Covid-19: Asymptomatic Carriers

Why do so many people believe that they could be secret carriers of the coronavirus? Why, when I go on my daily walk, do my neighbors cross the street to avoid me, even though I have no symptoms, and have been virtually quarantined in my home for a month?  

Most of them are younger than me and I think they fear that they might infect me, an obvious senior citizen. Even though they have no symptoms, I believe that there is a widespread fear that many people are asymptomatic and infectious without knowing it.

Reading the newspapers or watching TV gives the impression that many people have in their minds the image of Typhoid Mary, the legendary woman who infected people with a dreaded disease even though she herself was not harmed. She was a secret carrier. 

However, it does not appear as if the coronavirus or any virus works that way. It is true that once infected, we may not show the familiar symptoms for a day or two, but then the symptoms: cough, fever, and fatigue must appear. Here is a timeline of the infection.

Typical Time Line of Viral Infection

Day 0 - you have been infected with a virus and have no symptoms but you are contagious.

Day 1-4  -  typical symptoms appear, fever up to 102 F, coughing, tired due to onset of the Immune response.  The Innate Immune system has already been initiated and the Adaptive Immune system is at work performing both the Humoral and Cell Mediated Responses.  You are most contagious now as you are coughing and sneezing out virus laden droplets.

Day 5-7 - you are feeling better fever still present but going down.  Less contagious but the recommendation is that you wait 24 hours after body temperature is back to normal before interacting with others.  

Day 7-10 - the virus has been neutralized but there are still many immune actions being taken by the body.   Different classes of antibodies are being produced with a maximum of these present at about 14 days after Day 0.  These will persist for months in the blood plasma.  The inflammation is being attended to so you may still be coughing up mucus.

Just today I saw a brief video from a Fairfield town health official who confirmed that we can only be asymptomatic for two days. We are not secret carriers of the disease for weeks, or months. When the virus enters our bodies, the immune system must immediately respond and cause symptoms of varying degrees to appear.  

The German study that caused Dr. Anthony Fauci back on January 31 to change his mind about the seriousness of the disease cited the case of a young woman from Shanghai, who after a visit from her parents in Wuhan, the apparent place of origination in China, flew to Germany for a conference. 

She had no symptoms but now we know that she infected some of the other participants in the conference. But shortly after, on the plane ride back home, she got sick. She was only asymptomatic at the outset. The lady from Shanghai eventually recovered.

This scenario was repeated in a story that recently appeared in my local newspaper that had the following alarming headline:

Yale doc: Asymptomatic Carriers spread half of virus cases.

A careful reading of the story indicated that the infected parties were only asymptomatic for a day or two. A man showed symptoms on Thursday, March 12. On Sunday, March 8 he had attended a large party in the town of Westport. a hot spot for the virus in Connecticut. The next day, March 9, he attended a basketball game in a crowded gym. He worked that week until the day his symptoms appeared on March 12.

It is most likely that he got infected at work especially considering that his nephew, who also worked at the same place, came down with the symptoms shortly after. The nephew worked until March 19 and showed symptoms on March 22. Neither uncle nor nephew were asymptomatic for more than a couple of days. Their symptoms were severe but did not require hospitalization, and they have both recovered.

Speaking of symptoms, so far in the USA more than 3 Million people have been tested for the coronavirus. At a recent news conference Dr. Birx of the CDC asserted that only 20% had tested positive for the coronavirus even though practically all of the tests had been done on people with symptoms. Only 24% of seniors between 65 and 85, the most vulnerable group, tested positive. 

The other 80% had some other reason for their symptoms, most likely the flu which so far this year has caused more deaths than the dreaded coronavirus. So far, of the 20% (about 600000) who did test positive only 26064 have died. 

About 96% of those who tested positive have not died, and the great majority have not required hospitalization. Most infected people just stay home and take to bed for a couple of days. For most of us the cure for the coronavirus is already in our bodies. Our immune system immediately attacks and destroys microscopic foreign invaders. Once infected a veritable war breaks out in our bodies that actually causes most of the symptoms like fatigue, cough, and fever.

Of course, we know that Senior citizens or those with high risk conditions like diabetes or immune system disorders are particularly vulnerable in the same way that they are to the flu. The immune reaction in their bodies is so strong that it causes inflammation and congestion that can result in deadly pneumonia. These vulnerable people are well advised to stay home.

At the beginning of the year the World Health Organization (WHO) decided to call the corona virus that originated in China in November of 2019 COVID-19. The acronym derived from the first two letters of each word plus the year of origination. Actually, a corona virus is similar to the virus that causes the common cold. Nevertheless, the ominous name made COVID-19 seem like an irresistible, unstoppable alien invader that could destroy the entire planet.

This virus like all others is no alien. It is as much a part of nature as we are. In fact, viruses existed before humans and may always have played a role in the existence of human life as we know it. COVID-19 is no different. When it enters or infects a human body, the immune system of most humans immediately attacks and ultimately destroys it. 

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Tracking the Coronavirus

                                                

I’ve been tracking the coronavirus statistics compiled by The Center for Systems Science and Engineering (CSSE) at Johns Hopkins University for the past three weeks. As of April 7 the CSSE has reported that there are 1359398 known cases worldwide resulting in 75945 deaths so far. 289109 of those cases have recovered although it would appear that recovery statistics lag behind. 

Worldwide, over the past three weeks the number of confirmed cases has grown by over a million, and the number of deaths has grown from about 6500 to 75000. But the rate of increase has declined dramatically in the past week. From March 23 to March 30 the number of reported cases jumped by 95% but in the last week the rate of increase was 65%. In the same two weeks the number of deaths continued to grow but at a slower pace. From March 23 to March 30 the number of deaths increased by 108% but in the past week the death rate increased by 88%.

It is difficult to draw conclusions from the worldwide numbers since not only do different countries have different reporting standards, but also some may even be suppressing information. It is hard to believe that the number of cases and deaths in China leveled off so rapidly a few weeks ago. 

However, the figures in the USA are also, despite alarmist headlines, somewhat hopeful. In the past three weeks the number of reported cases has grown from about 6500 to 368000, and the number of deaths has grown from about 500 to 10937. However, from March 18 to March 24 the number of confirmed cases increased by 615%, and deaths by 958%. From March 25 to March 31 confirmed cases increased by 198% and deaths by 304%. From April 1 to April 7 the number of cases increased by 94% and the death rate by 169%. While the numbers are obviously growing, the rate of increase is slowing.

Even though the number of deaths in the USA as of this morning is 14797, we hear predictions that the eventual number of deaths in the USA will be anywhere from 100000 to 1.2 million before the epidemic is over. What are these predictions based on?

A couple of weeks ago, an alarming banner headline in my local newspaper reported that there were 6800 people in Connecticut infected with the virus despite the fact that at the time there were only 68 tested positive in the state. A medical official with the State of Connecticut explained that although there was no way to estimate the effect of the coronavirus as yet, past experience with the flu would indicate that you must multiply by 100 the number of reported cases to get the true extent of the epidemic. In other words, 68 actual cases mean that at least 6800 people have been infected.

However, a couple of weeks later the same paper reported that two Yale researchers projected that the number of reported cases should only be multiplied by 3 to get an accurate estimate of the extent of the virus contagion. These researchers admitted that there were a number of variables and unknown factors that might cause them to revise their projections. 

The gap between these two estimates is huge and that is why we should be very careful when reading alarming headlines either in print or online. I prefer to look at what has actually happened and see what conclusions can be drawn from what we actually have experienced.

It is still too early to tell but it could be that the curve is flattening due to the widely practiced social distancing measures. Some also believe that as the days grow longer in the Spring the ultraviolet light of the Sun plays a significant role. It replenishes the Vitamin D in our bodies, an important element in a strong immune system. 

Also, it is important to note that as of April 8, 400000 cases of coronavirus have been reported in the USA. Of these cases, 12857 or 3.2% have died. Of these, the great majority of the fatalities were elderly with existing medical problems like hypertension and diabetes. But what about the remaining 96.8 percent? Recovery statistics lag behind for various reasons but even if we double the death rate, the great majority of those infected will survive, and even develop immunity. 

Finally, it is interesting to compare the statistics of the USA with other countries. Both the United Kingdom and Italy also show a flattening curve but as of April 8, there have been 55987 cases in the UK resulting in 6157 deaths, a death rate of 11%. In Italy, there have been 135586 cases (although some claim the Italians are not fully reporting) with 17127 deaths, a death rate of 12.65%. Even though the USA now has the largest number of reported cases in the world, the number of those cases resulting in death (3.2%) is significantly lower.

So far, these statistics seem to indicate that the USA health care system is doing a very good job of dealing with the crisis. Hopefully, when things calm down, studies will explain the disparities in the results. These studies might also help to put the whole pandemic into perspective.  The CDC has reported that last year in the USA there were anywhere between 35 Million to 50 Million cases of the flu, resulting in 500000 to 600000 hospitalizations, and 38000 deaths. 

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Coronavirus Immunity

In the past three weeks I have put up three posts on the coronavirus largely with the help and advice of my brother, Robert DeStefano, a retired high school master biology teacher with an intense interest in the workings of nature.  It would appear to me that the cure for the virus for most of us already already exists within our bodies. Please note the brief video at the end of the piece that actually shows killer cells hunting down unwelcome invaders.

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The staggering complexity of the human Immune system reveals a constant struggle against all sorts of infectious agents such as: bacteria, virus, fungus, and parasites.  I will break this essay into four parts:

A.  How do humans prevent infection from happening?

B.  Once infected what is the body’s first response (Innate Response)?

C.  How do humans rid themselves of the infectious agent (Adaptive Immune Response)?

D.  How does the immune system memory function?

A:      The skin, nose hairs (both visible and microscopic), mucus, tears, and cilia lining the respiratory tract all work to prevent infectious agents from entering the body.  Our skin is covered with harmless bacteria approximately 50 million to 5000 million per square inch.  The nose traps and surrounds infectious agents with mucus, chemicals in tears prevent infection, and the cilia beating upward in the respiratory tract cleanse the lungs.  A break in the skin, touching the nose, mouth or eyes with a hand which has touched virus, approximately 15, 000 of which could fit end to end on a pin head,  can overwhelm the body.  Inhaling virus infected droplets either coughed or sneezed out by an infected person could also overwhelm the body’s first line of defense.

B:       Now let us say a person has been infected which we experience more than we realize.  The immune system has two main types of White Blood Cells known as Neutrophils and Macrophages as part of what is called the Innate Immune response.  Neutrophils are thought to be primarily involved with bacterial infections but Neutrophils may also be involved with viral destruction as well; however, Neutrophil response can lead to collateral damage due to activation of an inflammatory response which can be life threatening.  Macrophages detect and engulf infected cells.  Infected cells usually display changes on their surface which Macrophages detect.  Some viruses have evolved a way to avoid having an infected cell display these surface changes, but in doing so lower the normal cell surface architecture which Macrophages can detect and thus destroy the infected cell.  They evolve; we evolve as we face a never ending battle. Destruction of these infected cells limits viral replication since a typical infected respiratory cell could release about 10, 000 new viruses.  Macrophages, once they have engulfed a virus infected cell, will then display viral antigens on their surface which will lead to another type of immune response call the Adaptive Immune Response.

C:      The body being infected must begin a twofold attack on the invaders.  With viruses, those virus particles roaming around the body in fluid such as blood or extracellular fluid must be destroyed. This is referred to as the humoral response.  Also, cells which have been infected with the virus must be destroyed before the virus can replicate and release more viruses into the body fluid in order to infect more cells.  This is referred to the cell mediated response.  Remember that Macrophages displayed on their surface virus antigens once they had engulfed and killed a virus infected cell.  This display of an antigen eventually promotes the production of B cells which start to produce specific antibodies which locate and mark the virus for destruction.  This antibody antigen reaction eventually results in the destruction of the virus.  The virus infected cells are also marked for destruction due to markers on the cell surface and these cells are destroyed thereby stopping further viral replication.  There can be consequences to the battle being waged in the body.  A variety of toxic chemicals can be produced such as histamine which can result in an inflammatory response which can lead to pneumonia.  Also, the levels of the killings cells must be brought back down to a pre-infection level or else these may actually start an attack on healthy cells of the body inducing an auto-immune response where the immune system is attacking what it is there to protect. Fortunately, there are suppressor cells which normally control the level of killer cells after the infection has been controlled.

D:      Once the invading agent has been destroyed, the antibodies which were produced remain in the body for months and therefore can quickly detect the same infectious agent and destroy it.  Also, a variety of long lasting memory cell remain active in the body constantly circulating looking for the same infectious agent. These memory cells can quickly respond to the same infectious agent and stimulate very rapid antibody production.   This is known as active acquired immunity which is what is produced by vaccination.  This usually provides for lifetime immunity to that SPECIFIC virus or bacteria.  Unfortunately, viruses such as the flu and common cold can mutate and require a new round of innate and adaptive immune response.  Scientists have long been looking for some similar aspect of all existing common cold viruses and flu viruses which could be targeted so as to be an effective vaccine for all cold and flu viruses.

Typical Time Line of Viral Infection

Day 0 - you have been infected with a virus and have no symptoms but you are contagious

Day 1-4  -  typical symptoms appear, fever up to 102 F, coughing, tired due to onset of the Immune response.  The Innate Immune system has already been initiated and the Adaptive Immune system is at work performing both the Humoral and Cell Mediated Responses.  You are most contagious now as you are coughing and sneezing out virus laden droplets.

Day 5-7 - you are feeling better fever still present but going down.  Less contagious but the recommendation is that you wait 24 hours after body temperature is back to normal before interacting with others.  

Day 7-10 - the virus has been neutralized but there are still many immune actions being taken by the body.   Different classes of antibodies are being produced with a maximum of these present at about 14 days after Day 0.  These will persist for months in the blood plasma.  The inflammation is being attended to so you may still be coughing up mucus.

Try to think of the face as the deadly Bermuda Triangle.  Imagine a triangle extending from above the eyes down to the chin.  These are areas to be avoided especially the nose through which most viruses gain entry into the body!  

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Note: Here's a follow up from my brother:

The CDC reported for the 2018-2019 flu season of which they have real data over a period of time from Oct to March, that somewhere between 35 million to 50 million cases of the flu in the US! 500,000 to 600,000 hospitalizations and probably 35,000 deaths with 92% of deaths involving people with diabetes. How come this level of infection doesn't seem to overwhelm the medical profession?

Coronavirus Statistics

                                              

Doris Burke, Virus survivor

I’ve been tracking the coronavirus statistics compiled by The Center for Systems Science and Engineering (CSSE) at Johns Hopkins University for the past two weeks. As of March 29 the CSSE has reported that there are about 678720 known cases worldwide resulting in 31700 deaths so far. About 145000 of those cases have recovered although it would appear that recovery statistics lag behind.

For the past two weeks the number of reported cases has grown between 12 and 13 percent per day. Obviously, as more testing is done the number of cases will continue to increase. A couple of weeks ago, an alarming banner headline in my local newspaper reported that there were 6800 people in Connecticut infected with the virus despite the fact that at the time there were only 68 tested positive in the state.

A medical official with the State of Connecticut explained that although there was no way to estimate the effect of the coronavirus as yet, past experience with the flu would indicate that you must multiply by 100 the number of reported cases to get the true extent of the epidemic. In other words, 68 actual cases mean that at least 6800 people have been infected.

If we use this estimate, it would mean that over 67 Million people worldwide (678000 actual cases multiplied by 100) have already been infected with the virus. That translates into a death rate of .0004, much less than the death rate per actual cases. In other words, out of 1 Million people infected, approximately 470 will die from the corona virus, and most will be elderly with existing respiratory problems. Even if you drop the estimate in half and say that the actual reported cases should be multiplied by 50 rather than 100, the death rate would still be miniscule, and no more serious than it was in other flu seasons.

Worldwide, approximately 4% to 5% of reported cases have resulted in death. In the USA so far, approximately 124600 cases have resulted in 2300 deaths, about 1.8% of the total. The USA death rate compares very favorably with countries like Italy with a death rate of over 10% and the United Kingdom were the death rate is almost 6%. 

A columnist in yesterday's Wall Street Journal referred to two studies with differing approaches to the epidemic. The first called for a continuation of the current measures that amount to an almost complete shutdown of the economy. The other study proposed less draconian measures: seven-day isolation of those with symptoms, 14-day isolation of exposed households, and “dramatically reduced social contact for all those over 70 years of age.” 

My wife and I are both age 80 and although healthy, we have been in virtual quarantine for the past three weeks. I can understand the need since the great majority of people who have died have been elderly.  However, given the statistics cited above I believe that it is time for young people to go back to work, and for children to return to school. 

In today’s newspaper there was a story about a sportscaster for ESPN who was very sick for a couple of days, and decided to get tested. It took eight days to get the test results but sure enough, she tested positive for the coronavirus. Like most healthy people she quickly recovered and is probably able to get back to work. Moreover, it is very likely that she and the other millions who get infected by the virus will be immune from future attacks.

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