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Episode 1 – Intro to SARS-CoV-2
Episode 111th February 2022 • COVID19 The Answers • Dr Funmi Okunola
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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://www.microbe.tv/twiv/

https://parasiteswithoutborders.com/

Transcripts

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Kojala Medical presents COVID 19 the answers the  show that delivers the scientific evidence-based

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knowledge that can safely return us all to our  pre-COVID lives my name is Dr Funmi Okunola and

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I'll be hosting the show every week you can listen  to me interview a highly respected professional

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about the science that can reduce your risk  of becoming infected with this coronavirus

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hello listeners and welcome to episode  1 of COVID 19The Answers. I'd like to

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introduce you all to Dr Daniel Griffin. Dr  Griffin is a physician scientist, an MD, PhD

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chief of the division of infectious  disease at pro health New York

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the senior fellow for infectious disease at united  health group and a clinical instructor of medicine

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at Columbia University's Irving Medical Center  where he is also an associate research scientist

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he is a speaker and educator who has lectured  throughout the world on global health topics

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and he is president of Parasites without Borders  and a co-host of the podcast this week in virology

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or TWIV of which i am an avid fan and is really  one of the inspirations for this podcast series

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Dr Griffin is active in the clinical care  of patients living in the New York area

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and has been particularly involved in the  care of patients suffering from COVID 19

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since the very beginning of the pandemic he's  going to talk to us today about SARS-CoV-2

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the virus that causes COVID 19. Welcome, thank  you, happy to be here. Really happy to have you

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right, so getting right down to bare basics  and the questions SARS-CoV-2 is a coronavirus

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so while the medical and scientific  community understand what a virus is

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the non-medical people likely don't know  so what is a virus and why do they exist

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now this is a great place to start  so what is a virus there's there's

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several ways to go about this you know us as  scientists have our very sophisticated answer

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um you know but then i think let's try to make it  something that's um accessible so you know most of

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us have been sick we felt not wonderful you know,  we we refer to them oh what bug am I fighting off

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and in that context there are several different  pathogens several different things out there

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that can make us sick this one of the simplest of  them is the virus the virus is an organism that

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really is a parasite it can't do everything itself  it actually has to co-opt the machinery of our

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cells to make us sick to make animals sick to make  plants sick even you know we'll talk a little bit

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maybe later about the types of viruses but this is  one of the simplest in distinction from a bacteria

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which a little more complex they can actually live  without us on their own we have the the funguses

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um which actually you know sometimes we use them  to help us brew beer maybe with wine things like

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that uh cheese and the like but sometimes  they can make us sick as well but that's

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really where viruses fit in they're they're one  of the three major things that can make us sick

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uh one of the simplest that's the virus a little  more complicated the bacteria and then even a

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little more complicated the fungus oh thank  you for that now we understand what a virus is

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what is a coronavirus and what makes it distinctly  different well now we we dive a little bit deeper

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and this is okay so the way we understand  viruses is there's really i'm going to say

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two parts to a virus there's the inside there's  the outside the inside is the genetic material

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and we really break viruses down into viruses  that have RNA as their genetic material viruses

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that have DNA as their genetic material the  coronaviruses they fall into that group where they

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use RNA as their genetic material so that's what's  inside but what's on the outside this is where

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the name comes from on the outside of that inner  package is the capsid um it's a protein capsule

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that surrounds that genetic material now some  viruses also have a lipid envelope around that

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and that lipid envelope for the coronaviruses  if you look at it under an electron microscope

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because these are incredibly tiny it actually  looks like the corona of the sun there's actually

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these spike proteins that surround that capsid  giving it this appearance giving it this name

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so the corona viruses most of us actually  have encountered them before a number of

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those common colds that plague us are common  coronaviruses in this case SARS-CoV- 2 is one of

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those coronaviruses that was not so common now i  think it's becoming common but makes us quite ill

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oh that's excellent Daniel thank you um SARS-CoV  or SARS-CoV-1 entered the public light in 2003

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with much publicity but seemed to disappear  reasonably quickly in comparison to sales copy 2.

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so how is SARS-CoV-2 different from SARS-CoV- 1  what is the genesis behind the two SARS viruses

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and why well actually you've already  answered why they have this name

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so this this is a great question and i think  there's there's a lot that we we've learned in

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the last two years we were lucky with SARS-CoV-1  um so just to start where do they come from we're

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going to get back to this again there are a lot of  these coronaviruses that are out there in nature

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they're in other animals a large number of them  are in bats some of these type of viruses are in

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camels and and little furry mammals and the like  um one of the nice things about sarsko v1 was that

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people were not contagious until they were quite  sick they would start to feel horrible they would

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end up in the hospital then they were contagious  there are small subtle changes with SARS-CoV-2

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enough to make it actually a different virus  where people start to be contagious before they

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start to get symptoms before they start to feel  ill and that's really been the achilles heel for

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us that's been the disaster SARS-CoV-2 though  it made people quite sick though there was a

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really high chance of death those people were not  contagious until they were in hospital until we

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could keep them isolated until we could stop that  transmission but as we've seen with SARS-CoV-2 as

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we've seen with people that have COVID 19 about  half of the transmission is occurring either

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before a person becomes symptomatic or while  they have no symptoms at all yes yes that's right

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ah the um the general feeling in the  community by the media and government

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seems to be portraying SARS-CoV-2 to be  the same as catching a cold or the flu

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how would you compare catching SARS-CoV-2  to the flu or a cold why isn't this the flu

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so i think that a lot of people who are vaccinated  who are healthy you know that that does change

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things but i think people have to keep that  memory it's only two years ago let's remember

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when people were getting this they were not  vaccinated we didn't have great therapeutics

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and what was happening about one in five twenty  percent of people were ending up in the hospital

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that's not the common cold that's not the  flu we're seeing about one in every 50 people

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we're dying um just here in New York we were  seeing over 2 000 deaths in a single day

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again not the common cold now here we're seeing  this latest omicron wave in a lot of parts of the

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world Canada the united states parts of Europe not  as many places in Asia or in Sub-Saharan Africa

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but areas where a lot of people are vaccinated  if a vaccinated person encounters SARS-CoV-2 to

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gets COVID 19 it often can feel like just a bad  cult but for the unvaccinated individuals we are

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still seeing a lot of hospitalizations a lot of  deaths with the omicron wave the week for which

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we have the most recent data for children here in  the us we were seeing three children dying per day

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we have seen hundreds of children  die during the omicron wave

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we actually reached a peak of over 3 000  deaths in a single day in the united states

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from omicron certainly not a mild common cold  that can kill 3 000 people in a single day

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thank you so much for reminding us of  that situation in those numbers and to

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think of the suffering of well everybody but  in particular children is truly heartbreaking

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moving on um there's been a great deal of  speculation around the origins of SARS-CoV- 2

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ranging from animal to human transition in an  animal market to a man-made virus produced in a

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lab what are the origins of SARS-CoV-2 in your  opinion yeah so i think this is one of those

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tough questions and there's unfortunately a lot  of political aspect to this um so let's focus on

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what we know let's focus on the science because  it is an important question we do want to know

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where this came from because we are concerned  that there may be future pandemics in many ways

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a lot of us are concerned this may have just been  a warning shot over the bow we may be facing worse

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pathogens worse pandemics in the future some of  the early discussions were focused on this idea

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that you could look at the virus and see clues  suggesting that it had been made in a lab made

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by human beings um you know when we've actually  looked at we're not seeing that that's true and

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a lot of the scientists who initially were quoted  have gone back and said you know when you actually

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look at it no one of the big things that people  looked at was this furin cleavage site a word that

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i used to think only virologists would use but  now it's something that's bantered over you know

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the holiday table with family initially this was  some smoking gun but we now realize almost every

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subclass of the coronaviruses have furin cleavage  sites that's nothing atypical that's nothing

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shocking we at this point have moved to where we  realized this probably came from an animal source

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perhaps from a bat interesting enough the people  who are still focused on the lab so well maybe

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that bat first went to the lab and then someone  took it home and gave it to someone else well

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no evidence actually that that happened um what  we suspect is that this is a virus that has been

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circulating in bad populations in southeast  asia at some point it got into the human

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population when we have our scientists look at  these animals when we do these animal sampling

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it looks like there are potential other  viruses that can cross over from animals so

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i do think this is an important question  not only where did this virus come from

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but also what are the viruses are out there in  nature lurking I do not think this was created by

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a scientist or any way a malicious mad scientist  attack upon humanity. Thank you for that and

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and i don't i know you're not a zoologist, but bats do contain a lot of carry around

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a lot of viruses that could be dangerous to us  but have no effect on them i think it would be

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interesting in the future and i think there  are studies looking at that because it might

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bring clues to how we could protect ourselves  uh against the immunity that they seem to have

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yeah i would agree wholeheartedly bats bats  are fascinating i actually find them quite cute

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but no they they're quite different than  us because they're so metabolically active

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they have a whole different immune system uh  they have a whole different interaction with

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viruses with illnesses um and you know i think  unless we uh really put our resources um into this

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ahead of time we're gonna end up putting a lot  of resources into this after the fact um during

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another pandemic indeed um you've answered that  question i'm not sure the public distinguishes

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between SARS-CoV-2 and COVID 19 please help us  to understand the difference between the two  ,

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yeah i i it would have been nice if we  all got together and planned the naming

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a little bit better so it's it's always  nice like with polio you have polio disease

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polio the virus um but uh in in this case um  initially the terminology was novel coronavirus

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and then it ended up getting you know named  as a disease COVID but the virus and so here's

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here's really to cut to the chase the virus that  makes us sick the name of the virus is SARS-CoV-2

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the disease the i'm sick i have the  COVID 19 so COVID 19 is the disease

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SARS-CoV- 2 is the cause of that  disease thank you for that clarity

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we toss around the word pandemic as a description  of what we have experienced in the last two years

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to help us understand the current global situation  let's start with the definition of a pandemic

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what is a pandemic okay certainly um you know  my dad always tells me like think about what

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the words mean and we can break this word down and  really pan is the big thing that helps us here pan

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is really referring to something that is involving  the whole world much of the world all around

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not just a localized epidemic so that's really  the distinction we're making an epidemic would

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be if there was a problem just in canada for  instance a pandemic is when you start involving

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many many countries when it starts to become  around the world but there's another distinction

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in here which everyone is really starting to ask  about now when does this go from not pandemic

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to epidemic but when does it go from pandemic to  endemic when do we stop having these huge surges

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that overwhelm our health care systems um when  do we stop having people show up at ERs and they

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can't get treated with a twisted ankle or having a  heart attack or you know some other horrible thing

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and that has a lot to do with getting those  numbers down and getting numbers to a predictable

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level where we have expectations um and are  able to bring resources to bear to do that we

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are thinking in many parts of the world we may be  making that last transition we don't think SARS-

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CoV-2 is ever going to be localized to just  one part of the world so the pan part but we

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do think it's going to transition from a pandemic  level to an endemic level probably settle into a

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seasonal pattern where in certain parts of the  world the times that more people are inside and

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together let's take the rainy season in certain  parts of the world let's take the winter in other

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parts of the world where people are inside we'll  be seeing higher rates then times when people are

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outdoors the dry season the summer then we'll be  seeing lower levels and a lot of this is based

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upon our understanding of how this transmits  the fact that this is a respiratory viruses

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and many of the coronaviruses with which this is  similar have settled into that seasonal pattern

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so do you think that we're at that stage now do  you think that we're at the endemic stage now

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i think we're nearing it in certain parts of the  world and i think that that's the big challenge

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for us when i say in certain parts of the world  with the latest omicron surge um here in in the

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west here in Canada and the united states actually  much through Europe as well we have a large

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percent of people now who are either vaccinated  or recently infected we have a lot of therapeutics

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on the horizon just increasing access that will  allow people should they get infected to stay out

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of the hospital again getting it below that limit  that's going to overwhelm our health care systems

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but still that inequity there's many parts  of the world where they're continuing to do

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everything they can to be safe but they don't  have that great advantage of access to vaccines

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and while that continues that puts not only those  individuals at risk but the rest of the world at

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risk at risk of more variance more challenges to  that wonderful protection that vaccines afford us

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i see so even though the rates of hospitalization  are high at the moment the death rates are high

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in places like the state you think we're moving  towards an endemic phase at this moment in time

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i i think we're moving i don't think we're  there yet i think that's really important

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we're not there yet but we are moving um i  suspect we'll get a little bit of a bump we

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have a big athletic event coming up here in the  us and whenever we have a holiday whenever we

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have a reason for a bunch of people to be all  gathered together we see a little bit of a rise

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but we are heading towards warmer weather we're  expecting numbers to come down for a while but

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we do expect numbers to rise again next fall and  when they do rise instead of people ending up in

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the hospital some people will be able to stay  out because they've been vaccinated some people

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will also stay out because they'll have access  to medications therapeutics that keep them out

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you know hopefully as we move forward those  numbers will keep moving in in the right

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direction so i see where you're coming from  and how there's the difference so basically if

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you're in a rich western country well-resourced  country that has access to vaccines readily

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treatments readily you can you feel that there can  be an exercise on the control of of of the virus

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we can somehow minimize the outbreaks or possibly  even eliminate them if we have a high enough

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proportion of the population vaccinated i'm am i  correcting in as painful as it is the way you word

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that you're worrying it correctly um in privileged  parts of the world where we have the ability to

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vaccinate not only once but twice but now  three times certain higher risk people maybe

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even a fourth vaccine where we have access to  therapeutics that might be six or eight hundred

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dollars or even two thousand dollars for a course  talking about the antivirals and the monoclonals

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it's a much different situation than some parts  of the world where less than one percent of

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the population has access to vaccines where  those expensive therapeutics are out of reach

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so really a lot of inequity here that  we really need to address thank you for

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that clarification excellent answer really um  we've had three pandemics in the last 20 years

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HIV aids which is ongoing from the 1980s and i  know as a research specialist research area for

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yourself H1N1 swine flu influenza in 2009 and now  COVID 19. how are these pandemics different from

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the 1918 to 1920 Spanish flu or the bubonic plague  of the 14th century that have occurred previously

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all right so we're going to need a whole podcast  for just that question but let's go into it

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sorry no no this is for and i really  appreciate that you bring this up

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let's start with HIV aids um it's really tough  i still remember seeing a movie surviving the

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pandemic and i was quite shocked because  this pandemic that pandemic it is not over

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there are over 30 million people in the world  living with hiv in the united states we have

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over a million people living with hiv this  is not a pandemic that we've gotten through

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we continue to see large numbers of people getting  infected every year we continue to see hundreds

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of thousands of deaths so we are still in that  pandemic what was really tough about that pandemic

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was this us them view this idea that this was  not our pandemic that it was a pandemic of

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other people that somehow it was those people's  fault i think that was an incredible challenge

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I personally grew up in Greenwich village  my mother was very involved with activism

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uh worked with some of the act up activists  work with a young Anthony Fauci at that point

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um so very personally still very troubling  to me that that people don't remember that

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people don't realize that this is an ongoing  challenge so thank you for bringing that up

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those were some of the differences  right it was not a respiratory pathogen

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it was not embraced as our problem as a global  community hopefully that is improving now let's

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move to influenza that was slightly different  and actually has a lot of similarities here right

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respiratory virus it was actually not just um  focusing on elderly but we're actually seeing

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younger individuals dying at higher rates  than we were used to with uh prior influences

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this is something also that got to the point  where it was stressing but not overwhelming our

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healthcare systems but what did we have lots of  experience with vaccines we had therapeutics it

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was a disease that we were familiar with not  as frightened by we understood transmission

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a lot of big differences when we ran  into COVID 19 there was a lot of fear

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there was a lot of panic and there still is  people throwing different therapies at it

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just hoping wanting to believe desperately  that they could make a difference really

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quite a difference and going back to the 1918 well  that's kind of very similar to what we experienced

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and are still experiencing a lot of fear there  were no vaccines there were no therapeutics

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not even quite sure about how it was being  transmitted there were there were masks there

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were even anti-mass protests there were really a  lot of similarities and actually we're seeing sort

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of the tail end similarities people talk about  how that uh influenza pandemic ended but people

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continued to die when people had just finally  reached a point where they were exhausted they

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no longer wanted to hear or read about it or take  any more measures so unfortunately i think we're

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we're reaching that social exhaustion phase here  while COVID 19 in the US is still on some days

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killing over 2 000 individuals wow wow and i guess  with the bubonic plague the numbers were just

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phenomenal i think the numbers of deaths i think  they went into the hundreds of millions wasn't

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yeah i mean the bubonic plague overwhelming  in many ways um just because the mortality

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was so high i mean some estimate a third  of people in Europe died but then again

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we had bubonic plague in china while the west was  busy fighting world war one the chinese asked for

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assistance we couldn't offer any because we were  busy doing what we were doing so bubonic plague is

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you know we always hear about it think about it  and focus on europe but this was a global issue

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well i didn't realize that about china and thank  you again for another excellent answer um okay

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we now understand what a pandemic is and how the  current pandemic is different from past pandemics

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at the initial stage of the pandemic there was  so much unknown about the transmissibility of

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the virus and public health initiatives were  inconsistent and often lacking specific direction

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we now know more about the virus with that in  mind in your opinion how is sales cov2 transmitted

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so i think one of the biggest challenges and  one of the things i hope we learned from this

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pandemic is the importance of of communication say  science communication public health communication

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this is a respiratory virus you  don't get this by surfaces it's

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very uncommon that it's spread by surfaces  you don't get this by swimming in a pool

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you get this bite breathing you get this this  is a respiratory virus and you acquire it by

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exposure to your respiratory system um breathing  it into your nose breathing it into your mouth

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so i i love the there was an article by roxanne  comcy where she says it may not be airborne but

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it's borne by the air this distinction of  airborne is is a very confusing scientific

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in-hospital infection control distinction  that just did nothing but muddy the waters

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if you are a little bit away you decrease your  risk to some degree you get a little farther away

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that's better but once you get in a closed indoor  situation nowhere's safe it's circulating around

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most of our transmission we realize probably is  occurring in these indoor settings because what do

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people do indoors they breathe there isn't great  ventilation there isn't great dilution effects

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um so yeah this is a respiratory virus i do want  people to keep washing their hands but to be

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honest it's the breathing air particularly in a  closed indoor space with someone who is infected

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someone who is letting the virus out we do know  that really really high concentrations are in

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your nose so when we're asking people to mask if  you're not covering your nose you're not wearing

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a mask very excellent point um and i do see the  25 percent of people wearing their masks under

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their nose so thank you for making that that  point um and also we uh we have professor uh

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jiminez coming uh on uh later on in the series  to talk all about uh uh saskov to uh in the air

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oh that is fantastic um and white i'm just getting  to the at the start of the pandemic um the r

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naught for ancestral sarsko v2 was two to three  versus the highly contagious measles at 15 to 18.

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today with omicron the virus is rated second only  to measles in terms of contagion with an r naught

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of 8 to 15. in simple terms how would you explain  r naught and rt the transmissibility measurement

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okay so this is i think really important and you  know maybe another silver lining of the pandemic

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is everyone is interested in learning these things  um so r is just short for reproductive number and

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really if a person one person has the infection on  average how many other people do they spread it to

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but it gets a little complicated so we'll go into  that the r naught is when you know nothing and

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do nothing so it's no mitigation no masks no  medicine no vaccine so are not is what is the

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average from one person how much are they going  to spread without any mitigation so that or not

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is only going to exist early on in wuhan china  before we figure out anything about the virus

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r sub t is what is going on at this specific point  in time and these are hard to calculate because

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one thing we haven't really talked about is the  reproductive time the time of that reproductive

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cycle so let's take the original wuhan ancestral  strain original estimates before we knew what

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was going on was that on average one person would  infect two to three other people so that was the

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r naught the reproductive number then on average  those three people would each infect another three

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people you're up to nine before you know it the  reproductive time was about seven days from the

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time that first person was exposed to the time  they could spread it to the next group of people

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what we've seen and a huge issue with omicron is  with each new variant that reproductive time has

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diminished so if you start asking in the original  ancestral strain in about a week one person would

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on average spread it to three people but now we're  seeing that with omicron that reproductive time

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has dropped to probably only about three days  maybe three to four so in that one week it's

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had a chance to have two reproductive cycles so  even if you still stuck with that original three

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now it's had a chance to do that twice  you're up to nine from a single individual

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in just a matter of a week so the rt per week  can appear to be tripled um one of the challenges

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um is that we are seeing over time the shortening  of that reproductive time that r sub t can be

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changed can be challenged by vaccines we can  reduce it with masking and a lot of other measures

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that was fantastic you've i'm learning so  much in this program too that's the clearest

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answer i have ever had thank you daniel um there  are three different phases of contagiousness with

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this coronavirus talk about one asymptomatic two  pre-symptomatic and three symptomatic transmission

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okay so the easiest is to break out the  pre-symptomatic from the symptomatic and

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this is really distinct from the asymptomatic some  people never ever get symptoms but those people

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as we know can still transmit the viruses so let's  let's let's go there for starters an individual

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gets exposed there's a certain incubation time  where they've been exposed but they don't have

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enough virus to spread to another individual as  mentioned early on that was about seven days with

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omicron it may only be three to four then the  person reaches a point where they never know it

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they never have symptoms but they have enough  virus that they can spread it to someone else

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that would be our asymptomatic transmission now  the other and this is a challenge for us as well

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is before you start getting symptoms SARA-CoV-2  can already be at a high enough level that one to

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two days before you feel bad if you're eventually  going to feel bad you can already be spreading it

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to other people this could be that period of  asymptomatic transmission because you don't

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feel bad you might be going to school you might be  going to the office you might be going to that big

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birthday party for your 90 year old grandmother  and so what we now know is that about 50 of the

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transmission is occurring in those asymptomatic  individuals and those pre-symptomatic individuals

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that still leaves a chunk about 50 percent  of transmission people starting to feel bad

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that first day or two maybe probably out to day  five but really diminishing out to day ten when

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you're not feeling well you're coughing you're  sneezing and you again can transmit SAR SCoV 1

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only was transmitted during that when i feel sick  phase influenza again really not much transmission

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until you feel sick so really this asymptomatic  pre-symptomatic i feel fine but can still spread

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it to others that has really been a disaster  and a challenge for us with COVID 19. thank you

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shifting gears let's move to discussing variants  the virus appears to be evolving we started with

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the original or ancestral strain of sarsko v2 from  wuhan there have been many variants but several

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variants of concern from alpha beta gamma  delta to now omicron please help us understand

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what is a variant and how is  this different from a mutation

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okay well one thing i'll say i think  this is really important and this is

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humility all across the board for scientists  we initially looked at coronaviruses and

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said this is a fairly stable virus we're not  expecting changes we're not expecting variants

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early on it was spreading there were maybe  seven changes seen throughout the entire world

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we thought we we had this beat and then we  started to see these changes so let's let's

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go back to what we all learned about with viruses  this is a virus the genetic material inside is rna

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that rna every three bases of that rna codes for  a certain amino acid those amino acids are going

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to build those proteins and those are proteins  that we're all familiar with the spike protein

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the nucleocapsid right that's  that structural protein around

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the rna polymerase the one that actually  we're targeting with some of our drugs now

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what we have seen over time is there is  a certain amount of pressure selection

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pressure on a random background of changes where  a change is actually advantageous for that virus

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as we talked about one of the advantages might be  that instead of it taking seven days to go from

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one person to the next it might only take five or  four or down to maybe three so we start off with

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changes in the rna that result in changes in the  amino acids that result in changes in that protein

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if the rna changes and you can have changes  that are silent that don't change the protein

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we really don't see them we don't care about them  mutations are in the rna amino acid changes we

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call mutations we probably shouldn't we upset our  scientific colleagues but changes in those amino

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acids people have come to call those mutations  that's when we start seeing antibody evasion when

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we start seeing viruses that can't be neutralized  if you recently were infected by delta as we saw

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when omicron came on the scene so the initial  variance of interest we noticed some changes

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variance of concern when those changes were  significant to really change the biology to

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change the fitness of the virus to either allow  it to have a shorter reproductive time allow it

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to have the ability to evade immunity whether  it's vaccine or prior infections thank you

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why i think you've already answered this um  partially this question so um i think you've

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already answered why saskov2 develops variants  do you have any sense of what potential future

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variants could be you know we we are concerned  that there will continue to be variants um because

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one is we do realize that coronaviruses change  over time and it isn't just sars kobe 2. we've

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really started to look more closely at the  other coronaviruses and they change over time

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the preliminaries it makes errors you end up with  a copy of the rna that's a little bit different

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and sometimes that little bit  different can be helpful so

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what are what are the big drivers now we're  seeing a sub-variant of omicron where again

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slightly shorter reproductive time right  so to go from one person to the next

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maybe even a little quicker than we saw  with omicron so that's one bit of pressure

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the other big pressure that we saw with omicron is  the ability to reinfect people who were infected

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before and also the ability to infect people who  were vaccinated but not boosted to try to get

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around that so we call immune evasion there really  isn't a lot of selective pressure to make people

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sicker it's all about the virus becoming fitter  the virus being able to out-compete other variants

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the virus being able to get into those  respiratory niches and make people sick

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this is such a rich conversation and you know  we're so privileged to have a person such as

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yourself with such specialist knowledge being part  of this program really would like to thank you um

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so the scientific community identifies  variants by genomic sequencing

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what is genomic sequencing and how has it been  applied in this pandemic so the timing of this

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question is perfect because we are celebrating  50 years since the discovery of the reverse

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transcriptase so what do we do we take  the rna and we use this enzyme that was

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discovered in david baltimore's lab  youngest nobel prize winner i think

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and what you do is you copy that rna to dna and  we were able to read the sequence of the dna which

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corresponds to that original rna really sort  of a photographic negative of the rna sequence

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so around the world thousands of labs millions of  sequences have been generated we take one of those

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samples people are now familiar with either  the front of the nose maybe the brain biopsy

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sample that beautiful test that we do that sample  then goes off that genetic material that rna is

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isolated it's reverse transcribed to dna and then  we read the sequence with our sequencing machines

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these go into these huge databases where they're  being analyzed some parts of the world do a

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tremendous job of generating lots of sequences  getting them into these big databases and

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tracking it so that's genomic we are we are  sequencing the genome of this rna virus thank you

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the length of time from infection to a person  being contagious appears to have changed with

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omicron as you cited a couple of weeks  ago on twitter how long does it take for

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a human being to become contagious with  sales coverage ii when first infected now

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yeah i mean unfortunately now we're seeing and  i've touched on this a few times it may only be as

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little as three days with the ancestral wuhan um  variant we were seeing probably about seven days

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um you know maybe people were a little bit you  know contagious a little bit before that day seven

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but really about seven days between one person and  the next with alpha it dropped a little with delta

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it dropped more and then we're down to three  to four from omicron we first started noticing

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this with well right after a very interesting um  ritual celebration event we have here in new york

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city called santacon where apparently people  dress up as santa claus and go from bar to bar

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this occurred on a saturday night we started  seeing positives as early as monday and tuesday

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really alerting us that something was different  about the reproductive cycle time with omicron so

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really very quickly people were getting exposed  within two to three days we were starting to

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see positive tests appear i've also read some  research whereby people get symptoms with omicron

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are using the rapid antigen tests which show  up as being negative and then several days um

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sometimes when the symptoms are sort of  easing they're they're testing positive

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and this seems to have happened with omicron can  you um provide some light on that yeah so i think

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this this is excellent this will be our public  service for people to think about how to use those

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tests properly um we had a lot of ideas on this um  you know early on we talked about how people would

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be positive for a day or two before symptom onset  but now we started to see that people were getting

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symptoms and then not getting that positive test  until the next day early on with the ancestral

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strain we had higher levels just right before  symptoms occurred than when symptoms started to

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occur when symptoms occurred it was already on the  way down recent challenge study in the uk looking

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at this we had hoped that oh it's because people  are vaccinated it's because their immune system

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is ramping up maybe it's prior infection but that  recent data really confirms that this this dynamic

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the first day that you start to feel crummy is not  the best time to go ahead and do that test give it

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a day see how you're doing it's that second day  when you're going to have the best sensitivity

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for those rapid tests so we have a challenge  in our pediatric offices right mom brings in

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johnny johnny started to feel bad last night and  now mom wants to know can he go to school the

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answer is no the answer is we do a test right away  even if that's negative we're going to send off a

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pcr or we're going to retest the next day when  we have our sensitivity so um don't don't think

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that one test predicts the future think about the  timing of when the best time to do that test is

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and it's really after a full 24 hours of symptom  onset okay are we also seeing with omicron that

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people are contagious for a longer period of time  even if if vaccinated um i read somewhere that um

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from a few specialists on twitter that that  we can have a situation whereby when you're

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vaccinated where you can be contagious for  up to maybe nine ten days and if you're

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unvaccinated possibly up to 20 days um have  you do you feel there's any relevance in that

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so i don't think it's true and i'll tell you  why and i think it's great that this comes up

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one of the things that hopefully and maybe people  listen to twiv after this one of the things we

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always try to talk about is the difference  between rna and viable contagious infectious

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virus so if an individual is vaccinated and  they get exposed and they get infected they

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can still have really high levels of rna they can  still have significant levels of infectious virus

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but what we're seeing is that rna comes down  quicker in someone who's been vaccinated than

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someone who's not and we also see the resolution  of infectious viable virus coming down much

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quicker so i know people are still getting  positive antigen tests they're still getting pcrs

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well out but they're ceasing to  have infectious transmissible virus

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it vaccinated probably after about five days  unvaccinated probably after about nine or ten days

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okay so that makes it very difficult to interpret  an antigen test in those scenarios it's really

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hard to interpret an antigen test to try to end  your quarantine so if you start to feel sick

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and your antigen test is positive for five  days you're probably infectious we recommend

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being careful for about 10 days here in the  u.s we've actually said those first five days

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you stay at home if you're going to go out  the next five wear that tight-fitting mask

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don't go out to dinner don't do any risky behavior  you might continue to be contagious but really

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it's those unvaccinated people that are most risk  after those first five days so really hard with a

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pcr even really hard with an antigen test to say  i'm no longer contagious because they may continue

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to be positive even after you're no longer  contagious once an antigen test turns negative

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credibly unlikely that you still would be  transmitting contagious for others thank you

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and i think you're going to have michael  mina on to discuss a little bit more

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about testing and this whole dynamic  that's right that's right that's the

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end of march and we'll go into great  detail about that yes thank you um

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right and so you've partially answered  this question but i'm quite interested

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in hearing the detail a little bit more um so  can you talk about the difference in contagion

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from the original source COVID due to omicron  and whether you believe this is a result of our

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immune response via vaccination our immune  response via infection from the virus

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a viral mutation or a combination of all three so  i'm kind of asking you why we've had these changes

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yeah you know the biggest reason we're continuing  to have variance is every time you allow an

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individual to get infected every time you allow  a person to have reproduction of the virus

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it's a roll of the dice it's another chance for  the virus to stumble across an advantageous change

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so having huge numbers of the population exposed  having huge numbers of people get infected

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that's going to create opportunities for change  the other is really the issue of not having people

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vaccinated if you have a vaccinated population  it's going to give the virus a lot less roles of

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the dice as we talked about a lot less chance  for that virus a lot less time for that virus

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to create viable infectious virus with  advantageous advantageous changes to go

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on to the next individual what vaccines are doing  they're really shortening that period of time that

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the virus can roll the dice that the virus can  potentially stumble on to another advantageous

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chain so what is creating variants a lot of it  unfortunately i think is global vaccine inequity

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all these areas of the world where instead of  the people having the advantages of vaccines to

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shut down that virus quicker we are seeing people  get infected we're seeing people get re-infected

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and we're seeing this just tremendous pool  of viruses potentially changing and finding

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some way to either transmit faster short that  reproductive cycle get from one individual

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to more people in a shorter period of  time or even obey the immune defenses

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yes and um to give another plug we do have uh mr  david morley who's the president and ceo of unicef

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and dr anna banerjee infectious disease specialist  and pediatrician coming on in a few weeks time to

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talk about global vaccine equity so yeah thank you  for bringing that up and do stay tuned listeners

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um you've answered quite a lot of of my questions  already thank you daniel but i have another one

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here so sars kobe 2 has been detected in cats mink  and deer likely as a result of transmissions from

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humans to animal do you think there could be  a mutation in these animals that's transferred

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back to humans leading to a worse variant it  is certainly a concern um you know we we do

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think um getting back to the origin question that  cyrus kobe 2 originally came from a non-human

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source got into the human population now we're  seeing it go from humans into all these other

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animals and there is certainly the potential and  there's even a discussion now was omicron from an

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individual who's immunocompromised who could not  clear the virus maybe that's what or is this an

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advantageous change that developed in a mouse or  some other non-human mammal and then came back to

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us so unfortunately we are seeing a lot of animals  get sarskovi too develop their form of COVID 19

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this is one of those reasons why unfortunately  we don't think COVID 19 is ever going to go

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away there'll always be a large percentage of  people who are not vaccinated unfortunately

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there will also be all these animals that are  potential reservoirs for a cross back phenomenon

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um you've already answered my question about how  we can stop and prevent variants so we've covered

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a lot of ground today recognizing that you don't  have a crystal ball and the virus has proven to

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evolve and adapt very quickly what does the future  for this coronavirus look like in your opinion

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and any best guess on how long it could last well  i i am to some degree optimistic but regionally

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optimistic it's really up to us you know what  happens in the future um you know we do think

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in certain parts of the world particularly in  certain areas where we have high vaccine uptake

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that at least going forward the amount of serious  disease the amount of deaths and hospitalizations

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will be lower we don't expect COVID 19 to go away  we do expect next winter there'd again be a number

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of cases we do expect deaths to be in the hundreds  again now the big challenge for us is what happens

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globally what are we going to do and i love the  plug for global vaccine equity what are we going

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to do are we going to continue to create areas  where new variants can develop or are we going

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to address the inequity issues so a lot of what  happens in the next year is really in our hands

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i know we're done with the virus i  know we're fed up um but the virus

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is not done with us it's not fed up with us  it it likes this to anthropomorphize there

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so if we're gonna have a good um winter next  year it's going to really be people making

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smart decisions because we certainly can make bad  decisions and set us up for more trouble in the

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future that's an excellent answer thank you our  responsibility um speculating going forward will

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there be a salsa v3 or other viruses that will  affect humanity to this magnitude in the future

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so yes um you know we we virologists  epidemiologists infectious disease specialists

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um you know have been talking about the  the risk for our population um you know

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encroaching on uh different areas where there  are viruses whether animals with viruses

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we expected it to be worse we expected it to  have a higher mortality when we got hit so

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unfortunately a lot of us think that this  pandemic may have just been a shot over the bow

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you know two percent mortality pre-vaccines  pre-therapeutics is not 10 percent it's not

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20 it's not where we saw with stars kobe 1.  um it's not the plague numbers that we saw

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so no unfortunately if we don't do the  right thing if we don't invest in science

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in therapeutics and technology um it's really  just a question of when we have another infectious

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challenge when we have another pandemic what  type of virus that will be how prepared or not

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sobering and i like the use of the term we  it's been so much a situation in the past

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where illness has happened to people over there  and you send some money you might go on a march

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you might even write to your local politician  but you were happy in your wealthy country but

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now with the pandemic we have to think of we and  everybody i think and i like the way that you've

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really stressed that no i think that that's  critical and i do hope we realize that we we live

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in one world um there's no there's no borders  um to the air um the whole idea that we could

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shut down air travel and somehow keep something  isolated in a quarter of the world that doesn't

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work with respiratory viruses it doesn't work with  something that has an incubation period where it

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could be two to 14 days from exposure to the  time that you might transmit to someone else so

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i think it's really critical for our future that  we embrace the fact that we're one people we live

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in one world and if we don't address that we all  suffer thank you on a positive note daniel um what

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aspects of this pandemic have truly inspired  you well i i am impressed um a lot of people's

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um sort of true quality have come out i mean just  just to see the the sacrifices um you know we'll

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talk about the healthcare workers early on there  was fear um you know we did not know healthcare

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workers did not know um how to stay safe we  weren't really sure how this was transmitted

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but yet day in and day out millions of individuals  were there taking care of sick to people

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holding their hands talking to them providing care  particularly you know nurses all the like you know

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people who are really hands-on in there so just  tremendous to to realize that even beings can

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can dig deep we really are just a compassionate  caring um group of individuals so that was

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that was tremendous and the scientists you know  who would have thought in a year we could have

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such effective powerful tools the vaccines you  know everyone was shocked how quickly that came

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but that didn't happen overnight that was decades  of people working people struggling to get funding

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people told that their ideas were crazy would  never work but now we're seeing the fruits of

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of that determination and that hard work that  talent and the people that believed in them

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and supported them and kept them going forward  so um just really been impressive to to work

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um and to connect with so many just tremendous  wonderful people over the last couple of years

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well thank you for pointing that out and i must  say listeners at um and watches that uh Daniel Dr

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Daniel griffin was one of those people he's been  a true inspiration i've been listening to twiv

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since near the beginning of the pandemic he now  has a weekly update dedicated that's been a real

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source of knowledge for us physicians and  other professionals throughout the world

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i strongly suggest that you listen to it micro  tv does some amazing work and has lots of great

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channels professor Vincent Racanello  even has a whole program a whole course

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on YouTube about viruses so i'm giving them an  enormous plug because they enormously deserve it

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i want to thank you Daniel for joining us today  and giving such a comprehensive and excellent

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overview of SARS-CoV-2 and and providing true  clarity for all of us um i don't know if you

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have anything to say today anything more to say  today now thank you so much for this opportunity

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thank you everyone for taking this time out of  your lives to to learn and hopefully uh this is

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something that people now appreciate is really  critical um that we know about that we focus on

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so we don't find ourselves in this situation again  and hopefully everyone be safe be well thank you

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and please join us next week when we have Dr  Daniel griffin again talking about COVID 19

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thanks for listening to this week's episode of  COVID 19 the answers if you enjoyed the episode

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please subscribe rate and review and do visit  our website kojalmedical.com/COVID19theanswers

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