Episode 1 – Intro to SARS-CoV-2
Dr Daniel Griffin MD, PhD – gives an introductory comprehensive talk about the pandemic coronavirus SARS-CoV-2.
Dr Daniel Griffin is a Physician-Scientist and Chief of the Division of Infectious Disease at ProHEALTH New York, and a clinical instructor of Medicine at Columbia University’s Irving Medical Center. He is President of Parasites Without Borders, a co-host of This Week in Virology (TWIV) and active in the clinical care of patients living in the New York area and has been particularly involved in the care of patients suffering from COVID-19 since the very beginning of the pandemic.
Viruses and coronaviruses are defined, we talk about the origins of SARS-CoV-2, discuss what a pandemic is and why we are in a pandemic, the transmission and contagiousness of this coronavirus, the variants of concern with a focus on Omicron and a look to the future.
https://parasiteswithoutborders.com/
Transcript
Kojala Medical presents COVID 19 the answers the show that delivers the scientific evidence-based
Speaker:knowledge that can safely return us all to our pre-COVID lives my name is Dr Funmi Okunola and
Speaker:I'll be hosting the show every week you can listen to me interview a highly respected professional
Speaker:about the science that can reduce your risk of becoming infected with this coronavirus
Speaker:hello listeners and welcome to episode 1 of COVID 19The Answers. I'd like to
Speaker:introduce you all to Dr Daniel Griffin. Dr Griffin is a physician scientist, an MD, PhD
Speaker:chief of the division of infectious disease at pro health New York
Speaker:the senior fellow for infectious disease at united health group and a clinical instructor of medicine
Speaker:at Columbia University's Irving Medical Center where he is also an associate research scientist
Speaker:he is a speaker and educator who has lectured throughout the world on global health topics
Speaker:and he is president of Parasites without Borders and a co-host of the podcast this week in virology
Speaker:or TWIV of which i am an avid fan and is really one of the inspirations for this podcast series
Speaker:Dr Griffin is active in the clinical care of patients living in the New York area
Speaker:and has been particularly involved in the care of patients suffering from COVID 19
Speaker:since the very beginning of the pandemic he's going to talk to us today about SARS-CoV-2
Speaker:the virus that causes COVID 19. Welcome, thank you, happy to be here. Really happy to have you
Speaker:right, so getting right down to bare basics and the questions SARS-CoV-2 is a coronavirus
Speaker:so while the medical and scientific community understand what a virus is
Speaker:the non-medical people likely don't know so what is a virus and why do they exist
Speaker:now this is a great place to start so what is a virus there's there's
Speaker:several ways to go about this you know us as scientists have our very sophisticated answer
Speaker:um you know but then i think let's try to make it something that's um accessible so you know most of
Speaker:us have been sick we felt not wonderful you know, we we refer to them oh what bug am I fighting off
Speaker:and in that context there are several different pathogens several different things out there
Speaker:that can make us sick this one of the simplest of them is the virus the virus is an organism that
Speaker:really is a parasite it can't do everything itself it actually has to co-opt the machinery of our
Speaker:cells to make us sick to make animals sick to make plants sick even you know we'll talk a little bit
Speaker:maybe later about the types of viruses but this is one of the simplest in distinction from a bacteria
Speaker:which a little more complex they can actually live without us on their own we have the the funguses
Speaker:um which actually you know sometimes we use them to help us brew beer maybe with wine things like
Speaker:that uh cheese and the like but sometimes they can make us sick as well but that's
Speaker:really where viruses fit in they're they're one of the three major things that can make us sick
Speaker:uh one of the simplest that's the virus a little more complicated the bacteria and then even a
Speaker:little more complicated the fungus oh thank you for that now we understand what a virus is
Speaker:what is a coronavirus and what makes it distinctly different well now we we dive a little bit deeper
Speaker:and this is okay so the way we understand viruses is there's really i'm going to say
Speaker:two parts to a virus there's the inside there's the outside the inside is the genetic material
Speaker:and we really break viruses down into viruses that have RNA as their genetic material viruses
Speaker:that have DNA as their genetic material the coronaviruses they fall into that group where they
Speaker:use RNA as their genetic material so that's what's inside but what's on the outside this is where
Speaker:the name comes from on the outside of that inner package is the capsid um it's a protein capsule
Speaker:that surrounds that genetic material now some viruses also have a lipid envelope around that
Speaker:and that lipid envelope for the coronaviruses if you look at it under an electron microscope
Speaker:because these are incredibly tiny it actually looks like the corona of the sun there's actually
Speaker:these spike proteins that surround that capsid giving it this appearance giving it this name
Speaker:so the corona viruses most of us actually have encountered them before a number of
Speaker:those common colds that plague us are common coronaviruses in this case SARS-CoV- 2 is one of
Speaker:those coronaviruses that was not so common now i think it's becoming common but makes us quite ill
Speaker:oh that's excellent Daniel thank you um SARS-CoV or SARS-CoV-1 entered the public light in 2003
Speaker:with much publicity but seemed to disappear reasonably quickly in comparison to sales copy 2.
Speaker:so how is SARS-CoV-2 different from SARS-CoV- 1 what is the genesis behind the two SARS viruses
Speaker:and why well actually you've already answered why they have this name
Speaker:so this this is a great question and i think there's there's a lot that we we've learned in
Speaker:the last two years we were lucky with SARS-CoV-1 um so just to start where do they come from we're
Speaker:going to get back to this again there are a lot of these coronaviruses that are out there in nature
Speaker:they're in other animals a large number of them are in bats some of these type of viruses are in
Speaker:camels and and little furry mammals and the like um one of the nice things about sarsko v1 was that
Speaker:people were not contagious until they were quite sick they would start to feel horrible they would
Speaker:end up in the hospital then they were contagious there are small subtle changes with SARS-CoV-2
Speaker:enough to make it actually a different virus where people start to be contagious before they
Speaker:start to get symptoms before they start to feel ill and that's really been the achilles heel for
Speaker:us that's been the disaster SARS-CoV-2 though it made people quite sick though there was a
Speaker:really high chance of death those people were not contagious until they were in hospital until we
Speaker:could keep them isolated until we could stop that transmission but as we've seen with SARS-CoV-2 as
Speaker:we've seen with people that have COVID 19 about half of the transmission is occurring either
Speaker:before a person becomes symptomatic or while they have no symptoms at all yes yes that's right
Speaker:ah the um the general feeling in the community by the media and government
Speaker:seems to be portraying SARS-CoV-2 to be the same as catching a cold or the flu
Speaker:how would you compare catching SARS-CoV-2 to the flu or a cold why isn't this the flu
Speaker:so i think that a lot of people who are vaccinated who are healthy you know that that does change
Speaker:things but i think people have to keep that memory it's only two years ago let's remember
Speaker:when people were getting this they were not vaccinated we didn't have great therapeutics
Speaker:and what was happening about one in five twenty percent of people were ending up in the hospital
Speaker:that's not the common cold that's not the flu we're seeing about one in every 50 people
Speaker:we're dying um just here in New York we were seeing over 2 000 deaths in a single day
Speaker:again not the common cold now here we're seeing this latest omicron wave in a lot of parts of the
Speaker:world Canada the united states parts of Europe not as many places in Asia or in Sub-Saharan Africa
Speaker:but areas where a lot of people are vaccinated if a vaccinated person encounters SARS-CoV-2 to
Speaker:gets COVID 19 it often can feel like just a bad cult but for the unvaccinated individuals we are
Speaker:still seeing a lot of hospitalizations a lot of deaths with the omicron wave the week for which
Speaker:we have the most recent data for children here in the us we were seeing three children dying per day
Speaker:we have seen hundreds of children die during the omicron wave
Speaker:we actually reached a peak of over 3 000 deaths in a single day in the united states
Speaker:from omicron certainly not a mild common cold that can kill 3 000 people in a single day
Speaker:thank you so much for reminding us of that situation in those numbers and to
Speaker:think of the suffering of well everybody but in particular children is truly heartbreaking
Speaker:moving on um there's been a great deal of speculation around the origins of SARS-CoV- 2
Speaker:ranging from animal to human transition in an animal market to a man-made virus produced in a
Speaker:lab what are the origins of SARS-CoV-2 in your opinion yeah so i think this is one of those
Speaker:tough questions and there's unfortunately a lot of political aspect to this um so let's focus on
Speaker:what we know let's focus on the science because it is an important question we do want to know
Speaker:where this came from because we are concerned that there may be future pandemics in many ways
Speaker:a lot of us are concerned this may have just been a warning shot over the bow we may be facing worse
Speaker:pathogens worse pandemics in the future some of the early discussions were focused on this idea
Speaker:that you could look at the virus and see clues suggesting that it had been made in a lab made
Speaker:by human beings um you know when we've actually looked at we're not seeing that that's true and
Speaker:a lot of the scientists who initially were quoted have gone back and said you know when you actually
Speaker:look at it no one of the big things that people looked at was this furin cleavage site a word that
Speaker:i used to think only virologists would use but now it's something that's bantered over you know
Speaker:the holiday table with family initially this was some smoking gun but we now realize almost every
Speaker:subclass of the coronaviruses have furin cleavage sites that's nothing atypical that's nothing
Speaker:shocking we at this point have moved to where we realized this probably came from an animal source
Speaker:perhaps from a bat interesting enough the people who are still focused on the lab so well maybe
Speaker:that bat first went to the lab and then someone took it home and gave it to someone else well
Speaker:no evidence actually that that happened um what we suspect is that this is a virus that has been
Speaker:circulating in bad populations in southeast asia at some point it got into the human
Speaker:population when we have our scientists look at these animals when we do these animal sampling
Speaker:it looks like there are potential other viruses that can cross over from animals so
Speaker:i do think this is an important question not only where did this virus come from
Speaker:but also what are the viruses are out there in nature lurking I do not think this was created by
Speaker:a scientist or any way a malicious mad scientist attack upon humanity. Thank you for that and
Speaker:and i don't i know you're not a zoologist, but bats do contain a lot of carry around
Speaker:a lot of viruses that could be dangerous to us but have no effect on them i think it would be
Speaker:interesting in the future and i think there are studies looking at that because it might
Speaker:bring clues to how we could protect ourselves uh against the immunity that they seem to have
Speaker:yeah i would agree wholeheartedly bats bats are fascinating i actually find them quite cute
Speaker:but no they they're quite different than us because they're so metabolically active
Speaker:they have a whole different immune system uh they have a whole different interaction with
Speaker:viruses with illnesses um and you know i think unless we uh really put our resources um into this
Speaker:ahead of time we're gonna end up putting a lot of resources into this after the fact um during
Speaker:another pandemic indeed um you've answered that question i'm not sure the public distinguishes
Speaker:between SARS-CoV-2 and COVID 19 please help us to understand the difference between the two ,
Speaker:yeah i i it would have been nice if we all got together and planned the naming
Speaker:a little bit better so it's it's always nice like with polio you have polio disease
Speaker:polio the virus um but uh in in this case um initially the terminology was novel coronavirus
Speaker:and then it ended up getting you know named as a disease COVID but the virus and so here's
Speaker:here's really to cut to the chase the virus that makes us sick the name of the virus is SARS-CoV-2
Speaker:the disease the i'm sick i have the COVID 19 so COVID 19 is the disease
Speaker:SARS-CoV- 2 is the cause of that disease thank you for that clarity
Speaker:we toss around the word pandemic as a description of what we have experienced in the last two years
Speaker:to help us understand the current global situation let's start with the definition of a pandemic
Speaker:what is a pandemic okay certainly um you know my dad always tells me like think about what
Speaker:the words mean and we can break this word down and really pan is the big thing that helps us here pan
Speaker:is really referring to something that is involving the whole world much of the world all around
Speaker:not just a localized epidemic so that's really the distinction we're making an epidemic would
Speaker:be if there was a problem just in canada for instance a pandemic is when you start involving
Speaker:many many countries when it starts to become around the world but there's another distinction
Speaker:in here which everyone is really starting to ask about now when does this go from not pandemic
Speaker:to epidemic but when does it go from pandemic to endemic when do we stop having these huge surges
Speaker:that overwhelm our health care systems um when do we stop having people show up at ERs and they
Speaker:can't get treated with a twisted ankle or having a heart attack or you know some other horrible thing
Speaker:and that has a lot to do with getting those numbers down and getting numbers to a predictable
Speaker:level where we have expectations um and are able to bring resources to bear to do that we
Speaker:are thinking in many parts of the world we may be making that last transition we don't think SARS-
Speaker:CoV-2 is ever going to be localized to just one part of the world so the pan part but we
Speaker:do think it's going to transition from a pandemic level to an endemic level probably settle into a
Speaker:seasonal pattern where in certain parts of the world the times that more people are inside and
Speaker:together let's take the rainy season in certain parts of the world let's take the winter in other
Speaker:parts of the world where people are inside we'll be seeing higher rates then times when people are
Speaker:outdoors the dry season the summer then we'll be seeing lower levels and a lot of this is based
Speaker:upon our understanding of how this transmits the fact that this is a respiratory viruses
Speaker:and many of the coronaviruses with which this is similar have settled into that seasonal pattern
Speaker:so do you think that we're at that stage now do you think that we're at the endemic stage now
Speaker:i think we're nearing it in certain parts of the world and i think that that's the big challenge
Speaker:for us when i say in certain parts of the world with the latest omicron surge um here in in the
Speaker:west here in Canada and the united states actually much through Europe as well we have a large
Speaker:percent of people now who are either vaccinated or recently infected we have a lot of therapeutics
Speaker:on the horizon just increasing access that will allow people should they get infected to stay out
Speaker:of the hospital again getting it below that limit that's going to overwhelm our health care systems
Speaker:but still that inequity there's many parts of the world where they're continuing to do
Speaker:everything they can to be safe but they don't have that great advantage of access to vaccines
Speaker:and while that continues that puts not only those individuals at risk but the rest of the world at
Speaker:risk at risk of more variance more challenges to that wonderful protection that vaccines afford us
Speaker:i see so even though the rates of hospitalization are high at the moment the death rates are high
Speaker:in places like the state you think we're moving towards an endemic phase at this moment in time
Speaker:i i think we're moving i don't think we're there yet i think that's really important
Speaker:we're not there yet but we are moving um i suspect we'll get a little bit of a bump we
Speaker:have a big athletic event coming up here in the us and whenever we have a holiday whenever we
Speaker:have a reason for a bunch of people to be all gathered together we see a little bit of a rise
Speaker:but we are heading towards warmer weather we're expecting numbers to come down for a while but
Speaker:we do expect numbers to rise again next fall and when they do rise instead of people ending up in
Speaker:the hospital some people will be able to stay out because they've been vaccinated some people
Speaker:will also stay out because they'll have access to medications therapeutics that keep them out
Speaker:you know hopefully as we move forward those numbers will keep moving in in the right
Speaker:direction so i see where you're coming from and how there's the difference so basically if
Speaker:you're in a rich western country well-resourced country that has access to vaccines readily
Speaker:treatments readily you can you feel that there can be an exercise on the control of of of the virus
Speaker:we can somehow minimize the outbreaks or possibly even eliminate them if we have a high enough
Speaker:proportion of the population vaccinated i'm am i correcting in as painful as it is the way you word
Speaker:that you're worrying it correctly um in privileged parts of the world where we have the ability to
Speaker:vaccinate not only once but twice but now three times certain higher risk people maybe
Speaker:even a fourth vaccine where we have access to therapeutics that might be six or eight hundred
Speaker:dollars or even two thousand dollars for a course talking about the antivirals and the monoclonals
Speaker:it's a much different situation than some parts of the world where less than one percent of
Speaker:the population has access to vaccines where those expensive therapeutics are out of reach
Speaker:so really a lot of inequity here that we really need to address thank you for
Speaker:that clarification excellent answer really um we've had three pandemics in the last 20 years
Speaker:HIV aids which is ongoing from the 1980s and i know as a research specialist research area for
Speaker:yourself H1N1 swine flu influenza in 2009 and now COVID 19. how are these pandemics different from
Speaker:the 1918 to 1920 Spanish flu or the bubonic plague of the 14th century that have occurred previously
Speaker:all right so we're going to need a whole podcast for just that question but let's go into it
Speaker:sorry no no this is for and i really appreciate that you bring this up
Speaker:let's start with HIV aids um it's really tough i still remember seeing a movie surviving the
Speaker:pandemic and i was quite shocked because this pandemic that pandemic it is not over
Speaker:there are over 30 million people in the world living with hiv in the united states we have
Speaker:over a million people living with hiv this is not a pandemic that we've gotten through
Speaker:we continue to see large numbers of people getting infected every year we continue to see hundreds
Speaker:of thousands of deaths so we are still in that pandemic what was really tough about that pandemic
Speaker:was this us them view this idea that this was not our pandemic that it was a pandemic of
Speaker:other people that somehow it was those people's fault i think that was an incredible challenge
Speaker:I personally grew up in Greenwich village my mother was very involved with activism
Speaker:uh worked with some of the act up activists work with a young Anthony Fauci at that point
Speaker:um so very personally still very troubling to me that that people don't remember that
Speaker:people don't realize that this is an ongoing challenge so thank you for bringing that up
Speaker:those were some of the differences right it was not a respiratory pathogen
Speaker:it was not embraced as our problem as a global community hopefully that is improving now let's
Speaker:move to influenza that was slightly different and actually has a lot of similarities here right
Speaker:respiratory virus it was actually not just um focusing on elderly but we're actually seeing
Speaker:younger individuals dying at higher rates than we were used to with uh prior influences
Speaker:this is something also that got to the point where it was stressing but not overwhelming our
Speaker:healthcare systems but what did we have lots of experience with vaccines we had therapeutics it
Speaker:was a disease that we were familiar with not as frightened by we understood transmission
Speaker:a lot of big differences when we ran into COVID 19 there was a lot of fear
Speaker:there was a lot of panic and there still is people throwing different therapies at it
Speaker:just hoping wanting to believe desperately that they could make a difference really
Speaker:quite a difference and going back to the 1918 well that's kind of very similar to what we experienced
Speaker:and are still experiencing a lot of fear there were no vaccines there were no therapeutics
Speaker:not even quite sure about how it was being transmitted there were there were masks there
Speaker:were even anti-mass protests there were really a lot of similarities and actually we're seeing sort
Speaker:of the tail end similarities people talk about how that uh influenza pandemic ended but people
Speaker:continued to die when people had just finally reached a point where they were exhausted they
Speaker:no longer wanted to hear or read about it or take any more measures so unfortunately i think we're
Speaker:we're reaching that social exhaustion phase here while COVID 19 in the US is still on some days
Speaker:killing over 2 000 individuals wow wow and i guess with the bubonic plague the numbers were just
Speaker:phenomenal i think the numbers of deaths i think they went into the hundreds of millions wasn't
Speaker:yeah i mean the bubonic plague overwhelming in many ways um just because the mortality
Speaker:was so high i mean some estimate a third of people in Europe died but then again
Speaker:we had bubonic plague in china while the west was busy fighting world war one the chinese asked for
Speaker:assistance we couldn't offer any because we were busy doing what we were doing so bubonic plague is
Speaker:you know we always hear about it think about it and focus on europe but this was a global issue
Speaker:well i didn't realize that about china and thank you again for another excellent answer um okay
Speaker:we now understand what a pandemic is and how the current pandemic is different from past pandemics
Speaker:at the initial stage of the pandemic there was so much unknown about the transmissibility of
Speaker:the virus and public health initiatives were inconsistent and often lacking specific direction
Speaker:we now know more about the virus with that in mind in your opinion how is sales cov2 transmitted
Speaker:so i think one of the biggest challenges and one of the things i hope we learned from this
Speaker:pandemic is the importance of of communication say science communication public health communication
Speaker:this is a respiratory virus you don't get this by surfaces it's
Speaker:very uncommon that it's spread by surfaces you don't get this by swimming in a pool
Speaker:you get this bite breathing you get this this is a respiratory virus and you acquire it by
Speaker:exposure to your respiratory system um breathing it into your nose breathing it into your mouth
Speaker:so i i love the there was an article by roxanne comcy where she says it may not be airborne but
Speaker:it's borne by the air this distinction of airborne is is a very confusing scientific
Speaker:in-hospital infection control distinction that just did nothing but muddy the waters
Speaker:if you are a little bit away you decrease your risk to some degree you get a little farther away
Speaker:that's better but once you get in a closed indoor situation nowhere's safe it's circulating around
Speaker:most of our transmission we realize probably is occurring in these indoor settings because what do
Speaker:people do indoors they breathe there isn't great ventilation there isn't great dilution effects
Speaker:um so yeah this is a respiratory virus i do want people to keep washing their hands but to be
Speaker:honest it's the breathing air particularly in a closed indoor space with someone who is infected
Speaker:someone who is letting the virus out we do know that really really high concentrations are in
Speaker:your nose so when we're asking people to mask if you're not covering your nose you're not wearing
Speaker:a mask very excellent point um and i do see the 25 percent of people wearing their masks under
Speaker:their nose so thank you for making that that point um and also we uh we have professor uh
Speaker:jiminez coming uh on uh later on in the series to talk all about uh uh saskov to uh in the air
Speaker:oh that is fantastic um and white i'm just getting to the at the start of the pandemic um the r
Speaker:naught for ancestral sarsko v2 was two to three versus the highly contagious measles at 15 to 18.
Speaker:today with omicron the virus is rated second only to measles in terms of contagion with an r naught
Speaker:of 8 to 15. in simple terms how would you explain r naught and rt the transmissibility measurement
Speaker:okay so this is i think really important and you know maybe another silver lining of the pandemic
Speaker:is everyone is interested in learning these things um so r is just short for reproductive number and
Speaker:really if a person one person has the infection on average how many other people do they spread it to
Speaker:but it gets a little complicated so we'll go into that the r naught is when you know nothing and
Speaker:do nothing so it's no mitigation no masks no medicine no vaccine so are not is what is the
Speaker:average from one person how much are they going to spread without any mitigation so that or not
Speaker:is only going to exist early on in wuhan china before we figure out anything about the virus
Speaker:r sub t is what is going on at this specific point in time and these are hard to calculate because
Speaker:one thing we haven't really talked about is the reproductive time the time of that reproductive
Speaker:cycle so let's take the original wuhan ancestral strain original estimates before we knew what
Speaker:was going on was that on average one person would infect two to three other people so that was the
Speaker:r naught the reproductive number then on average those three people would each infect another three
Speaker:people you're up to nine before you know it the reproductive time was about seven days from the
Speaker:time that first person was exposed to the time they could spread it to the next group of people
Speaker:what we've seen and a huge issue with omicron is with each new variant that reproductive time has
Speaker:diminished so if you start asking in the original ancestral strain in about a week one person would
Speaker:on average spread it to three people but now we're seeing that with omicron that reproductive time
Speaker:has dropped to probably only about three days maybe three to four so in that one week it's
Speaker:had a chance to have two reproductive cycles so even if you still stuck with that original three
Speaker:now it's had a chance to do that twice you're up to nine from a single individual
Speaker:in just a matter of a week so the rt per week can appear to be tripled um one of the challenges
Speaker:um is that we are seeing over time the shortening of that reproductive time that r sub t can be
Speaker:changed can be challenged by vaccines we can reduce it with masking and a lot of other measures
Speaker:that was fantastic you've i'm learning so much in this program too that's the clearest
Speaker:answer i have ever had thank you daniel um there are three different phases of contagiousness with
Speaker:this coronavirus talk about one asymptomatic two pre-symptomatic and three symptomatic transmission
Speaker:okay so the easiest is to break out the pre-symptomatic from the symptomatic and
Speaker:this is really distinct from the asymptomatic some people never ever get symptoms but those people
Speaker:as we know can still transmit the viruses so let's let's let's go there for starters an individual
Speaker:gets exposed there's a certain incubation time where they've been exposed but they don't have
Speaker:enough virus to spread to another individual as mentioned early on that was about seven days with
Speaker:omicron it may only be three to four then the person reaches a point where they never know it
Speaker:they never have symptoms but they have enough virus that they can spread it to someone else
Speaker:that would be our asymptomatic transmission now the other and this is a challenge for us as well
Speaker:is before you start getting symptoms SARA-CoV-2 can already be at a high enough level that one to
Speaker:two days before you feel bad if you're eventually going to feel bad you can already be spreading it
Speaker:to other people this could be that period of asymptomatic transmission because you don't
Speaker:feel bad you might be going to school you might be going to the office you might be going to that big
Speaker:birthday party for your 90 year old grandmother and so what we now know is that about 50 of the
Speaker:transmission is occurring in those asymptomatic individuals and those pre-symptomatic individuals
Speaker:that still leaves a chunk about 50 percent of transmission people starting to feel bad
Speaker:that first day or two maybe probably out to day five but really diminishing out to day ten when
Speaker:you're not feeling well you're coughing you're sneezing and you again can transmit SAR SCoV 1
Speaker:only was transmitted during that when i feel sick phase influenza again really not much transmission
Speaker:until you feel sick so really this asymptomatic pre-symptomatic i feel fine but can still spread
Speaker:it to others that has really been a disaster and a challenge for us with COVID 19. thank you
Speaker:shifting gears let's move to discussing variants the virus appears to be evolving we started with
Speaker:the original or ancestral strain of sarsko v2 from wuhan there have been many variants but several
Speaker:variants of concern from alpha beta gamma delta to now omicron please help us understand
Speaker:what is a variant and how is this different from a mutation
Speaker:okay well one thing i'll say i think this is really important and this is
Speaker:humility all across the board for scientists we initially looked at coronaviruses and
Speaker:said this is a fairly stable virus we're not expecting changes we're not expecting variants
Speaker:early on it was spreading there were maybe seven changes seen throughout the entire world
Speaker:we thought we we had this beat and then we started to see these changes so let's let's
Speaker:go back to what we all learned about with viruses this is a virus the genetic material inside is rna
Speaker:that rna every three bases of that rna codes for a certain amino acid those amino acids are going
Speaker:to build those proteins and those are proteins that we're all familiar with the spike protein
Speaker:the nucleocapsid right that's that structural protein around
Speaker:the rna polymerase the one that actually we're targeting with some of our drugs now
Speaker:what we have seen over time is there is a certain amount of pressure selection
Speaker:pressure on a random background of changes where a change is actually advantageous for that virus
Speaker:as we talked about one of the advantages might be that instead of it taking seven days to go from
Speaker:one person to the next it might only take five or four or down to maybe three so we start off with
Speaker:changes in the rna that result in changes in the amino acids that result in changes in that protein
Speaker:if the rna changes and you can have changes that are silent that don't change the protein
Speaker:we really don't see them we don't care about them mutations are in the rna amino acid changes we
Speaker:call mutations we probably shouldn't we upset our scientific colleagues but changes in those amino
Speaker:acids people have come to call those mutations that's when we start seeing antibody evasion when
Speaker:we start seeing viruses that can't be neutralized if you recently were infected by delta as we saw
Speaker:when omicron came on the scene so the initial variance of interest we noticed some changes
Speaker:variance of concern when those changes were significant to really change the biology to
Speaker:change the fitness of the virus to either allow it to have a shorter reproductive time allow it
Speaker:to have the ability to evade immunity whether it's vaccine or prior infections thank you
Speaker:why i think you've already answered this um partially this question so um i think you've
Speaker:already answered why saskov2 develops variants do you have any sense of what potential future
Speaker:variants could be you know we we are concerned that there will continue to be variants um because
Speaker:one is we do realize that coronaviruses change over time and it isn't just sars kobe 2. we've
Speaker:really started to look more closely at the other coronaviruses and they change over time
Speaker:the preliminaries it makes errors you end up with a copy of the rna that's a little bit different
Speaker:and sometimes that little bit different can be helpful so
Speaker:what are what are the big drivers now we're seeing a sub-variant of omicron where again
Speaker:slightly shorter reproductive time right so to go from one person to the next
Speaker:maybe even a little quicker than we saw with omicron so that's one bit of pressure
Speaker:the other big pressure that we saw with omicron is the ability to reinfect people who were infected
Speaker:before and also the ability to infect people who were vaccinated but not boosted to try to get
Speaker:around that so we call immune evasion there really isn't a lot of selective pressure to make people
Speaker:sicker it's all about the virus becoming fitter the virus being able to out-compete other variants
Speaker:the virus being able to get into those respiratory niches and make people sick
Speaker:this is such a rich conversation and you know we're so privileged to have a person such as
Speaker:yourself with such specialist knowledge being part of this program really would like to thank you um
Speaker:so the scientific community identifies variants by genomic sequencing
Speaker:what is genomic sequencing and how has it been applied in this pandemic so the timing of this
Speaker:question is perfect because we are celebrating 50 years since the discovery of the reverse
Speaker:transcriptase so what do we do we take the rna and we use this enzyme that was
Speaker:discovered in david baltimore's lab youngest nobel prize winner i think
Speaker:and what you do is you copy that rna to dna and we were able to read the sequence of the dna which
Speaker:corresponds to that original rna really sort of a photographic negative of the rna sequence
Speaker:so around the world thousands of labs millions of sequences have been generated we take one of those
Speaker:samples people are now familiar with either the front of the nose maybe the brain biopsy
Speaker:sample that beautiful test that we do that sample then goes off that genetic material that rna is
Speaker:isolated it's reverse transcribed to dna and then we read the sequence with our sequencing machines
Speaker:these go into these huge databases where they're being analyzed some parts of the world do a
Speaker:tremendous job of generating lots of sequences getting them into these big databases and
Speaker:tracking it so that's genomic we are we are sequencing the genome of this rna virus thank you
Speaker:the length of time from infection to a person being contagious appears to have changed with
Speaker:omicron as you cited a couple of weeks ago on twitter how long does it take for
Speaker:a human being to become contagious with sales coverage ii when first infected now
Speaker:yeah i mean unfortunately now we're seeing and i've touched on this a few times it may only be as
Speaker:little as three days with the ancestral wuhan um variant we were seeing probably about seven days
Speaker:um you know maybe people were a little bit you know contagious a little bit before that day seven
Speaker:but really about seven days between one person and the next with alpha it dropped a little with delta
Speaker:it dropped more and then we're down to three to four from omicron we first started noticing
Speaker:this with well right after a very interesting um ritual celebration event we have here in new york
Speaker:city called santacon where apparently people dress up as santa claus and go from bar to bar
Speaker:this occurred on a saturday night we started seeing positives as early as monday and tuesday
Speaker:really alerting us that something was different about the reproductive cycle time with omicron so
Speaker:really very quickly people were getting exposed within two to three days we were starting to
Speaker:see positive tests appear i've also read some research whereby people get symptoms with omicron
Speaker:are using the rapid antigen tests which show up as being negative and then several days um
Speaker:sometimes when the symptoms are sort of easing they're they're testing positive
Speaker:and this seems to have happened with omicron can you um provide some light on that yeah so i think
Speaker:this this is excellent this will be our public service for people to think about how to use those
Speaker:tests properly um we had a lot of ideas on this um you know early on we talked about how people would
Speaker:be positive for a day or two before symptom onset but now we started to see that people were getting
Speaker:symptoms and then not getting that positive test until the next day early on with the ancestral
Speaker:strain we had higher levels just right before symptoms occurred than when symptoms started to
Speaker:occur when symptoms occurred it was already on the way down recent challenge study in the uk looking
Speaker:at this we had hoped that oh it's because people are vaccinated it's because their immune system
Speaker:is ramping up maybe it's prior infection but that recent data really confirms that this this dynamic
Speaker:the first day that you start to feel crummy is not the best time to go ahead and do that test give it
Speaker:a day see how you're doing it's that second day when you're going to have the best sensitivity
Speaker:for those rapid tests so we have a challenge in our pediatric offices right mom brings in
Speaker:johnny johnny started to feel bad last night and now mom wants to know can he go to school the
Speaker:answer is no the answer is we do a test right away even if that's negative we're going to send off a
Speaker:pcr or we're going to retest the next day when we have our sensitivity so um don't don't think
Speaker:that one test predicts the future think about the timing of when the best time to do that test is
Speaker:and it's really after a full 24 hours of symptom onset okay are we also seeing with omicron that
Speaker:people are contagious for a longer period of time even if if vaccinated um i read somewhere that um
Speaker:from a few specialists on twitter that that we can have a situation whereby when you're
Speaker:vaccinated where you can be contagious for up to maybe nine ten days and if you're
Speaker:unvaccinated possibly up to 20 days um have you do you feel there's any relevance in that
Speaker:so i don't think it's true and i'll tell you why and i think it's great that this comes up
Speaker:one of the things that hopefully and maybe people listen to twiv after this one of the things we
Speaker:always try to talk about is the difference between rna and viable contagious infectious
Speaker:virus so if an individual is vaccinated and they get exposed and they get infected they
Speaker:can still have really high levels of rna they can still have significant levels of infectious virus
Speaker:but what we're seeing is that rna comes down quicker in someone who's been vaccinated than
Speaker:someone who's not and we also see the resolution of infectious viable virus coming down much
Speaker:quicker so i know people are still getting positive antigen tests they're still getting pcrs
Speaker:well out but they're ceasing to have infectious transmissible virus
Speaker:it vaccinated probably after about five days unvaccinated probably after about nine or ten days
Speaker:okay so that makes it very difficult to interpret an antigen test in those scenarios it's really
Speaker:hard to interpret an antigen test to try to end your quarantine so if you start to feel sick
Speaker:and your antigen test is positive for five days you're probably infectious we recommend
Speaker:being careful for about 10 days here in the u.s we've actually said those first five days
Speaker:you stay at home if you're going to go out the next five wear that tight-fitting mask
Speaker:don't go out to dinner don't do any risky behavior you might continue to be contagious but really
Speaker:it's those unvaccinated people that are most risk after those first five days so really hard with a
Speaker:pcr even really hard with an antigen test to say i'm no longer contagious because they may continue
Speaker:to be positive even after you're no longer contagious once an antigen test turns negative
Speaker:credibly unlikely that you still would be transmitting contagious for others thank you
Speaker:and i think you're going to have michael mina on to discuss a little bit more
Speaker:about testing and this whole dynamic that's right that's right that's the
Speaker:end of march and we'll go into great detail about that yes thank you um
Speaker:right and so you've partially answered this question but i'm quite interested
Speaker:in hearing the detail a little bit more um so can you talk about the difference in contagion
Speaker:from the original source COVID due to omicron and whether you believe this is a result of our
Speaker:immune response via vaccination our immune response via infection from the virus
Speaker:a viral mutation or a combination of all three so i'm kind of asking you why we've had these changes
Speaker:yeah you know the biggest reason we're continuing to have variance is every time you allow an
Speaker:individual to get infected every time you allow a person to have reproduction of the virus
Speaker:it's a roll of the dice it's another chance for the virus to stumble across an advantageous change
Speaker:so having huge numbers of the population exposed having huge numbers of people get infected
Speaker:that's going to create opportunities for change the other is really the issue of not having people
Speaker:vaccinated if you have a vaccinated population it's going to give the virus a lot less roles of
Speaker:the dice as we talked about a lot less chance for that virus a lot less time for that virus
Speaker:to create viable infectious virus with advantageous advantageous changes to go
Speaker:on to the next individual what vaccines are doing they're really shortening that period of time that
Speaker:the virus can roll the dice that the virus can potentially stumble on to another advantageous
Speaker:chain so what is creating variants a lot of it unfortunately i think is global vaccine inequity
Speaker:all these areas of the world where instead of the people having the advantages of vaccines to
Speaker:shut down that virus quicker we are seeing people get infected we're seeing people get re-infected
Speaker:and we're seeing this just tremendous pool of viruses potentially changing and finding
Speaker:some way to either transmit faster short that reproductive cycle get from one individual
Speaker:to more people in a shorter period of time or even obey the immune defenses
Speaker:yes and um to give another plug we do have uh mr david morley who's the president and ceo of unicef
Speaker:and dr anna banerjee infectious disease specialist and pediatrician coming on in a few weeks time to
Speaker:talk about global vaccine equity so yeah thank you for bringing that up and do stay tuned listeners
Speaker:um you've answered quite a lot of of my questions already thank you daniel but i have another one
Speaker:here so sars kobe 2 has been detected in cats mink and deer likely as a result of transmissions from
Speaker:humans to animal do you think there could be a mutation in these animals that's transferred
Speaker:back to humans leading to a worse variant it is certainly a concern um you know we we do
Speaker:think um getting back to the origin question that cyrus kobe 2 originally came from a non-human
Speaker:source got into the human population now we're seeing it go from humans into all these other
Speaker:animals and there is certainly the potential and there's even a discussion now was omicron from an
Speaker:individual who's immunocompromised who could not clear the virus maybe that's what or is this an
Speaker:advantageous change that developed in a mouse or some other non-human mammal and then came back to
Speaker:us so unfortunately we are seeing a lot of animals get sarskovi too develop their form of COVID 19
Speaker:this is one of those reasons why unfortunately we don't think COVID 19 is ever going to go
Speaker:away there'll always be a large percentage of people who are not vaccinated unfortunately
Speaker:there will also be all these animals that are potential reservoirs for a cross back phenomenon
Speaker:um you've already answered my question about how we can stop and prevent variants so we've covered
Speaker:a lot of ground today recognizing that you don't have a crystal ball and the virus has proven to
Speaker:evolve and adapt very quickly what does the future for this coronavirus look like in your opinion
Speaker:and any best guess on how long it could last well i i am to some degree optimistic but regionally
Speaker:optimistic it's really up to us you know what happens in the future um you know we do think
Speaker:in certain parts of the world particularly in certain areas where we have high vaccine uptake
Speaker:that at least going forward the amount of serious disease the amount of deaths and hospitalizations
Speaker:will be lower we don't expect COVID 19 to go away we do expect next winter there'd again be a number
Speaker:of cases we do expect deaths to be in the hundreds again now the big challenge for us is what happens
Speaker:globally what are we going to do and i love the plug for global vaccine equity what are we going
Speaker:to do are we going to continue to create areas where new variants can develop or are we going
Speaker:to address the inequity issues so a lot of what happens in the next year is really in our hands
Speaker:i know we're done with the virus i know we're fed up um but the virus
Speaker:is not done with us it's not fed up with us it it likes this to anthropomorphize there
Speaker:so if we're gonna have a good um winter next year it's going to really be people making
Speaker:smart decisions because we certainly can make bad decisions and set us up for more trouble in the
Speaker:future that's an excellent answer thank you our responsibility um speculating going forward will
Speaker:there be a salsa v3 or other viruses that will affect humanity to this magnitude in the future
Speaker:so yes um you know we we virologists epidemiologists infectious disease specialists
Speaker:um you know have been talking about the the risk for our population um you know
Speaker:encroaching on uh different areas where there are viruses whether animals with viruses
Speaker:we expected it to be worse we expected it to have a higher mortality when we got hit so
Speaker:unfortunately a lot of us think that this pandemic may have just been a shot over the bow
Speaker:you know two percent mortality pre-vaccines pre-therapeutics is not 10 percent it's not
Speaker:20 it's not where we saw with stars kobe 1. um it's not the plague numbers that we saw
Speaker:so no unfortunately if we don't do the right thing if we don't invest in science
Speaker:in therapeutics and technology um it's really just a question of when we have another infectious
Speaker:challenge when we have another pandemic what type of virus that will be how prepared or not
Speaker:sobering and i like the use of the term we it's been so much a situation in the past
Speaker:where illness has happened to people over there and you send some money you might go on a march
Speaker:you might even write to your local politician but you were happy in your wealthy country but
Speaker:now with the pandemic we have to think of we and everybody i think and i like the way that you've
Speaker:really stressed that no i think that that's critical and i do hope we realize that we we live
Speaker:in one world um there's no there's no borders um to the air um the whole idea that we could
Speaker:shut down air travel and somehow keep something isolated in a quarter of the world that doesn't
Speaker:work with respiratory viruses it doesn't work with something that has an incubation period where it
Speaker:could be two to 14 days from exposure to the time that you might transmit to someone else so
Speaker:i think it's really critical for our future that we embrace the fact that we're one people we live
Speaker:in one world and if we don't address that we all suffer thank you on a positive note daniel um what
Speaker:aspects of this pandemic have truly inspired you well i i am impressed um a lot of people's
Speaker:um sort of true quality have come out i mean just just to see the the sacrifices um you know we'll
Speaker:talk about the healthcare workers early on there was fear um you know we did not know healthcare
Speaker:workers did not know um how to stay safe we weren't really sure how this was transmitted
Speaker:but yet day in and day out millions of individuals were there taking care of sick to people
Speaker:holding their hands talking to them providing care particularly you know nurses all the like you know
Speaker:people who are really hands-on in there so just tremendous to to realize that even beings can
Speaker:can dig deep we really are just a compassionate caring um group of individuals so that was
Speaker:that was tremendous and the scientists you know who would have thought in a year we could have
Speaker:such effective powerful tools the vaccines you know everyone was shocked how quickly that came
Speaker:but that didn't happen overnight that was decades of people working people struggling to get funding
Speaker:people told that their ideas were crazy would never work but now we're seeing the fruits of
Speaker:of that determination and that hard work that talent and the people that believed in them
Speaker:and supported them and kept them going forward so um just really been impressive to to work
Speaker:um and to connect with so many just tremendous wonderful people over the last couple of years
Speaker:well thank you for pointing that out and i must say listeners at um and watches that uh Daniel Dr
Speaker:Daniel griffin was one of those people he's been a true inspiration i've been listening to twiv
Speaker:since near the beginning of the pandemic he now has a weekly update dedicated that's been a real
Speaker:source of knowledge for us physicians and other professionals throughout the world
Speaker:i strongly suggest that you listen to it micro tv does some amazing work and has lots of great
Speaker:channels professor Vincent Racanello even has a whole program a whole course
Speaker:on YouTube about viruses so i'm giving them an enormous plug because they enormously deserve it
Speaker:i want to thank you Daniel for joining us today and giving such a comprehensive and excellent
Speaker:overview of SARS-CoV-2 and and providing true clarity for all of us um i don't know if you
Speaker:have anything to say today anything more to say today now thank you so much for this opportunity
Speaker:thank you everyone for taking this time out of your lives to to learn and hopefully uh this is
Speaker:something that people now appreciate is really critical um that we know about that we focus on
Speaker:so we don't find ourselves in this situation again and hopefully everyone be safe be well thank you
Speaker:and please join us next week when we have Dr Daniel griffin again talking about COVID 19
Speaker:thanks for listening to this week's episode of COVID 19 the answers if you enjoyed the episode
Speaker:please subscribe rate and review and do visit our website kojalmedical.com/COVID19theanswers