With symptoms ranging from a gasping death to nothing at all, one has to wonder whether COVID-19 is a super flu or a mild cold. Have we ruined our economy over nothing or saved millions of people from death? If COVID-19 is a mild cold, how did we mistake it for a super flu?
There are over 200 different viruses that cause the common cold. The most common are rhinoviruses, coronaviruses, adenoviruses, and respiratory syncytial viruses. The average person gets one to three colds per year, and due to the large variety of viruses responsible, there is no vaccine. Influenza is another common respiratory virus. Cold or flu, respiratory viruses present similar symptoms and follow the same life cycle. Launched into the environment from their current host, they might survive long enough to find another. Typically by inhalation, they might make their way to the mucosa. They might make it past the wall of mucus to the underlying cells, where they might manage to infect one. Irritated by the intruder, the cells send an alarm and macrophages soon begin the equivalent of carpet bombing. The release of cytotoxic chemicals causes tissue damage and even more irritation. The mucosa releases more mucus, filling the sinuses and dripping into the lungs. Cilia move mucus out of the lungs up to the throat, where most of it makes its way to the stomach, but coughing is also an option, launching virus into the environment.
The more specialized 'T' and 'B' lymphocytes make their way to the infection where they test the infectious agent to determine if they are a good match. Once a 'B' cell matches close enough, the precision strikes start. The adaptive immune system further alters its genetics to make an even better match. For example, the common coronaviruses, HCoV-229E, OC43, NL63 and HKU1 look a lot like the SARS coronaviruses and prior infection with one provides partial immunity to the others (acquired immunity).
This is the important part: the bulk of the damage and symptoms are caused by the immune response, not the virus. This is why all of those vastly different respiratory viruses have similar symptoms, and even airborne irritants cause cold-like symptoms (e.g. allergies). It is highly unlikely that any respiratory virus will ever be a super flu, because the severity of the illness is limited to the body's ability to damage itself. Not that the body lacks such an ability. Consider what might happen if multiple irritants were present simultaneously, such as chronic emphysema (from pollution or dust), allergies or diabetes (sugar is inflammatory).
Why is SARS so bad? When the virus infects the upper respiratory tract we get a stuffy nose. When the virus infects the lower respiratory tract we get stuffy lungs. SARS-like coronaviruses typically infect the upper tract but can get down into the lungs, more than typical for cold viruses. SARS-like coronaviruses are cold viruses, ones with increased potential for a very bad, but not uncommon outcome.
We measure the danger of communicable diseases by the proportion of infected people that die and how well they spread. Flu is the standard, killing about 0.1% of the infected with about a 30% chance of spreading to same-household family members. COVID-19 looks to kill about 1.5% of infected people and has about a 55% chance of infecting a family member.
Deadly and virulent, so why suspect that this might be a mild cold?
There is a problem with the denominator. We only test those who report to doctors, but colds are so common and symptoms can be so mild that only 1-in-5 to 1-in-10 infected people go to the doctor. The mortality rate from COVID-19 might be closer to 0.15%, more in line with influenza.
There might be many more cases, to a level that COVID-19 already ripped through the United States. Although it was widely reported that this outbreak began on December 31st, the World Health Organization's charts show COVID-19 deaths declining by January 10, and the first confirmed cases appearing around December 2nd. Cases outside of Wuhan grew in parallel with Wuhan, rather than delayed, suggesting that COVID-19 was already widespread in China by mid-December, a good trick for a country with state-limited mobility. If only 1-in-5 people ended up in the hospital, this could have begun in late-to-mid November. The Diamond Princess was infected by a guest who boarded on January 20th and Milan was infected by visitors on January 23rd, so this had already spread through China enough that they were spreading it to the world. There have been a few reports that the Chinese were noticing something happening in October.
If the start date was a month or more before December 31st, then we are not talking about 7,000 cases in the U.S. starting in early February, but 6,000,000 to 10,000,000 cases starting in late December. This means that rather than a 0.15% mortality, COVID-19 is nearly harmless. If fewer than 1-in-5 people are reporting to their doctor, the start of COVID-19 is pushed back even further, enlarging the number of infected to point that COVID-19 is this year's common cold, and most people have already had it.
How could we miss harmless? COVID-19 was so bad in Wuhan that the Chinese and WHO concluded it was SARS. The possibility of pollution-induced chronic emphysema or the incompetence of socialized medicine complicating a cold into a super flu was never considered. China, and then the rest of the world, focused on those who were wheezing for breath, even going so far as to decline testing people (in the vicinity of the infected) just because they were breathing normally, sending them on their merry way to infect others. We focused on the extremely ill, everyone did, turning to China and the WHO for guidance. Oops?
We put fearmongers in charge. Dr. Anthony Fauci is the head of the National Institute of Allergy and Infectious Diseases (NIAID). As the head of NIAID, one of Fauci's core responsibilities is to get Congress to spend more money on infectious disease research. For decades, he has testified that the cure for AIDS is right around the corner, that ebola virus is coming for us, or that some cross-species plague will emerge from a Chinese wet market, and we just need more money to research it. The current events have played right into his fantasy, but as pointed out above, it is a fantasy. This is the equivalent of noticing holes in the ozone layer and then putting Chicken Little, an expert on the sky, in charge of the response.
We eventually realized that the holes were always there, and we will eventually realize the true magnitude of COVID-19, years from now, hidden in the scientific literature. But there are already hints. China reported a declinewithin a week of starting its "social distancing" in early February, but the decline was already apparent in late January. The U.S. is seeing a booming increase after its social distancing, as medical professionals are starting to test more people with sniffles and no history of contact with the known infected. Could it be that the disease was already burning out in China, and we are taking our focus off the worst cases in the U.S.? COVID-19 is shaping up to be a mild cold, and potentially a very mild one at that.
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