• Original Articles By Dr. Lavin Featuring Expert Advice & Information about Pediatric Health Issues that you Care the Most About

    COVID-19 Update July 25, 2020: What Have You Heard about Herd Immunity; Alerts for Cleveland; Our Current State

    By Dr. Arthur Lavin

    The Illness COVID-19 is Spreading Rampantly Across the Country and is Causing Very Severe Illness

    Glossary

    • 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.

     

    Spreadability

    Our Current Situation

    COVID-19 seems a strange, awful, imposition on all of us, and it is.  But it also has a key feature of familiarity- like any problem any of us faces, it goes away much faster if you solve it.

    It pains me deeply to report in this update that our nation continues to choose not to solve the fundamental problem of this pandemic:  Can a nation stop the spread of this virus?

    The answer to this question, now 8 months into pandemic is a very clear yes.  As of  right now, 47 nations have stopped the spread of the virus well enough to see essentially no deaths from the disease.

    And the fact remains in our beloved country, we have chosen not to stop the spread.   One glance at the graphs of daily cases proves beyond doubt, this virus is spreading, spreading wildly, spreading widely.  At times as many as 40 states are experiencing increasing transmission, known sites of transmission including prisons, long-term care facilities, meat packing plants, continue to spread the virus at a tragic clip.

    Even in our office, we have seen in the last week or two a clear emergence of COVID-19 in children, even very young, all well, but the trace of infection in our community is visible to us.

    A different path is in our grasp, right now: a path in which we try to identify everyone in the country who is infected, trace everyone within 6 feet of each and test them, and then isolate everyone, every day, found to be infected, outside their homes.   As noted in most of these posts, that would end the crushing loss of life we are all seeing explode in front of our eyes.  We have watched catastrophe hit NYC, then Chicago and New Orleans, now the South and the Southwest.  Remember Dr. Osterholm’s view on our interview- he is nearly certain that such outbreaks will be experienced by all of us, in all parts of the nation.   Making it all the more urgent to change to this path, to stop the spread.

    As for Ohio, we remain hovering.   For almost all of July, our daily case count has been about 1,000-1,500, it was close to 1500 yesterday.  One thousand is an important level of contagion.  In populations that have far fewer than 1000 cases a day, the spread can explode into exponential growth anytime, but that will take some weeks.  Once you hit 1,000, doubling cases pops you into an exploding epidemic rapidly, so it is in that sense we are hovering.   My own sense is that the SARS-CoV-2 virus is spreading quite widely in cities of Ohio, including our Greater Cleveland area.

    This link shows current Ohio trends, you will see how for some time now the virus is transmitting more widely!  https://www.nytimes.com/interactive/2020/us/ohio-coronavirus-cases.html#cases

    This link documents that Dr. Brix shares my sense that the virus is transmitting widely right here in our neighborhoods: https://www.news5cleveland.com/news/continuing-coverage/coronavirus/report-cleveland-one-of-11-cities-white-house-warns-needs-to-take-aggressive-action-in-fight-against-covid-19

    Have you Heard of Herd Immunity?

    I think most people have.  After all, most discussions of the pandemic talk about how it will continue until  we have a great vaccine (see below), or reach herd immunity.  I think most of us have a sense that herd immunity refers to the notion that if everyone gets a disease, at some point the disease will stop spreading, and that sense is accurate.

    Memory and the Herd

    The idea of herd immunity requires that an infection leave a person unable to get the same infection twice, or at least very unlikely to get sick twice.   So let’s start there, how does that happen?  The answer comes in one word: immunity.  A great feature of our immune system is that it creates memories, as surely as our minds.  I had measles as a kid, it was a long time ago, but right now, it is almost certain that circulating around my body and tissues are special cells of my immune system that carry the memory of that long ago fever, and those cells are called T-cells.  Every T-cell responds to one and only one molecule, in this case, I  have a few T-cells in my body that will activate should a particular protein of the measles virus show up.  My body makes sure this set of T-cells is always around, even reproducing this set as they age, so decades later, if a measles virus shows up, that T-cell will recognize it immediately, and within hours galvanize and attack that will obliterate any measles virus in my body.  That means I won’t get measles twice.

    And this is how all memory in our immune system works.   Sadly, it takes many days for our immune system to wipe out an enemy germ if it is not recognized, leaving plenty of time for me to get sick from that germ.  But, if it recognizes the germ, whamo, it is gone, and I don’t get sick.

    Not every germ creates long-term memory.  The famous RSV germ, which causes a vast number of colds, induces little memory, so I can get a cold from the same RSV virus, every month in the winter, over, and over and over.  There is therefore no herd immunity with RSV.

    Now let’s say we have a germ that creates long-term memory, like measles, or chickenpox, or mono, or many other germs.  And let’s say everyone on the planet gets this germ all on one day.  Then that would mean everyone on the planet will have memory of that germ, everyone, for the rest of their lives let’s say.  So that means in a month or so, and in a year, and in 20 years, if  that germ tries to infect anyone on the planet, it will fail.  And that would mean that disease will end.

    But no germ can infect everyone, and certainly not at the same time on one day.  So in real life, new germs can spread quite well from one person with no prior memory of the infection to another.

    Now, let’s say you live in Covidville, a nice town that has been so healthy until 2019.  And let’s say 100,000 people live in Covidville.

    In March of 2019, 10,000 people came down with COVID-19, half got sick, half did not.   All 10,000 recovered, and developed strong immune memory, these 10,000 people can’t get COVID-19 again.  But the other 90,000 nice citizens of Covidville can.  So in April, the SARS-CoV-2 virus will find new people who have no memory of the infection, and infect them, making half sick.

    I think of viral waves in a population like a fire burning wood.  Think of a burning log, fire only happens if heat burns as yet unburnt wood.  Once all the wood is burnt, the fire goes out.

    And so it is in Covidville, the virus spreads only until it has burned through enough citizens to start to struggle to spread anymore.  Once everyone is infected, there is no more “fuel” and the “fire” burns out.

    Now, do all 100,000 fine folks of Covidville need to be infected for the virus to be no longer able to find someone to infect?

    Or maybe only half the town needs to be infected to make it hard for the virus to spread?

    The answer lies in how contagious the virus is.  One of the most contagious viruses is measles, the average infected person will spread it to 12 others!  That would mean, if the virus could start with one person, then go to 12, then go to 144, after just 9 rounds, over 5 billion people, nearly the whole planet, would be infected.  We saw this when Europeans infected the first Native American with measles.  No Native American had immune memory of the measles germ, so the virus could infect everyone in America, and did.  In short order, about 95% of the native population in many areas died.

    Herd immunity is achieved when the number of people with long-term immune memory to a germ rises to a level that the germ has trouble finding someone it can infect.  For measles, herd immunity only happens when 90% of a community is immune, that’s why we see measles outbreaks when immunization rates drop below 90% in a town or country.

    Most germs don’t spread nearly as well as measles, so if far fewer than 90% of people get immune memory, that less spreadable virus will struggle to jump to someone not  yet infected.

    No one knows that number for COVID-19, but most agree, given it’s infectivity, that that number is somewhere around 60-70%.

    But here is another key item we don’t know- if someone gets infected with SARS-CoV-2, will their immune memory be excellent and lifelong like measles, or will memory even fail to develop at all, like RSV?  We have no idea.  The virus has been around for such a short time, even now, that we don’t know about too many people who had the infection to see what happens if they are exposed.

    So for the herd immunity concept for COVID-19, the first question is if long-term immune memory occurs after infection?  If not, then there can be no herd immunity, because then the virus can infect anyone, even those previously infected, and will never run out of potential victims.

    But let’s say you get good immune memory after infection, and say it lasts a few years, and that our guess is right, once 60% of a population is infected, this virus will struggle to spread, then we would say herd immunity is achieved once 60% of a community is infected.

    For reference sake- the United States, even with high estimates of cases, has hit about 14% infected.  If we don’t achieve herd immunity until 60% of us have been infected, we have a long way to go until herd immunity stops this virus from spreading further.  This is why, in history, most pandemics last 2-3 years, it takes that long to hit 60% or so infected.

    Schools

    The school issue becomes only more heated as the first day of school approaches.  This makes great sense, after all, one thing will be  determined for sure on the opening day of each school:  will that school open?  if open, who will attend in person?

    Many, many urgencies pile on when thinking about opening a school, and whether to attend a school.

    A partial list includes:

    • The life and well-being of our children, teachers, school staff, parents, community
    • The education of our children
    • The mental health of our children, teachers, school staff, parents, community
    • The nutrition of a vast percentage of our children
    • Many other considerations

    Readers of Real Answers already know our view on these competing interests, but it is clearly time to repeat this stance.

    I start with the most pressing reality of this moment- the most deadly epidemic of disease of our lives is currently spreading around the world, and for the foreseeable right here in our Greater Cleveland community. I urgently feel the most compelling priority is to prevent needless loss of life and to prevent needless severe harm to everyone in the community.  Once again we turn to Dr. Osterholm’s most tragic observation in our interview with him– as the pandemic rises to infect what the herd immunity discussion above predicts will be around 60% of America, given our current approaches, then it is very likely each of us will lose someone we are very close to.   This is very, very serious.

    And given the seriousness of the potential loss of life, I think it most urgent, as the first step, to not gather indoors with people not isolated in your household, until the transmission of this deadly disease is interrupted or halted, or ends.  Yes, it may be 1-2 more years (see vaccine update below) before we reach this goal, but it won’t be forever.  A storm is in our midst, it only makes sense to take precautions.

    To my mind, the danger of dying from this disease or suffering terrible harm is far greater than the harms that might come from avoiding such fates.   The issue comes into focus when we consider recent reports that teachers, compelled to report to school or lose their job, are rushing to write their wills.

    To be specific, when it comes to schools, I would recommend seeing what the level of viral spread is on any day you think of sending your child to any school.  If COVID-19 spread reaches a level of activity, or is at risk of rising out of control, I would not attend school.  And in such communities, if I were in charge of a school I would not open it.

    I believe our nation’s #1 priority is to stop the spread of the infection, now.

    Vaccines

    In a prior post we discussed the latest news on the m-RNA virus from Moderna, and how well it worked in the first 45 people tested.

    Today, we discuss the new vaccine for COVID-19 being developed at Oxford, England- https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31604-4/fulltext

    We start by observing that the Institute at Oxford where this work is based is the Jenner Institute, named after the person who developed England’s first immunization, the smallpox vaccine.  That work led to smallpox being eliminated from humanity.

    The basic idea of this vaccine is similar to Moderna’s m-RNA vaccine.  In both ideas, a bit of genetic material is injected into a person, and that person takes up the bit of genetic code, and that code directs that person’s cells to make a protein only found on the SARS-CoV-2 virus, one of its spike proteins.  Once your body is making these spike proteins from COVID-19, your body will make antibodies, and hopefully (see above) long-term immune memory, so you can’t get COVID-19.

    In the Oxford genetic vaccine, instead of the mRNA code for the spike protein of COVID-19, a more complex brew is assembled.

    This team took a common virus, called adenovirus, which is well known to really provoke the immune system, and is using this virus to get your body to notice the immunization.  To make sure their adenovirus doesn’t actually infect you, the Oxford team started with chimpanzee adenovirus and then altered it so it can no longer copy itself, i.e., it can’t reproduce.

    Now they took this chimp, weak, adenovirus, and attached it to the gene codes for the COVID-19 spike proteins.  This little package is the Oxford COVID-19 vaccine.  How does it do?

    They immunized 88 people with their vaccine which has the very technical name “ChAdOx1-nCovid-19”, but I will call it the Oxford vaccine.  They also immunized over 500 people with the same meningitis vaccine we give 11-20 year olds as a control.

    Both the Oxford and control immunized had sore arms, and some fatigue and malaisse, but no more serious side effects.

    All 88 immunized developed jumps in antibody to the COVID-19 virus, including antibody to the spike protein and neutralizing antibodies.  All also demonstrated T-cell activation, which bodes well for the chance long-term immune memory is being created, bit the study only went out 56 days, so we do not know about long-term immunity from this vaccine.

    BOTTOM LINES

    1. Our nation, our state, our local community here and around Cleveland, is suffering from a continued, highly active, spread of COVID-19.  Everyone of us can catch this disease as of now.   Many who get infected will be fine, particularly the young.  Many of us who will get infected may come to serious harm, even dying.  The threat of harm is dramatically lower in the young still, but not absent.
    2. As long as this virus, so dangerous, is spreading actively, our nation has a #1 priority to attend to, stop the spread.
    3. Until our nation achieves this goal, each of us should be sure to take steps to avoid catching this potentially deadly, and harmful, disease.   The best way to not get infected is to stay as isolated as possible, second best is staying 6 feet away from everyone and wear a mask and wash hands frequently.
    4. With regard to schools, the answer should be defined by these first 3 points.  In any community where spread of this deadly virus is high enough, schools should not re-open, and parents should not send their children to schools that are open.  As of today, I would see current levels of spread of this virus as high enough to trigger this caution.   We all are forced into monitoring the level of spread every day, every week, every month, to decide if it is high enough to avoid any public gatherings, including schools.
    5. Herd immunity is defined by if an infected person can get infected with COVID-19 twice or more.  If not, then it is further defined by how well the virus hops from one person to another.  IF people infected don’t get infected again, then it looks like once about 60% of a community is infected, spread will be slowed and interrupted.
    6. We now have two vaccines for COVID-19 with peer-published results that establish the idea of injecting a bit of genetic code to have your own body make a protein your immune system will react to that might protect you from COVID-19.  We still DO NOT KNOW if either of these vaccines will really work, or be safe.  That is, we don’t know if we gave either to a billion people if those billion would be safe from getting COVID-19, and come to no harm for receiving either vaccine, but it is hopeful that two models passed their first test in people.

    For now, we repeat that COVID-19 is here in our communities, and it is actively spreading.  Please be safe, be very careful, be well,
    Dr. Arthur Lavin

     

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