- Virus– a type of germ that consists solely of a bit of genetic material (DNA or RNA) wrapped in a protein coat. The coat gets the genes into the target cell where the genes force the cell to make zillions of new viruses, and on it goes.
- Coronavirus– a species name of a number of different viruses. Called corona because its protein coat is studded with spike shapes that form a crown, halo, or corona of spikes
- SARS-CoV-2– the specific name of the new coronavirus
- COVID-19-the name of the illness that the new coronavirus is causing
- Endemic– an illness always present in a region. One could say strep throat is endemic in the US
- Epidemic– a sudden burst of an illness that comes and goes over a limited time
- Pandemic– an epidemic that bursts across the world not just one region
- Spreadability– how contagious is the disease, how many people will end up infected
- Symptoms- the experience of being ill, for example- fever, cough, headaches, loss of smell etc.
- Asymptomatic– literally means “without symptoms”. For COVID-19 it refers a person infected with the virus but has no and will have not symptoms
- Presymptomatic– This is a person who was infected with SARS-CoV-2, and will feel sick, but hasn’t yet
- Severity– what harm does the disease cause, in terms of how sick you get and how many it will kill
- Mask- a mask is a loose-fitting cloth or textile that covers the mouth and nose loosely. A surgical mask is a mask used in surgery
- Respirator- for the purposes of the COVID-19 pandemic and other respiratory illnesses, a respirator is a mask that fits very snugly or tightly to the user’s face. An N95 mask is a respirator.
- Personal Protective Equipment (PPE)- PPE are any item that covers any part of the body with the design and intent of keeping viruses in the environment from infecting the wearer of the PPE. PPE’s include all masks (which includes respirators), face shields, eye shields, gloves, gowns.
- Ventilator- a ventilator is a machine that can force a person unable to breathe to inhale and exhale and control both effectively. They are sometimes called respirators, but during this pandemic the word respirator is now reserved for reference to a tightly fit mask.
- Live Virus Swab– this is the swab which attempts to swipe live virus from one’s nose or throat to see if you are currently infected.
- Antibody Test- (aka serology test) this is the blood test which looks for antibody to the SARS-CoV-2 virus to see if you have been infected in the past.
BIOLOGY OF THE SARS-CoV-2 VIRUS
We tend to think of viruses as somehow unreal. So tiny they are almost just a bunch of atoms, never to be actually seen. But they do have visible structures, it just takes a very powerful microscope to magnify them to be visible.
But someone has done just that, and this story from The New York Times allows us to see the new coronavirus. https://www.nytimes.com/interactive/2020/health/coronavirus-unveiled.html?referringSource=articleShare
These images are not for the faint hearted. The virus is seen in all its powerful glory with the now very familiar spikes forming a crown, or corona, on its spherical surface.
Later in the article is the most impressive photo, in my opinion. It shows how the spike proteins attach to a cell. Many of us know that there is a particular protein on the surface of many of our human cells that this virus needs to find to attach to, and once attached, to enter our cell. Some of us have heard that protein on our cells is called the ACE2 receptor. This is a process common to all viruses. They need to gain entry to the cell, or they cannot ever infect. And all viruses gain entry to all cells via a specific protein that juts out of their target cell. Once attached, the virus becomes like a key in a lock, opening the door, entering the cell, and launching its infection.
Now for the first time, we can see the virus docked, attached, linked, to the tiny little protein molecule sitting on the surface of our cell. The virus looks like the planet Jupiter with a teeny, tiny little thread curling around a tiny little thread on the surface of our cell, painted in this photo the color yellow.
To think of all the agonies unleashed by disease, economic collapse, political incompetence by these two tiny threads connecting makes this photo so staggering.
K- The Name of the Dispersion Parameter: It Impacts How we Stop the Virus Spreading
Take a person with any virus and put them in a room of 100 people, how many people will that person infect? That is a measure of how contagious the virus is.
But viruses are a tricky thing. Some spread to the same number of people in that situation, every time. Measles is that way. Put someone with measles in a room with 100 people who have not had it or not been immunized, and 90 people will leave that room with measles every time.
Not all viruses are that steady. Take SARS-CoV-2 for example. It is estimated that about 80% of the infections come from only 10% of those infected. In the United States, we know of about 7 million people with COVID-19. We think about 5 1/2 million of them got infected by only 700,000 of the 7 million walking around with the infection!
Now comes a terrific article on this property of viruses, the variability of its catchiness, which technically is called its rate of dispersion, and the number assigned to that is the k parameter.
Here is the article: https://www.theatlantic.com/health/archive/2020/09/k-overlooked-variable-driving-pandemic/616548/
The article does a great job of discussing the meaning of this property called dispersion, this number called k. A k value of 1.0 says that the chance that someone will spread a virus is about the same in every situation. But a k value less than one says that some people in some situations will spread it better than in other situations.
Here are some highlights:
- The influenza virus is more like measles than the SARS-CoV-2 virus, it will spread to about the same number of people in similar settings. Such viruses cause very predictable outbreaks. Someone infected enters a room with uninfected and outbreaks occur at the same level nearly every time. It has a k value of about 1.0
- The SARS-CoV-2 virus is not so even, far from it. Person A, contagious with COVID-19, could go to a family get together and infect no one. OR person B, also contagious with COVID-19, could go to a family get together and infect 40 people who then go on to infect 80, then 160, and spark a huge outbreak. The k value for all the new coronaviruses is about 0.1 to 0.2.
- Those other coronavirus illnesses include the original SARS disease in East Asia, Toronto, and other areas in 2003 or so, that was halted from spreading back then entirely. And the MERS which is not very contagious and limited to areas of the Middle East. The third new coronavirus infection, our COVID-19, also has a low k value, about 0.1 or 0.2. This explains why about 80% of the infections have been started by only about 10% of those infected.
- This pattern of uneven infection means that to stop the virus from spreading, one must find those few occasions when big spreads occur. If person A has COVID-19 and we know they will not infect anyone, isolating person A will offer little benefit to limiting the spread. But if person B has COVID-19, and we know they will be in a situation that causes a big burst of infection, that is the sort of event we need to know about and isolate all involved to prevent an explosion of disease.
- The event of that one person, in just the right setting, infecting many many people, which fuels this pandemic, is the now familiar super-spreader event.
- The science of uneven spreads, or spreads of infection in bursts, tells us that our best bet is to pursue three strategies that few nations have mastered.
- The first is called looking backwards. Our current approach looks forward. Let’s say a teacher tests positive. Our response is to test everyone he has been in contact with. That is looking forward, because we are asking, who will catch this from him next, in the future? Looking backward asks a different question. In this example, looking backward would involve asking where the teacher caught the infection, some time in the past? Looking backward allows us to find more super spreader events. Because so few infected people cause so much of our COVID-19 cases, looking backward often can reveal a super-spreader event, which then allows investigators to test everyone exposed to an event that really does generate most of our infections.
- The second is finding clusters, not people. If 80% of all the viral spread of COVID-19 comes from super-spreader events, finding ways to detect these events, then isolating all those present, is better than testing one person at a time. This is an argument for using relatively inexpensive tests that are cheap and rapid, like the rapid saliva test, which may tell an infected person they do not have the infection (a false negative), but could find clusters of infected people because the test can be done very quickly to large numbers of people over and over again. Say a group of 100 people infects 20 in the group, and the cheap test is done over and over, and finds 10 of those 20 infected. Then a cluster, or super-spreader, event can be detected. That group can be instructed to have all 100 people isolated to stop the event and prevent thousands of getting sick.
- Avoid settings where the vast majority of super-spreader events. The research on the k value of COVID-19 has revealed, along with other studies, that there are certain situations where most super-spreader events take place, not all risks are created equal. So, avoid these situations and super-spreader events will become far less frequent, and the spread of this virus can be slowed. Those key situations are:
- Closed spaces- Indoors
- Close contact (the three C’s)
- Poor ventilation
- Loud talking, singing or shouting
- The other variable harder to control is having a person with a very high amount of virus in their breath present when these 4 elements are happening.
The entire concept has proven its value in Japan where they employed the above 3 strategies, backward looking for source events, finding clusters, and preventing the three C’s (see just above). It has worked, without lockdowns.
The current trends in our United States are both not good, and predictable. The spread of COVID-19 is currently on the rise.
Over the course of the pandemic, one trend has been seen in every part of the world, over, and over, and over, and over again: As long as the virus is present, when people gather the virus spreads. Period.
Now, if a community allows some gathering and at the same time is able to detect the first appearance of that inevitable spread, then the neighborhood, city, state, or nation can avoid a deadly spike of the disease.
If a community allows a lot of gathering and ignores trying to find those early spreads, then nationwide surges will happen, every time.
A look at our nation since the appearance of the COVID-19 pandemic in late January tragically demonstrates the undeniable and unavoidable truth of these patterns of spread.
Throughout this year, for reasons that every month become more difficult to understand and accept, our nation has decided not to try to detect small outbreaks after people gather, and as the above makes clear, the result is predictable.
A brief look at the year tells us much of what we need to know about where we stand today.
The first spread after being together
This took place after the virus first arrived unleashing a horrible wave of illness and death, forcing the nation to take a very deep break. That was the time of sheltering-in-place of April and May. We brought our nation’s daily case count down from 32,000 new cases a day down to 22,000 a day. It was working.
The second spread after being together
The first get together after the great shelter-in-place took place starting around Memorial Day. You may remember the stress of 2 months of being at home was followed by the almost urgent relief of gathering together again. We did so across much of the nation with abandon, with bars and restaurants opening particularly in the South. We were more gradual in getting back together in Ohio. And New York, after suffering much of the devastation of the disease in the first spread, opened up most carefully, and crucially, took very real steps to watch for early outbreaks when they were very small.
The nation saw its daily case count explode from 22,000 a day up to 78,000 cases a day (July 20), the highest count of the pandemic to date. This happened largely by broad national outbreaks with peaks in Florida, Georgia, Arizona, Texas, and Southern California, where as noted, people re-gathered rapidly and with few restraints, and where there were effectively no real efforts made to catch the early signs of new outbreaks, and snuffing them out before they became huge.
Ohio regathered cautiously, and our increase in cases was modest.
With careful regathering and careful monitoring, New York had no surge over the summer.
Early signs point to us entering a third spread after being together
As with the first deadly spread of COVID-19, the second forced states to reduce getting together, and once again it worked, bringing our daily counts down from that deadly peak of 78,000 to 32,000 once again by September 6.
This time America would relax its vigilance by opening bars and restaurants, but also by going back to college. The iron rule of all respiratory viruses (colds, flus, and COVID-19) once again was observed, if you gather, you spread.
And so now across the US, the pandemic begins to spread a third time. Starting on college campuses the spread extended into communities across the nation. But at the same time, the nation began to regather with more weddings, funerals and family get-togethers. And still, after all we have learned, no special effort at trying to catch early signs of outbreaks outside of New York.
Regathering, colleges, family events, bars and restaurants, and now perhaps even schools combine with the coming of winter to put us all in grave danger.
As of this this weekend, the United States has reached a daily case count of 57,000 with over half our states seeing very significant surges. According to Dr. Osterholm today, our nation is facing the worst outbreak yet.
And here at home, just this weekend, our office has noticed a significant rise in the number of outbreaks across our communities. We are impressed with the number of cases erupting in a variety of team sports, for example soccer and hockey. We are impressed that cases are starting to crop up in schools and pre-schools.
The first two vast outbreaks killed over 200,000 of us, this next one threatens to do the same. Now is a time calling for great care.
Lessons from around the world
We are not the only part of the world demonstrating that gathering causes increased spread, which can only be stopped with careful identification of the infected and their isolation while infected.
In Europe, surges of infection are being seen in a number of countries, including the UK, France, Spain, and the Netherlands. This is clearly the result of too rapid relaxation and regathering, but since they brought their counts so much lower than in the US when they stopped the spread, the current European surge is far smaller than ours.
And in East Asia, the decision to put resources into truly monitoring small spreads of infection, identify the infected and stop the spreads at their start, has been shown to be spectacularly effective. Taiwan a nation of nearly 24 million people through today, has suffered a total of 7 deaths! This strategy works. Had the US, a nation of 320 million people simply followed the same care that Taiwan did, we would have a total of about 100 deaths, not 215,000.
- This post starts with a link to an article featuring astounding microscopic photos of the SARS-CoV-2 virus.
- Implications following the curious path this virus actually takes to infect us are discussed in detail. That curious path is in bursts, not steady flow. The bursts are the source of 80% of the infections, and happen in crowded, indoor spaces, with poor ventilation, and the people talking, shouting, singing. The key strategy to stop the transmission of this virus remains to Identify the Infected, and Isolate them while Contagious. This property of the virus means that the best path to Identify the Infected is to seek out emerging large outbreaks, the so-called super-spreader events.
- All indicators at this time point to a very worrisome rise in COVID-19 in our community. Cases are clearly on the rise, we are hearing of outbreaks across different spots in our local communities, and the season of cold dry air, packing indoors, is upon us.
As we enter the fall and winter, as COVID-19 begins to rise up here at home and across the nation, we will remain ready to share information as it unfolds, offer care as it is needed, and to continue to promote the use of the only safeguards we have in our hands: wear a mask, keep your distance, stay away from groups indoors, reconsider participating in team sports.
This is indeed a year, or two, of a great and dangerous pandemic, we need to sustain our strength and commitment to be thoughtful for as long as it rages, even if that is a year or two.
To your health,
Dr. Arthur Lavin
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