Masks Revisited and Covid Tests Reliability

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In this article I want to revisit an issue I addressed in detail previously and address an issue I have only touched on briefly previously.

Masks Revisited

I wrote a three-part article on masks back in October 2020. It was titled, Does a Mask Protect the Wearer from the Coronavirus? The answer to the title question was “Yes,” but with some caveats.

Caveats:

The main caveat was that protection was not to prevent infection but to reduce the viral load by which someone is infected. That would in turn reduce the severity of the resultant illness.

An additional caveat was that the mask had to be worn properly. That included the mask covering both the mouth and nose, the mask fitting properly, with it formed around the top of the nose with the little metal strip in the mask, not fiddling with it, that a mask is only worn once then washed or discarded, and that it is carefully handled if taken off and put back on.

Finally, I documented that cloth masks were much less effective than surgical and N95 masks, while the N95 masks were only slightly more effective than surgical masks. As such, only the latter two should be worn.

I cautioned back then to not trust any study that might come out that did not account for all of these factors. Since then, many studies on masks have been conducted and published. And conservatives have proudly proclaimed they were correct, that mask are useless at preventing transmission of the Covid virus. However, that very proclamation shows my first caveat was not followed. And if you look at the studies, they are not even saying that much.

Cochrane Masks Study:

One of the most touted studies by the right was the Cochrane study, a meta-analysis of 78 studies. Its main conclusion was, “States with mask mandates fared no better against Covid than those without” (NYT. The Mask).

Right-wing news outlet Just the News titled their article about the study, “‘Little to no difference’: Massive mask meta-study undermines remaining COVID mandates.” The title of the article by the liberal New York Times about it was, “The Mask Mandates Did Nothing.”

Right-wingers jumped from those correct summaries of the study to proclaiming, “Masks don’t work.” However, there is a huge difference between saying masks mandates don’t work and saying masks don’t work. The NYT comments in that article:

No study — or study of studies — is ever perfect. Science is never absolutely settled. What’s more, the analysis does not prove that proper masks, properly worn, had no benefit at an individual level. People may have good personal reasons to wear masks, and they may have the discipline to wear them consistently. Their choices are their own.

But when it comes to the population-level benefits of masking, the verdict is in: Mask mandates were a bust.….

Yet there was never a chance that mask mandates in the United States would get anywhere close to 100 percent compliance or that people would or could wear masks in a way that would meaningfully reduce transmission. Part of the reason is specific to American habits and culture, part of it to constitutional limits on government power, part of it to human nature, part of it to competing social and economic necessities, part of it to the evolution of the virus itself (NYT. The Mask).

The study itself cautions:

The observed lack of effect of mask wearing in interrupting the spread of influenza‐like illness (ILI) or influenza/COVID‐19 in our review has many potential reasons, including: poor study design; insufficiently powered studies arising from low viral circulation in some studies; lower adherence with mask wearing, especially amongst children; quality of the masks used; self‐contamination of the mask by hands; lack of protection from eye exposure from respiratory droplets (allowing a route of entry of respiratory viruses into the nose via the lacrimal duct); saturation of masks with saliva from extended use (promoting virus survival in proteinaceous material); and possible risk compensation behaviour leading to an exaggerated sense of security….

The type of fabric and weave used in the face mask is an equally pressing concern, given that surgical masks with their cotton‐polypropylene fabric appear to be effective in the healthcare setting, but there are questions about the effectiveness of simple cotton masks.

The high risk of bias in the trials, variation in outcome measurement, and relatively low adherence with the interventions during the studies hampers drawing firm conclusions….

The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect (Chocrane. Physical).

In another article, the NYT comments on this study:

“Many commentators have claimed that a recently updated Cochrane Review shows that ‘masks don’t work’, which is an inaccurate and misleading interpretation,” Karla Soares-Weiser, the editor in chief of The Cochrane Library, said in a statement.

“The review examined whether interventions to promote mask wearing help to slow the spread of respiratory viruses,” Soares-Weiser said, adding, “given the limitations in the primary evidence, the review is not able to address the question of whether mask wearing itself reduces people’s risk of contracting or spreading respiratory viruses.”

She said that “this wording was open to misinterpretation, for which we apologize,” and that Cochrane would revise the summary. …

Michael D. Brown, a doctor and academic who serves on the Cochrane editorial board and made the final decision on the review, told me the review couldn’t arrive at a firm conclusion because there weren’t enough high-quality randomized trials with high rates of mask adherence….

Of those 10 studies that looked at masking, the two done since the start of the Covid pandemic both found that masks helped….

For example, in one study of hajj pilgrims in Mecca, only 24.7 percent of those assigned to wear masks reported using one daily, but not all the time (while 14.3 percent in the no-mask group wore one anyway). The pilgrims then slept together, generally in tents with 50 or 100 people. Not surprisingly, given there was little difference between the two groups, researchers found no difference from mask wearing and declared their results “inconclusive” (NYT. Here’s).

Summary:

To summarize the preceding quotes, the reason why this and related studies do not find a benefit on a population level for masks is not necessary because masks do not work at preventing transmission, but that people do not obey masks mandates.

In areas with masks mandates, there is low adherence in the wearing of masks and if people do wear them, they do not take it seriously. Consequently, they half-mask (cover the mouth but not the nose), they often have the mask hanging from one ear, they reuse the same mask over and over again without washing it in between, they are constantly fiddling with it, they are not careful in taking it off and putting it back on, they wear ill-fitting masks, and/ or they wear cloth masks rather than more effective surgical or N95 masks.

All of those problems result in the lack of effectiveness on a population basis. However, the studies themselves will often state that their results do not apply to the effectiveness of masks on an individual basis.

Also, do not miss the paragraph about there not being a significant difference between the rate of mask-wearing in an area with a mandate versus one without one. That is often the case in mask mandates, and it makes it impossible for the researchers to draw any conclusions on whether masks work or not. All they can say is mask mandates do not work.

By way of comparison, let’s you want to study if seat belts save lives. If all you do is compare the rate of deaths in car crashes in areas with seat belt laws versus ones without, then your study is worthless. The reason is, not everyone follows seat belt laws, and some people will still wear seat belts even if they are not mandated. You need to find out if the rate of compliance in the mandated area is greater than in the non-mandate area. It is the same with masks.

Simply put, many who do not believe mask work will not wear them even when mandated, or at least not wear them correctly, while many who believe masks work will still wear them even if not mandated to do so. As such, the best researchers can do is to conclude mask mandates do not work, while being unable to comment on the effectiveness of masks per se.

My Main Thesis and Mandates:

None of this even considers my main thesis in regard to masks that their main purpose is not to reduce transmission but the viral load by which someone is infected, thus reducing the severity of illness.

As such, my thesis on masks still holds. At least it would if it were not for the vaccines. Since they have the same benefit of reducing the risk of severe illness, then if someone is vaccinated and boosted as needed, then masks become superfluous.

At the very least, the wearing or non-wearing of masks should be an individual choice, not mandated. That is especially so given that these studies do reliably show that such mandates do not work for all of the stated reasons. You can mandate mask-wearing in general, but it is very difficult if not impossible to mandate proper mask-wearing.

Hand Hygiene

Before moving the next main topic of this article, I wanted to mention a side observation and conclusion of the Cochrane study:

Comparing hand hygiene interventions with controls (i.e. no intervention), there was a 14% relative reduction in the number of people with ARIs [acute respiratory infections] in the hand hygiene group (RR 0.86, 95% CI 0.81 to 0.90; 9 trials, 52,105 participants; moderate‐certainty evidence), suggesting a probable benefit. In absolute terms this benefit would result in a reduction from 380 events per 1000 people to 327 per 1000 people (95% CI 308 to 342)….

Our findings show that hand hygiene has a modest effect as a physical intervention to interrupt the spread of respiratory viruses, but several questions remain.

Thus, there is a benefit to being conscientious about hand washing. That recommendation of the authorities was correct. But it was always just that, a recommendation. It was never possible to mandate hand-washing, so that was never done. This confirms that when people choose to do something, they will be more conscientious about it than if they are mandated to do it.

The difference is, with a recommendation, the authorities need to explain why and how it should be done, to convince people to do it. But with a mandate, they just tell people to do it, with no explanation as to why or how to do it. I remember seeing on news reports segments about proper hand washing, but I never saw a segment on proper mask usage.

Are Covid Tests Reliable?

Many on the right deny that the Covid tests are reliable. They mostly claim they give false positives, indicating someone is infected when they are not. The claim is the tests are too sensitive and will indicate an infection when only a particle of the Covid virus is present. Or they claim the tests do not distinguish between the Covid virus and other viruses, like the influenza virus.

Tests Studies and Newer Tests:

However, articles with such claims generally only cite studies on Covid tests conducted in 2020. As I write this, it is the end of 2023, so more reliable tests are now available, and much more research has been done since then.

Those newer tests can distinguish between Covid and other viruses. In fact, earlier tests did not show positive if only the influenza virus was present. They simply showed negative, noting the lack of presence Covid but not noting the presence of influenza. Thus, they were accurate in showing negative for Covid. Newer tests indicate if someone is infected with one or the other virus.

Moreover, articles denying the reliability of Covid test are generally by individuals, while those documenting their reliability are generally by health organizations. I’ll let the reader decide which is more reliable, a lone doctor making claims or an organization with checks and balances.

False Negatives and Viral Load:

A positive result happens when the SARS-CoV-2 primers match the DNA in the sample and the sequence is amplified, creating millions of copies. This means the sample is from an infected individual. The primers only amplify genetic material from the virus, so it is unlikely a sample will be positive if viral RNA is not present. If it does, it is called a false positive.

A negative result happens when the SARS-CoV-2 primers do not match the genetic material in the sample and there is no amplification. This means the sample did not contain any virus (NIH. Systematic).

A false negative result happens when a person is infected, but there is not enough viral genetic material in the sample for the PCR test to detect it. This can happen early after a person is exposed. Overall, false negative results are much more likely than false positive results (NIH. Systematic, bolding in original).

If there is an inaccuracy, it is much more likely to be a false negative than a false positive. In other words, it is much more likely a test will not show positive the virus when it is present than to show positive when the virus is not present.

A false negative is most likely when someone is recently infected, within the previous day or two, but far less likely later in the illness.

The most accurate tests for the SARS-CoV-2 virus that causes COVID-19 use PCR to detect the presence of its unique RNA signature. This test is exquisitely accurate — a single copy of the virus in a test sample can be detected (ASU. Covid-19).

A positive COVID-19 PCR test means that SARS-CoV-2 is present. A negative result could either mean that the sample did not contain any virus or that there is too little viral genetic material in the sample to be detected (NIH. Systematic).

The right-wingers’ claim that the test shows positive even if a tiny particle of the virus is present is true. The PCR tests are very sensitive. Moreover, it is also true the tests do not indicate the amount of virus present. Thus, a person could test positive but not have been infected with a sufficient viral load to cause symptoms. That takes us back to my thesis on the role of masks and to the benefit of vaccines. In both cases, that viral load is reduced, and the risk of severe illness is decreased.

Contagious?

The main question is if someone who is infected with a small viral load is contagious. To put it another way, is someone with an asymptomatic Covid infection infectious? The answer is:

New research suggests that people without COVID-19 symptoms are much less likely to transmit the virus than those who display symptoms….

Experts stress that asymptomatic infections are not the same as the presymptomatic phase of COVID-19.

Before people exhibit symptoms or test positive for the coronavirus, they’re considered “presymptomatic” and can still pass the virus on to others—even if they don’t yet realize they are sick.

“In our review, people with presymptomatic infection were as likely to transmit the infection to close contacts as those who had symptoms at the time of diagnosis,” the researchers of the new study told Verywell via an email. “And people without any symptoms throughout the course of infection can still pass it on.”

That is why health experts recommend testing after a potential COVID exposure and isolating if you’re infected. Even if you don’t feel sick, it doesn’t mean you’re not infectious at all (Very Well Health. Study).

At least 40% of COVID-19 patients never develop symptoms at all but are just as infectious, and a further 25-30% with minor symptoms are unaware they have COVID-19. These two groups are rarely tested and therefore continue to expose others…

It takes 7-10,000 viral copies to infect one human cell. PCR’s greater accuracy detects viral load far below this level, and thus incorrectly identifies many individuals as infectious when they are not…

On the plus side, PCR is better at detecting the early hours of infection as the virus becomes established in a human host — the start of 4 days of peak infectivity. On that first day, viral load is exploding from undetectable to trillions of viral particles in hours. Even if a less accurate antigen test misses the early hours of infectivity, it will definitely catch all cases by later that first day and on all subsequent days of infectivity. Over the next five to 10 days as patients recover, viral load declines only slowly, so PCR continues to be positive throughout this period. This is a serious disadvantage because these PCR positive individuals are “false positives” in the sense they can no longer transmit the virus to others. Recent work carried out at Johns Hopkins on behalf of BD Life Sciences (a vendor of Veritor Plus, one of the approved antigen tests) clearly confirms that the “lower” sensitivity of antigen tests provides a much more “accurate” answer about infectivity than the “higher” sensitivity RT-PCR test.

PCR is just too sensitive to tell us accurately whether an individual’s breath has the capability to infect others. Antigen test sensitivity is more appropriate to identify those who need to be isolated to prevent ongoing transmission (ASU. Covid-19).

The PCR test is what right-wingers complain about being too sensitive. But the newer and quicker antigen tests are less sensitive. They only show a positive result when a significant viral load is present. Thus, if you test positive with an antigen test, you most definitely should self-isolate, as you are contagious.

However, you are less infectious if you have an asymptomatic infection than a symptomatic one. But there is no way early on to know if you will develop symptoms eventually, and even asymptomatic infected persons can still spread the virus, though they are less likely to do so. As such, any positive test needs to be taken seriously, and the person should still self-isolate until fully recovered.

Finally, note that at the start of the pandemic the recommendation was to self-isolate for ten days after testing positive even if asymptomatic. That was later reduced to just five days. The reason for the change is a person is only contagious for the first four days of an infection, with a day added for good measure. But there was no need to self-isolate for days 6-10 if the person no longer displays symptoms.

Covid Tests Are Reliable:

All of this means that the currently available Covid tests are reliable for their main purpose of letting someone know whether they should be self-isolating or not. If you test positive with an antigen test, you should. But where there is some uncertainty is with PCR tests, as they are, as right-wingers claim, a bit too sensitive and might have people self-isolating unnecessarily.

There is also the possibility of false negatives. Just because you test negative, you might still be carrying the virus. That means, if you came into contact with someone with a known Covid infection, you should still be cautious, especially around high-risk individuals, like the elderly.

Covid is Real:

COVID-19 PCR tests use primers that match a segment of the virus’s genetic material. This allows many copies of that material to be made, which can be used to detect whether or not the virus is present (NIH. Systematic).

One of the most ridiculous comments I received on social media was the claim that Covid tests don’t work because a Covid virus has never been identified, as there is no such thing as Covid. But these and a myriad of other quotes I could produce argue otherwise.

Yes, there is a Covid virus. Yes, it is real. And yes, Covid tests can detect that known Covid virus. Any claims otherwise are just plain silly.

As I said previously, if someone tests positive for Covid and has the symptoms of Covid, then they have Covid. You would think that would be unquestionable, but Covid deniers will even deny the presence of Covid in such situations. They instead think some mystery virus is causing both the positive test results and the symptoms. “Anything except Covid.” That mindset is not worth addressing.

Conclusion

Mask mandates pushed by the left were ineffective at reducing transmission of Covid-19, while the right misinterprets studies about the lack of effectiveness of mask mandates as indicating the lack of effectiveness of masks. They are not the same thing. Meanwhile, Covid tests are reliable, though false negatives are possible, and the PCR tests can produce effective false positives.