RT-PCR reagents on open systems.
As with any diagnostic procedure, the positive and negative predictive values for the product in a given testing population are important to note. As the positivity rate for SARS-CoV-2 decreases, the positive predictive value also decreases. This means that the probability that a person who has a positive result (SARS-CoV-2 detected) is truly infected with SARS-CoV-2 decreases as positivity rate decreases, irrespective of the assay specificity. Therefore, healthcare providers are encouraged to take into consideration testing results along with clinical signs and symptoms, confirmed status of any contacts, etc.