Virus isolates, variants, strains - what are they?

Many virology terms are being used these days by people who do not understand their meaning. Included are journalists, medical doctors, scientists, lawyers, and people from all walks of life. In normal times this word mis-usage would be so rare that it would not matter. However, because we are in a viral pandemic that affects nearly everyone, I will attempt to explain the meaning of virus isolates, variants, and strains.
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[@tippytops4121]

Your philosophy of free education is refreshing and welcome in a world where such noble integrity is rare. Thankyou.

[@DawnLevendula]

I agree!

[@thierryfucus8697]

@@DawnLevendula We truly thank all heroes that are helping end this pandemic. # Stay SAFE

[@Stefan-gh7xr]

@IfWhiningAtProblemsWorks, WhyDoCorporationsLobby? Jup, indeed. Only that refutes everything

[@Stefan-gh7xr]

@IfWhiningAtProblemsWorks, WhyDoCorporationsLobby? Just send me one scientific paper where a virus is isolated and purified. I will wait 🤡

[@Stefan-gh7xr]

@IfWhiningAtProblemsWorks, WhyDoCorporationsLobby? ah sorry :). Well, what I meant with "only that" is that the lack of proof of natural contagion is already sufficient to disprove virology. And there are so many more reasons 😉

[@mindbodyspirfit]

I left this comment for him : "This was interesting and helpful in understanding how the terms are used in virology. What I notice at once is that the term "isolate" in virology has a different meaning than in any other venue. The sequence shown in that slide doesn't show any virus being taken out of the swab sample. The entire sample, along with the liquid it's dissolved in, is put in the lab dish with the cells. So when the cells die and beak down, how do you know that it was something in the patient sample that killed them, since you didn't do a control where everything EXCEPT the patient sample was used? And, how do you know it was a virus in the patient sample, since there are many other elements in there: human cells and mucus, bacteria, fungi, toxic substances that might have been breathed in and caught in the patient's mucus. So why is it called "isolate" when there was no point at which ONLY the virus was used?"

[@vickiezaccardo1711]

And just exactly how did they get a sequence if the sample was never isolated and purified?

[@saragct1]

Because its a cock and bull story. Catch hold of one unicornologist sorry virologist and ask him these critical questions. Watch him run away without answers.

[@SoulStay]

So question about isolates. You said you take the nasal swab, put it in a tube with some liquid, and put some of the liquid into a culture dish with some cells already growing and grow it; and that's isolation. If a person has 2 different virus, or a bacteria and a virus in their nose, how would growing them in a dish isolate them? It's my understanding isolate means to set apart from all others; or in the case of people, to quarantine or isolate someone in solitary confinement. A separation from everything else. How would this test accomplish that if the sample being put into the dish was never isolated? Bad in, bad out right? I've seen labs selling "isolated" virus, when they state the sample contains largely human and cow proteins. You also said there is no definitive definition. How is that scientific?

[@Ruby-ev7wm]

This was interesting and helpful in understanding how the terms are used in virology. What I notice at once is that the term "isolate" in virology has a different meaning than in any other venue. The sequence shown in that slide doesn't show any virus being taken out of the swab sample. The entire sample, along with the liquid it's dissolved in, is put in the lab dish with the cells. So when the cells die and beak down, how do you know that it was something in the patient sample that killed them, since you didn't do a control where everything EXCEPT the patient sample was used? And, how do you know it was a virus in the patient sample, since there are many other elements in there: human cells and mucus, bacteria, fungi, toxic substances that might have been breathed in and caught in the patient's mucus. So why is it called "isolate" when there was no point at which ONLY the virus was used?

[@BioLogicalNerd]

The way you think we can just pluck a virus or bacteria from a swab with a tweezer is cute yet enraging at the same time.

[@jaboris2536]

Biggest lie in history Is saying viruses are not a different variation of exomeres that accumulate as a last resort for waste removal. Right next to UFOs aren’t real

[@victorc4518]

I suggest you research the process of isolating bacteria in agar dishes. It's a similar process for bacteria; however, it's much harder to isolate a virus since changes in a dish often won't be obvious.

[@jaboris2536]

@@victorc4518 this is such pseudoscience that’s passed on for replicable data. There is more evidence that viral structures are secreted from our OWN CELLS as a last ditch effort to remove toxilogical content in the system. The piteee dish could be contaminated instantly wouldint it? Wouldn’t you already see “variants” forming after hours? How do you isolate a virus? Show the mechanisms. None of your science is replicable and virology is a money making scheme. The human body has thousands of its own viruses. You are being lied to big time.

[@jaboris2536]

@@victorc4518 Bactria has nothing to do with viruses they are extremely different sizes you muppet

[@roberteastwood6937]

But how do you isolate the "sample" from the snot? You did not mention centrifuging. Is that not necessary? Isn't the snot full of all kinds of stuff?

[@jeffrunge6427]

You're not crazy xD this man literally said "and in the laboratory you take a little bit of that fluid and you ADD it to the culture dish and THAT is how you isolate a virus." xD oh lordy. Blows my mind how non-existent the pushback is from this comment section xD

[@victorc4518]

@@jeffrunge6427 He simplified it...what he said was an accurate, but oversimplified overview. As someone who worked in a lab before, explaining exactly how one isoaltes a virus would be a full video series in itself.

[@mrwilliamz311]

@@victorc4518 Cool. And what say you to people who say viruses don’t exist and/or they’re exosomes? It is said that growing viruses in vero monkey cell culture is problematic because the cells produce exosomes…

[@victorc4518]

@@mrwilliamz311 I won’t speak on something I haven’t read up on/have no experience in. However, viruses most definitely exist…

[@stompthedragon4010]

Exactly. He isolated some snot and called it a virus.

[@beedleChompz44]

The book Virus Mania is contrary to many ideas presented here. I would love to hear your side and defend virology against a book like Virus Mania. Thank you so much for your efforts!

[@BioLogicalNerd]

The author behind the book is in the realm for microbiology+virology that we hold flat earthers.

[@msheart2]

@@BioLogicalNerd lol, oh there it is, a shills typical response, flat earth.

[@anythreeletters]

@@msheart2 The book in question says that viruses aren't real. This is indeed within the same realm as flat earth stuff.

[@jan-martinulvag1953]

Can you give an example of someone taking a virus from on organism and making another organism sick from it?

[@anythreeletters]

This is done routinely. LCMV is one such example. Vaccinia virus strain western reserve is another. HIV yet another example.

[@karl9460]

Wow, as someone who was not trained to understand I can tell you that I understood perfectly. Fantastic.

[@VilhelmKruse]

I would love to undersand the topic of 'isolating a virus'. At 3:16 you explain the sequence of the creation of the isolate. It seems to me that all kinds of stuff is grown in the petri dish (step 3). I fail to see how the growth in the petri dish can be referred to as something that is isolated from something else... What am I missing?

[@yannick4014]

That's the deception of virology. They use language that not only deceives the general public but also themselves. Not one human being has ever isolated a virus in it's full form and separated it from all other cellular/biological contaminants and sequenced that genome in its entirety. Look up Dr Stefan Lanka. He has recently conducted the control experiments using 2 independent labs for "sars-cov-2" which show that the cytopathic effects in these cultures are in fact a direct result of the technique i.e. the experiment itself and not by so called infected material. Virologists have been deceiving themselves for decades. It was known back in 1954 when they did control experiments for Measles that there was no distinction between the cultures with infected and non infected material. Every single virus genome is a computer generated model.

[@dallysinghson5569]

wtf??? we do have isolates of the virus!! have you not been listening? the way virologists use languge is not a deception, its on you for not realising that we reuse terms in slightly different ways because reinventing whole new terms you have something already pretty close is stupid

[@dallysinghson5569]

It's as close as you practically can to getting "isolation". Take for example some crazed individual amputates somebodies arm... Person A) He's just isolated the man's arm from his body! Person B) I fail to see how, there's still blood in the arm, air surrounds it and all, it needs to be clean and in a vaccum! These are meaningless arguments. Viruses ARE TINY. You can have a solution of them but you'd then argue being in a solution means its not just viruses therefore not isolated. You want PURE viruses? You'll get nothing because how will you pick up the virus and move it about? They're so insanely small you'll need factories the size of the planet to have a sufficient quantity of them to grab with your hand and then it'ld still be a lump of "nothing" to you.

[@yannick4014]

@@dallysinghson5569 It absolutely is deceptive. Please explain how a virologist 'isolates' a so called 'viral' particle in a cell culture? Explain how you can take an apparently 'infected' bit of material e.g. lung fluid. Not use the technique of filtration and gradient density ultra centrifugation to separate all other genetic material and creating a pure sample. Why is that not done? Why is the sample taken in its unpurifed state and added to a concoction of starved vero cells, mixed with antibiotics, antifungals and bovine serum? After that is done they watch for cytopathic effects WITHOUT doing a control study. To find out whether the cytopathic effects are a result of starving the vero cells, the antibiotics or antifungals etc. That these are the cause of those cytopathic effects. Then take this unpurified sample, after no control experiments have been done, then do genetic sequencing on this unpurified, unisolated sample. Sars-Cov-2 does not exist except inside of a computer simulation. Luckily Dr Stefan Lanka has gone to two independent labs and done the control experiments and is working on getting these findings published. You can watch that here - odysee.com/@DeansDanes:1/cpe-english:f So yeah, virologists don't understand what the word 'isolation' means and is nowhere near close to the original meaning. You have been deceived.

[@Jenfromtheblock59]

@@dallysinghson5569 You need to do your research, NO LIVE SAMPLE OF THE VIRUS HAS EVER BEEN FOUND. FACT!.

[@stevemotoq1411]

Virologist for 40 years, it shows in your brilliant teaching style.. love your way of taking a potshot at your own profession. Brill

[@ShiYuMeng2]

SARS-COV-2 has never been isolated (per the dictionary definition of the word which means to separate from all other things). Scientist separate very small things such as bacteriophages and exosomes routinely using ultra centrifugation, ultra filtration, and chromatography. Yet, in 150 years of virology, never once has anyone been able to actually isolate (purify & seperate) viruses.

[@anythreeletters]

You lie. I purify viruses regularly by those same methods.

[@sithwolf8017]

Pffft hahahaHAHAHA!! Hey bonehead what's a bacteriophage? A virus that targets bacteria!

[@HubertHeller]

Thank you for clearing up these terms, which are vital to understanding the subject.

[@smlorrin]

Thank you so much for taking the time to share this with us!

[@aboutmyfathersbusiness8324]

The term "Isolates" should not be used. Some call this genetic material Tags. Tags are found in different species, they are not unique. These Tags are extended and placed into a computer which fills in gaps and produces an "In-Silico" genome aka a "made up" genome which can be labeled whatever you want. Viruses are not alive nor have they ever been isolated.

[@pilardiaz2844]

Thank you Vincent. Thank for using science to bring clarity in these disturbing times.

[@LazYevgen]

Tnx for this. Any chance to explain PURIFICATION? And whether it was done ANYWHERE?

[@krishnendub1010]

Very cool, Vincent! Thank you for all your efforts.

[@luisfernando-mm3jt]

Love all your passion been following you since 2017.. Please keep up the good work

[@idabl]

Brilliant, Vincent, as ever. Thank you so much for your limitless dedication to public education of virology.

[@lakeratatouille]

Variants, isolate, strain. Viruses suffering from an identity crisis

[@thomasbarchen]

I'm laughing!

[@DeElSendero]

Great lecture Dr Vincent! Thank you very much!

[@amandapeterson3659]

Okay, so you never purified it and thus NEVER truly isolated it !

[@Miata822]

Hopefully we can get core members of the media to hear and understand this message. I have little hope of that, but simply had to say it. Time to find people to share this with.

[@Miata822]

@@TonyFisherPuzzles Core message = There are very, very many variants. Being a variant *Does Not* imply an alteration of the virus' transmissibility, changes in the disease it may cause, or susceptibility to antibodies (from vaccine or prior infection). Think of the exaggerated headlines we have seen about B.1.1.7 and others that are speculative at best. The "UK variant" has not shown enhanced transmissibility or become dominant outside of the UK. Scaring the public and potentially implying that vaccines don't work is counterproductive to public health even if it is a great way to get clicks on a news story.

[@ourworld215]

I watched your Virology Course in 2019. I then found myself glued to our winter 2020 courses. I so appreciate your dedication to teaching in terminology that is accessible to me a 45 year old plumber. While I research for fun all sorts of topics this last year has been less about random thoughts of history and science and far more about the medical situation we have found ourselves all effected some to their very foundations of life. I use your weekly shows and your past courses as reference points when evaluating new information or looking at past findings. This is because I truly believe your work is about the knowledge and not at all about politics and / or money. I've seen you bring up something you were mistaken on and stand firm in the media 'scariant' before details. That's integrity over profits. Thank you

[@Stefan-gh7xr]

Sorry, that was a waste of time. No viruses has ever been isolated or biochemically characterized from its full form.

[@terrydoyle1141]

Thanks, Vincent. You're doing a huge service combating the miasma of confusion and ignorance. More of these smaller spoonfuls of teaching, please.

[@fernie5128]

Vincent! You Rock! Thanks for all you and your talented colleagues do for us! Cheers from Minnesota

[@ashaka-maat3072]

Like other commentators who are not medically trained my first stop moment was what about the virus being isolated from the propagating solution. How does that work?

[@shatteredknight1129]

Thumbs up! This is very helpful. Thank you. I'm not a med student. My field is more mathematics and engineering. But my main study is intelligence, epistemology, logic. The study cells, genetics, viruses, building blocks of biology has been a major past time of mine for the past few years. This channel has been of amazing benefit to me. I honestly, am apprehensive about the word "virus" as terminology. Because of what it implies. Because I could easily consider exosomes to be the same thing. But with no harmful connotation attached to it. The problem I'm having with this channel is not finding any sort of information on the validity of sarscov2. As a strain, and its incubation properties that supposedly make it more dangerous. As far any evidence I've seen. All illnesses in the past year have been no different than any standard flu, corona, rhino, etc. I have seen absolutely zero indication anywhere that proves there is anything new or more dangerous that news is embedding into the population. Thereby, contributing to their fears and susceptibility to illness. And this applies to government officials and WHO as well. As I understand it, over the past decade, WHO has significantly diminished their criteria for declaring a pandemic. Therefore, this supposed 'pandemic threat' would have never been mentioned or heard of, according to WHO's prior criteria. Then there's the testing. As far as I understand it, the primer enzymes used for replication of corona, have no bearing on the strain of corona. So it seems that tests can only determine presence of corona. Not strain. I was a bit disturbed watching TWV last year in the early stages of this upcoming threat because of somebody saying this is the real thing, it's actually happening, etc. What? No information on experimentation to actually determine if it's a real thing by anybody in that podcast. And just randomly saying it's the real thing based on what exactly? I haven't watched every single video on this channel. So maybe there is something I missed. But my question is about evidence of the existence of this sarscov2 strain, and evidence that it's actually in any way more dangerous than common corona viruses. What exactly is the science that this is indeed a real variant of corona. And if it is a variant, what evidence is there regarding the claims about this variant being significant enough to be a strain, and more dangerous. Likewise, how are these tests even determining strain if the basic primer for replication of corona doesn't differ for any variant? Thank you.

[@zuhairyassin505]

what i like about professor vincent is his technical and elegant terminology

[@anne-marie8018]

Thanks, Vincent. That was so clear and presented so calmly and professionally. Just great. Is that TWIV 3 1/2 for this week, haha?

[@livingroomc]

Questions: 1) are there any actual isolates of “the virus”? 2) if not, why? 3) if not, does it matter in terms of developing treatments, vaccines, etc.?

[@himadrinath704]

Thank you Sir..for this great lecture..like you always do. Big fan of your book.

[@silviopina_111]

Bravo Vincent!!! ❤️ I hope you know you are loved and appreciated by many. Keep up the good work and stay safe. BTW, I just read a "fun" novella by Jack London, "The Scarlet Plague" 😱 What a scary, sobering tale. It almost makes one feel better that WE didn't get it so bad. The most sad thing really is not the virus... it's "us"...😭😭😭

[@silviopina_111]

@@wendygerrish4964 It sounds like it was that as well as a combination of various pathologies and general "intense living". I didn't realize how young he was when he died. I found a great Audio-Book version, so it made it all teh more gripping!

[@janpat7373]

Thank you Professor. A gem of a video. Hope the P1 stays in the variant category!

[@medicussapiens]

Excellent and much needed education. Thanks a lot!

[@jamesfoxca]

Thank you for sharing this information. James

[@narancauk]

24:39 ''Media scares you that is how they get your attention'' ----and how they control you.

[@catherinebauroth4828]

Your videos have taught me a lot. Thanks!

[@tjellis1479]

If you say Covid19 three times....yep you tested+

[@rijamor]

From the UK my thanks to Vincent & his colleagues for some very useful and informative sessions. I wish we had someone over here doing the same thing. Perhaps then we wouldn't have the hysteria and chaos induced by our media and government.

[@yorkcyclist]

Agreed, from UK here too, but I will point out that Dr John Campbell's videos are worth watching

[@rijamor]

@@yorkcyclist I have watched his videos and they are generally quite good, but it's all getting a bit weird & cult-like plus the content's a bit repetitive now.

[@rijamor]

@@TonyFisherPuzzles I've watched a variety of subjects from Vincent: mutations, virus evolution, vaccine efficacy, etc. All very informative. Where's the evidence any of these mutations (they're not different strains) are more deadly?

[@Ludwighaffen1]

looking forward to hearing your thoughts on the current variants!

[@TeriAnneAshley]

Dear Professor Racaniello, thank you for investing time in so eloquently educating non-scientist in the language of your expertise. I believe the survival of human kind, perhaps our planet, will pivot on the collective elevation of scientific "literacy." Your ability to translate complex concepts into digestible explanations for the uninitiated is a significant gift to us all. Deep respect and admiration - Teri Ashley

[@cab5917]

Excellent explanation. TY

[@teresahuckabee6879]

Very Informative eased my worry a little bit, thank you.

[@benmcdonnell4167]

Thank you. Wrt what's happening at 5:00 I got lost. Is each one of these genome sequences taken from an isolate from a defferent subject? Or are there different isolates from one subject? Or can many different sequences be taken from one isoate. If it's the latter, how can the same isoate provide different sequences?

[@beckmack1994]

Good point! vincent has to update his textbooks and his 20 year old knowledge

[@jenniferwinsor7740]

Thank you. That was very helpfu.

[@operationacoustic9273]

Hopefully some news outlets can learn something from this video.

[@yengsabio5315]

Indeed! I hate it when I hear words being misused esp. in this case.

[@gaurav7384]

Thank you so much sir for this Wonderful informative session you are the best virology professor in World 👍👍

[@redataha4352]

Great thanks Dr. Vincent Racaniello

[@salvadorhirth1641]

Thank you Dr. Vincent, for taking the time to teach so much in an accessible language.

[@silvanowendel3682]

Thanks for that. Very helpful. How would you define a lineage in this group of terms presented here? Silvano Wendel, from Brazil

[@Longin58]

How do you know that what you are growing on the medium is the virus you are looking for? In the sample from the nose are surely millions of different microorganisms, so how do you know which one causes the symptoms? Don't you need a control sample to make sure that a "healthy" nose doesn't provide the same virus?

[@sithwolf8017]

It's called a healthy negative control culture.

[@hoplite7644]

Thanks Vincent!

[@billannau7668]

You don’t mention purification

[@link1825]

we want vincent to play his guitar in a TWIV sing along!!!

[@RiDankulous]

There were a couple of poems read on air and one or two that I thought were hilarious. Probably wouldn't be hard to sing along with a basic tune.

[@mindbodyspirfit]

Also, Can you talk about the sea slug that ate the algae and got it's DNA and became a photosynthesizing slug....

[@habtamubiazin9869]

This is helpful and interesting. I hope you will have a lecture on genotypes, subtypes, isotypes, clades and biotypes as well.

[@benmarandi3632]

Very valuable video. I wish some people take a time to watch this video. Your method of teaching is unique because you are able to explain a very complicated subject in an easy way to understand. Thank you

[@bushbuddyplatypus]

great but isn't the gaping hole that the variants are derived by highly speculative software processing of material which contains many unknown organisms?

[@deweyturnbow7730]

What is the fluid in the tube?

[@mhlevi]

Very clear...ty

[@thewellnesscodebyalex]

Hello, first time here. Question: Have we isolated Covid-19 using the original koch's postulates or the modified Koch’s postulate?

[@gerontodon]

Well, you can see from the explanation of 'isolation' he gives at the start of the video that it wasn't the former at least.

[@BioLogicalNerd]

How does Koch's postulate connect with viruses Miss compared to say, bacteria or fungi??

[@victorc4518]

Koch's postulates are meant for microorganisms. A virus can't be isolated in that way.

[@michaelmuldoonmikesm08]

where is the cov2 isolate in a court of law ey?

[@trishc9200]

Hi Vincent - another great video thanks. I got a bit confused when you started to talk about clades. What is the difference between a clade and a variant?

[@philliphugh3347]

Thank you Vincent 👍👍

[@AndriNieuwoudt]

fantastic job! I hear you talk about fitness, founder virus. Maybe some clarity?

[@wallaceanature2788]

Thanks for these definitions. I wish the doctor would tell me the name of the serotype I got this time around every time I get diagnosed with dengue. The last time, January 2021, I was diagnosed with dengue for the third time since 2008, not sure if it was false because I then also tested positive for SARS-CoV-2 in an antigen swab test after testing negative in SARS-CoV-2 serology test. I want my virus infection badges of honour to reflect the most accurate description available. Second time I got dengue (2012) the first doctor I went to for a diagnosis (in Indonesia) said it was just a "typical virus" and did not want to bother examining my fever profile or do a serology test. Am wondering how many virus pass through communities like this "undiagnosed" before finally infecting someone who has access to a professional doctor.

[@stephsf9169]

Bravo. Many thanks.

[@jamesmadison4834]

Thank you for the explanation, viruses are so cool!

[@israelramos7441]

Thanks a lot professor!! All your videos make me get used to molecular biology easily!

[@penelopegreenland3537]

Thank YOU!!!!!

[@JuanchoCorreaOrtiz]

So, do viral variants differ in their genotypes from an ancestor on a specific single clade?

[@nplnpl3]

Thank you Vincent for an excellent video explaining strains and isolates! You are provide a great service to the world with your outstanding educational podcasts and videos.

[@Stefan-gh7xr]

Which isolate? Do you know what the word "isolation" actually means according to the dictionary? Look up articles of virologist Stefan Lanka to really understand viruses (spoiler: viruses are not contagious, they are created by our own body in its full form).

[@victorc4518]

@@Stefan-gh7xr Bruh. "viruses are not contageous"? I must have missed that in undergrad virology and epidemiology.

[@Stefan-gh7xr]

@@victorc4518 you read a textbook and you think it is real without questioning if virology adheres to the scientific method

[@victorc4518]

@@Stefan-gh7xr May you clarify how your form of education is correct?

[@Stefan-gh7xr]

@@victorc4518 Do you know what the scientific method is?

[@westfield90]

I wish he had been advising government and media for the past year instead of the sensation seeking incompetent fools we’ve had.

[@tikster67]

@@TonyFisherPuzzles hahahha! This commenter could be commenting from any country. Fyi, its the right wing people who are against the goverment response to this virus

[@ataurrahmanbhuiyan6858]

I love you so much Mr Vincent.

[@stevenbailey5349]

Thank you for explaining. I recently had to try to calm someone down over the new variant news, because he said it was the end of the world. Variant turned scariant by news.

[@1isaacmusic]

Excellent ! Nextstrain is a website I've been showing people for a while now, but methinks it's a bit too technical for the average layperson. Question: Do you think it's possible that SARS-cov2 is related to PRRS virus ?

[@patrickcallahan2210]

Great info! Much appreciated!!! A bit off-topic but I have never heard the word nomenclature pronounced the way you do. Maybe it is just a regional thing but it caught my ear :) Not that I'm an expert in any way.

[@salvadorhirth1641]

Dr. Vincent, can a reverse transcriptase from a retrovirus capture a mRNA from another virus species and assemble then a correspondent DNA sequence that could be integrated into cell DNA if a viral integrase is active in an infected cell?

[@ti_bui9481]

Reverse transcriptase needs a primer specific to the sequence that you want to make into DNA. For a random mRNA, the chances of that primer randomly fitting at the end of the mRNA in order to transcribe it to DNA is minuscule. For a primer with a length of 20 nucleotides for example, the random chance of it base pairing at the end of an mRNA is 1/4^20 which is around 10^-12 or 10^-10%. To put in decimals that would be 0,0000000001%. And I’m being conservative with only 20 nucleotides in a primer.

[@salvadorhirth1641]

@@ti_bui9481 I didn't know that. Thanks.

[@ti_bui9481]

@@salvadorhirth1641 No problem! I'm happy to answer! If you have anymore questions just ask.

[@Sliverth]

Thanks!

[@timmcgrath9708]

I thought virology was a science, not a humanities subject.

[@haldanesghost]

Almost every one of those genomes are nearly unique. I’m sitting in front of the whole database as I write this and can confirm the professor. The idea of a strain is meaningless. The quasispecies is real.

[@jcr723]

when a genome is obtained for an isolate, is the genome take or "measured" multiple times to get statistical dominant genome?

[@ravichandra3210]

No .. any genome was never taken out of any isolate so far. They take whole genomes of everything in the biological sample on the swab. SWAB = human Nasal epithelial cells + human mucosal cells + human white blood cells + few hundred types of Bacterial and fungal cells that naturally grow in nasal cavity + Pollen grains from any flowering plant nearby. NOW ... Mix that with monkey kidney cells or some other animal cells called VERO cells. Then mix them all finely and extract the genetic material of all the cells mentioned above. Add a primer and pray to god it attaches to something n amplifies it. Amen.

[@chrisdodd8979]

The problem, is that when it comes to selling newspapers or advertising space on social media, the correct term and usage doesn't matter one jot. Bending the truth and changing facts are part of the game. Education is one thing, profit is something else.

[@jamesleem.d.7442]

Excellent ! CNN and MSNBC talking heads should be required to study this presentation.

[@anafuentes2496]

Bwahahaha. As Carly Simon and Sweet Baby James would say: "Mock-Ing, Bird, Yeah...Mockingbird now, well everybody have you heard? He's gonna buy me a mockingbird..."

[@carenrickhoff1083]

Thank you for trying to bring clarity to terms that are often interchanged in the press and even in the scientific literature. Really appreciate that. Two questions: (1) re: an isolate, does the definition need to be limited to a species of virus rather an any virus? Otherwise, how would one have an isolate of, say, SARS-CoV-2? Of course, this would require defining a species . . . . (2) re: a clade, it appears from what you said and showed in the diagram that a clade is a virus ancestor and ALL its descendants. Is that correct or did I misunderstand? Again, thank you for your many videos and time dedicated to education!

[@bmansour19]

Where is the follow up to this? Would like more info on whether or not these variants are as scary as portrayed

[@janpek3093]

Ii isolate pure viruses ? If You don't mind Thanks

[@biotecheasy9172]

Can we have a detailed class on how to make a proper clean phylogenetic tree.

[@householdone7559]

Hello Vincent. It would be interesting to hear your thoughts also - in a future video - as well as whether the variants are a cause for concern, whether the attention the virus has received and our reaction to it has been warranted (e.g. mass lockdowns that have gone on for months in places). Or whether you think it has been exaggerated (i.e. the fatality rate has been too low to warrant the reaction) and maybe who do you think should be given a vaccine? (0 - 100? 50-100? 65+ vulnerable people etc)

[@trivalentlogic]

the big question - which is not made clear in this video is. does a variant derive from a physical isolate and compared to another physical variant or does it come from a genom sequence? thank you for the sit down vid.

[@mitre1]

What about the Andromeda Strain?

[@raymondglad5593]

The Truth About Virus Isolation 🤫 Dr. Sam Bailey

[@yengsabio5315]

Thank you, Dr. Vincent! Lots'a love, cheers, & Mabuhay, from tropical Philippines!

[@sukeywatson1281]

Is there a Claude an nature from which the first Wuhan “isolate” or more properly gene sequence arose? That is do the insertions such as the polybasic furin cleavage site demonstrate ancestry or does this point to a lab manufactured pathogen?

[@ernestamoore4385]

You mention that "aminoacid mutation" is wrong. However, a missense mutation is a mistake in the DNA which results in the wrong amino acid being incorporated into a protein because of change, that single DNA sequence change, results in a different amino acid codon which the ribosome recognizes. Changes in amino acid can be very important in the function of a protein.

[@victorc4518]

A missense is a type of mutation. I think what he was trying to say is that you can't have an AA mutation, meaning that adenosine can't be mutated into guanine or some new AA. At least that's what I assume he met.

[@cab5917]

Over time how long did it take to mutate and then to find the 3 distinct different polio strains? And why did the strains 2 and 3 disappear in humans? We’re they weaker than strain 1? What makes a strain more virulent?

[@DaveCompton5150]

Strains 2 & 3 were wiped out by vaccination campaigns. Type 1 survives because it happens to be in Afghanistan and Pakistan where war, politics, and religion have suppressed vaccination. Hopefully this will change and we can nuke this disease.

[@bobn1955]

Nice strat.

[@GloriaInvictis]

So, does that mean that any true new strain has to also be a new serotype? Does that work in reverse - are all new serotypes also new strains? Same for genotype and variants - they seem to be two words that describe the same thing. Did I get it correctly? Edit: in both cases the distinction seems to be only the method through which the new virus was described, not any physical difference in the virus itself.

[@yatrix3057]

Hi Vincent. I really enjoy your videos and podcasts. I have a question for you. Is it possible that you can explain how is the efficiency of a vaccine calculated? There are many videos circulating in Mexico that create a lot of doubt on wether to apply the vaccine or not due to this topic. Please enlighten us and help us change this fear in our people to get the vaccine.

[@bullymaguire632]

You see how many people were infected in the control group and in the vaccine group If the numbers are equal it's 0% effective, if there's more in the vaccine group it has negative efficacy, but if there's more in the control group the vaccine is effective Then you divide the higher number by the lower number and the conclusion will be "the risk is this many times higher in that group compared to the other" and then you just convert Like, if the risk is 10-fold higher in the control group the efficacy is 90%, if it's 20-fold higher it's 95%, 50-fold is 98, 100-fold is 99, you get the picture But if you don't remember these specific relations you just gotta grab the number and divide 100 by it, then you subtract it from 100 Example: The vaccine reduces your risk 10-fold So you divide 100 by 10 That's 10, so you do 100-10 and you get the 90% efficacy from earlier