Thinking Critically About COVID-19

Coronavirus, COVID19, or SARS-CoV-2 are all names that you've heard for the novel virus that was first identified in Wuhan China in 2019 and that's currently severely disrupting our way of life throughout the world. This is the same virus that has overwhelmed the healthcare systems of various countries, has been called a “hoax” by certain world leaders, has led to social-distancing practices implemented throughout the world, and forced us to redefine our new normal. All this havoc has been caused by an organism that is typically measured in nanometers (i.e., .000000001 meters or .0000008 inches) and is best described as “organisms at the edge of life” given their unique characteristics which doesn't quite allow them to be considered “life” as we normally define it.

Along with all of this disruption has come quite a bit of misinformation. In today's article, we're going to look at what I believe are the top 3 myths and detail why they're wrong. Further, we'll take a look at a few other salient topics that are important for you to understand. You don't want bad information to come between you and your health during these challenging times.

Terminology

As you’ve probably already noticed, depending on the source, the name assigned to this virus appears to vacillate between “Coronavirus,” “COVID-19,” or “SARS-CoV-2.” While all of these names are not wrong to use for the virus, there are nuances here that must be addressed to better understand where these names come from. First, the name “Coronavirus” is referring to the fact that this virus is a part of a group of viruses, which are known as “Coronaviruses” that can cause disease in animals and humans. These viruses often circulate among cats, camels, and bats, and can sometimes evolve and infect people as well. Coronaviruses get their name from the crown-like spikes on their surface [1].

Last, as is often the case with viruses that lead to infectious disease, there is a specific name that it’s given as well as the disease that it causes. In this instance, COVID-19 (i.e., “coronavirus disease”) is the name given to the disease, which is caused by SARS-CoV-2 (i.e., “severe acute respiratory syndrome coronavirus 2”); the name for the virus. Again, while all of these names are not wrong to use interchangeably when speaking about the virus colloquially, it is important that you understand the nuance between the group name that the virus belongs to, the name for the specific virus, and the name for the disease that it causes [2].

Myths

1: The Virus was Engineered

This was one of the first aspects of this virus that scientists wanted to better understand when it was first discovered. Thus, scientists did what they do best when confronted with an unknown, they crafted a detailed experiment in order to answer the question of the virus's origin. This study was published recently in Nature Medicine - a very prestigious journal - and stated the following [3]:

“SARS-CoV-2 is the seventh coronavirus known to infect humans; SARS-CoV, MERS-CoV and SARS-CoV-2 can cause severe disease, whereas HKU1, NL63, OC43 and 229E are associated with mild symptoms6. Here we review what can be deduced about the origin of SARS-CoV-2 from comparative analysis of genomic data. We offer a perspective on the notable features of the SARS-CoV-2 genome and discuss scenarios by which they could have arisen. Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.”

As of right now, the evidence points to this virus being of natural origins.

Another closely related conspiracy theory that I've come across a number of individuals touting is that this virus was engineered or released to hurt President Trump's chances of being re-elected. The evidence presented here debunks the “engineered” argument, but an argument could still be made that this virus was captured from the wild and then strategically released. However, the chances of a novel zoonotic disease being discovered without the scientific community knowing about it would require the orchestration and suppression of hundreds of people if not thousands, which, in my estimation, would have a probability for success somewhere in the vicinity of vanishingly close to zero. I suppose that it could happen, but, given the evidence available, seems incredibly unlikely.

2: This is Just Like the Flu

It is true that there is a degree of overlap between the two when it comes to disease presentation (i.e., symptoms). For example, they both cause respiratory disease, which can present itself in a range from being completely asymptomatic to severe and death. Furthermore, both viruses are transmitted through contact, droplets and fomites. Due to this, similar public health measures, such as hand washing are important actions when it comes to preventing infection.

However, this is where the similarities end. One of the primary differences between the two viruses is what is known as the reproduction number. That is, the number of secondary infections generated from one infected individual. For influenza, the reproductive number is between 2 to 3, while for SARS-CoV-2 it is between 1.5 to 3.5 [4]. As more information comes out, the range for the SARS-CoV-2 reproduction number will be further refined, but, at the moment, the evidence supports the reproductive number for SARS-CoV-2 virus being greater than that for influenza.

Another important difference is the fraction of those infected with severe disease. For COVID-19, the data points to 80% of infections being mild or asymptomatic, 15% are severe enough to require oxygen, and 5% are critical to the point of requiring ventilation. Compared to influenza, the fraction of severe to critical infection is greater for COVID-19.

For influenza, those most at risk for severe infection are pregnant women, the elderly, children, immunocompromised individuals, and those with underlying chronic medical conditions. For COVID-19, the most at risk is narrowed to those of older age and underlying conditions.

Last, the infection mortality rate from COVID-19 appears to be higher* than that of influenza which is usually below 0.1% [5]. That being said, there are generally a few different values that are being communicated through various media channels and it's important to understand the distinctions between these different metrics. For example, there are generally three different metrics that are discussed. They are the “Case Fatality Rate” (CFR), the “Crude Mortality Rate” (CMR), and the “Infection Fatality Rate” (IFR).

The CFR is simply the number of people who have died from the disease and divide it by the total number of people who have been diagnosed with the disease. For example, if you had a total of 100 people diagnosed with the disease and 10 of them died, the CFR for that particular disease is 10/100 = 0.1, or 10% of those who contract the disease end up dying from it. Mathematically,

The CMR measures the probability that any individual in the population will die from the disease. It's calculated by dividing the number of deaths from the disease by the total population. For example, if there were 10 deaths in a population of 1,000, the CMR would be 10/1000 = 0.01, or 1%. Mathematically,

However, it's important to keep in mind that this factor is 1% even if the total number of people diagnosed with the disease was 100. It is important that you understand this distinction as the CMR is sometimes conflated with the CFR and, clearly, the CFR is a more useful metric than the CMR when attempting to compare the mortality rate of various diseases.

*The IFR is the most useful metric of the three when juxtaposing diseases to compare mortality rate. It is described as the number of deaths from the disease divided by the total number of cases. For example, if 40 people die from a disease when 1000 people have it, then the IFR is 40/1000 = 0.4, or 4%. Mathematically,

Thus, there are two numbers required in order to calculate this value, the total number of deaths and the total number of cases from the disease. However, unlike the number of diagnosed cases as is required for the CFR, the total number of cases for COVID-19 is unknown, which is partly due to the lack of testing. That is, there are individuals walking around with COVID-19 who are asymptomatic and will have never known that they contracted the disease. As a result, they are are not being counted, which is going to cause the CFR to be higher than it actually is. I reference the CFR here because this is the number that is often reported and not the IFR [6].

Now, just because the total number of cases is not known doesn't mean that accurate estimates can't be made. Scientists use the best tools available to them in order to make this estimate, but it's important to admit that it does have limitations and that the calculated IFR isn't 100% accurate. That being said, it is still a useful metric when comparing the mortality rates of various diseases.

3: There's Nothing that Can be Done Without a Vaccine

While a vaccine is the best option available when it comes to infectious disease, realistically, a vaccine is 12 to 18 months away. In the meantime, the public needs to strictly adhere to recommended health measures in order to suppress the spread of the disease. These measures include hand washing, good respiratory etiquette (i.e., coughing into a tissue and/or elbow and immediately disposing of the tissue and/or thoroughly washing the area), decontaminating surfaces, and social distancing, which includes potentially having to isolate those most at risk for severe infection.

Beyond a vaccine, there is continuing research into other medications that can help to treat the symptoms as well as medications that will soothe the body's inflammatory response to the infection. Having effective medications that can help to calm the immune system is advantageous as the body's inflammatory response can be severely disrupted by this disease and lead to what's known as a “cytokine storm”, which can be fatal [7]. The overarching goal of this particular class of medications is to increase survivability once the disease has already been contracted.

Note, President Trump has lauded two malaria drugs - chloroquine and its safer derivative hydroxychloroquine - as treatment for COVID-19 [8]. Bluntly, this is incredibly reckless behavior coming from a world leader as it’s based off of a small amount of evidence and not recommended by the scientific community. In a March 23 editorial, H. Holden Thorp, the editor-in-chief of the prestigious journal Science, cautioned against excessively hyping therapies that remain speculative [9]:

“Political overhyping of such approaches is extremely dangerous — it risks creating false expectations and depleting drugs needed to treat diseases for which they are approved,” he said. “And it sets science up to overpromise and underdeliver.”

I concur. Until more studies have been done, it’s best to focus our efforts on producing more of what we know does increase survivability, such as ventilators. That said, the scientific community should absolutely move forward with more testing, but it shouldn’t be recommended to the general populace until more powerful studies are done (i.e., studies that are higher up on the hierarchy of scientific evidence).

Now that we've discussed some of the more salient myths surrounding COVID-19, let's discuss a couple other important topics that deserve attention.

Exponential Growth

One of the most important mathematical concepts that needs to be understood when discussing how this disease progresses is the exponential function. This function takes the following form:

Where f(x) is the symbol for “function,” a is any constant number (e.g, 2,3, etc.), and x is also going to be a number, but a number that is allowed to vary (i.e., it doesn't stay constant). For example, if a = 2 and we were to graph this function by allowing x to vary, we would arrive at the following graph:

As you can see, the graph is small and then suddenly undergoes a meteoric rise once reaching a certain point, which is sometimes referred to as the “knee in the curve” [10]. Now, let’s compare exponential growth to linear as well as cubic growth:

where the red graph is linear growth, the blue is cubic growth, and the green is exponential growth. Once again, the exponential graph is small early-on, but then quickly dominates the other two as it undergoes its meteoric rise.

Taking this function and applying it to the real world, we often see this type of behavior in simple dynamic systems (i.e., a model describing the temporal evolution of a system) such as bacterial growth. What is more, this type of growth just so happens to accurately model infectious disease transmission for certain diseases. In particular, COVID-19 infection follows an exponential trajectory as can be seen in the following graph from John Hopkin's interactive dashboard on reported cases [11]:

Once more, you see a very slow rise initially until meteoric growth takes over.

It can be difficult to understand just how quickly exponential growth advances once the numbers become sufficiently large. Graphs help to some degree, but there is an old riddle about a lily pad in a pond that helps to further visualize the rapid growth and, what is more, the seemingly insignificant growth that occurs in the beginning.

There is a singly lily pad in a pond that doubles every day and covers the entire pond in 30 days. On what day does the lily pad cover half the pond?

If you answered “15” without putting much thought into it, you’re wrong. Don’t feel too bad though because our minds are wired for linear thinking and this is the answer that most immediately go to. If you answered 29, then you are correct. If the lily pads cover the entire pond in 30 days where they double every day, then half of the pond would be covered the day before the entire pond was covered, which is day 29.

A more interesting question is, how much of the pond would the lily pads cover on day 15? The answer, which highlights how slow exponential growth is in the beginning, is just .0031% of the pond. Calculating further, the lily pads will actually only begin to cover over 1% of the pond on day 24. As can be seen from the numbers, exponential growth can be difficult to understand as the changes are so insignificant in the beginning until you’re suddenly overwhelmed by huge numbers.

At this point, it's important to note that this type of growth won't last forever. Eventually, as more people contract the illness and either die or develop immunity to it, the number of new cases will eventually plateau and hopefully begin to decline. This has often been observed in other areas of science, such as the modeling of population growth, and is known as “Logistic growth.” Thus, technically, “Exponential growth” is really nothing more than a certain phase or time period within a logistic growth model as exponential growth cannot continue forever within a closed system; it defies the laws of physics. That said, exponential growth within biology is in actuality a phase within a logistic growth model:

Note, the dashed red line indicates the point at which growth reaches equilibrium (i.e., the population, the number of new cases, etc. doesn’t change or oscillates around an average value) and is either maintained moving forward in time or begins to decline until reaching another equilibrium position [12].

Flatten the Curve

What does “flattening the curve” mean? Put simply, it means that we want to distribute the number of cases out over a longer time period so as not to overwhelm the healthcare system. Why? If the healthcare system becomes overwhelmed, then the people who need access to it won't be able to because it's already at capacity. This not only means that people with COVID-19 won't be able to get the help they need, but it also means that people who have heart attacks, strokes, accidents, etc. won't be able to get the care that they need either. If this were to happen, then Doctors would be forced to triage between which patients live and which die. This is an awful situation to put anyone in; especially if it's avoidable. By flattening the curve, lives are saved; it’s that simple [6].

Who Should you Listen to?

In challenging times such as this, knowing who to listen to for good information is more important than ever. As has been discussed in other articles such as “How to Identify and Combat Weaponized Disinformation in the Digital Era,” we live in a world of abundant information, but with the good also comes the bad, so you must learn how to sift through all of this information to distill the facts from fiction. You must know how to identify credible sources for information.

One of the best sources of information during a crisis such as this, is going to be the scientific community. They are the experts when it comes to infectious diseases, so they are going to be the people that you want to listen to. Below are a list of credible resources that I highly recommend you follow:

This is an up-to-date database about cases per country: https://www.worldometers.info/coronavirus/
Our World in Data has done a fantastic job of compiling statistics from all over the world and organizing them into easy-to-understand charts and graphics: https://ourworldindata.org/coronavirus#citation
This is John Hopkin’s interactive dashboard that was mentioned above. It displays visually the total number of cases on a global scale. Further, it allows you to click on individual countries to explore their metrics and it displays other metrics such as “Total Deaths” and “Total Recovered” as well: https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6
The WHO is the best source to get your news from as they are the leading authority tasked with handling the pandemic: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/media-resources/news

Concerning credible sources of information outside of the scientific community, your Government leadership should be communicating to you the best information available. Unfortunately, egos and politics can get in the way and these officials can be lead to bend the truth. Now, this certainly isn’t the case with all Government leadership, but given that it can be difficult to parse the good from the bad and even discern which official to listen to in the first place, it’s best to listen directly to the scientific community.

Conclusion

The ongoing pandemic is not going to end overnight and it will be at least a year until our greatest weapon - a vaccine - is even available, but that doesn’t mean that we’re helpless. Hand-washing, social distancing, and other measures can be implemented in the meantime to slow the rate of infection and increase survivability. It is important that all of us adhere to the recommended guidelines for social distancing and hygiene so that we can “flatten that curve” and give our healthcare system the help it needs to properly navigate this pandemic without becoming overwhelmed. It could be your brother, or sister, a parent, or grandparent, perhaps a close friend who becomes ill and needs emergency medicine in order to survive. This is why we do it.

As a Critical Thinker, please make an effort to correct misinformation or even censure conspiracy theories when you encounter them. This disinformation can cause individuals to not take this crisis seriously and fail to properly partake in recommended mitigation strategies. The only way the mitigation strategies do their job is if we all partake together. Quite literally, conspiracy theories and other forms of disinformation could potentially cost lives if we don’t push back against them. Together, we can push back against this assault of disinformation and hopefully reduce unnecessary deaths. Sadly, we will lose a number of individuals to this disease, but together, we can make sure that when we look back, we can say that “we did our best.”