Dominic writes:

Dear Dr. Racaniello and wonderful colleagues on TWIV,

I’m a hospital internist (hospitalist), and I love your podcast which I discovered back in March when I was truly desperate for some reliable information about COVID-19. Thank you so much for your outstanding work! 

Have been listening to each new release ever since, but unfortunately time often prevents me from listening to the whole episodes.  If you already addressed this question recently, please ignore.

Sampling of most patients suspected of having COVID-19 continues to be primarily through the uncomfortable and (for the collector) somewhat risky nasopharyngeal route for PCR testing.  I think a couple of months ago, you mentioned some early work suggesting that the oropharyngeal approach or even just saliva samples could be just as sensitive and specific.  What do you think of  studies to date to answer this question?  Should we change our practice?  The work I have seen does not include huge patient numbers, but the results seem encouraging.  I have listed two references below, but you are probably aware of additional and perhaps larger studies.

Again, your work is greatly appreciated,

Dominic Jaeger

 McCormick, Clare, et al.  Saliva as an Alternate Specimen Source for Detection of SARS -CoV -2 in Symptomatic 2 Patients Using Cepheid Xpert Xpress SARS -CoV – 2.  J. Clin Microbiol.  May 15, 20202.  

Iwasaki, Sumio, et al.  Comparison of SARS-CoV-2 detection in nasopharyngeal swab and saliva.  J Infect.  2020 Jun 4.

PS 1:  I’m sure you will talk about the recent open letter by Drs. Morawksa and Milton and signed by many more regarding airborne transmission of COVID-19.

PS 2:  I loved Dr. Griffin’s concise, erudite review of evidence-based medicine some weeks ago.  It should be required listening for all medical students and politicians.  Quality medical care has been advanced greatly by rigorous science.  Sadly the federal government’s premature imposition of comprehensive electronic data management systems has set us back years in other ways, such as through interference with the doctor-patient relationship, decreased consideration of differential diagnosis of clinical symptoms and findings, production of a great deal of “garbage” in health records, and physician burnout.  

Diane writes:

Hello- I love your show and listen on my phone in installments while I am out cleaning the barn every day. I have found that listening to science and fact-based discussion can be an effective antidote to my frustration and despair over the state of our country and our deep political divide. I am a retired RN/Public Health Administrator,  mother of a virologist :).

Here’s my question, perhaps for Daniel Griffin –

I have a good friend who is an RN on an OB unit in small rural hospital.  She was recently exposed to SARS CoV-2 at work because a traveling nurse who also works on the unit flew home to Houston to visit her boyfriend. When the traveling nurse returned to work she was asymptomatic but  “voluntarily” tested, went to work and then a day later received her positive test results. So, she spent the day, albeit with a mask on, in close quarters with a a few other nurses/staff, and a handful of  OB patients and newborns.

On top of all this, my RN friend received a phone call from a contact tracer who said that she, my friend, was not required to have a test for COVID before returning to work since she had been wearing a mask on the day she was exposed.

I would love to hear your thoughts on how this could have been handled differently. To me the traveling nurse should have been required to quarantine and test before returning to work, having visited a known hot zone. While I understand that is not easy with limited staff, it seems more prudent than allowing her to potentially infect and sicken patients and co-workers. Also, with testing readily available in our community, shouldn’t contacts of a positive case be required to test? Not testing seems overly reliant on the efficacy of masks. 

Thanks for all you do!


Steamboat Springs, Colorado

Bob writes:


Great show. Not sure of the temperature here in Philadelphia, I don’t have that app on my phone.

Lots of buzz but very little science regarding giving inhaled steroids early in the course of Covid.

Any thoughts?

Thank you,


AMR writes:

Hi Vincent and others,

I am a septuagenarian mouse immunologist who started listening to your podcasts a couple of months ago (you were recommended by my grad student).  I have really enjoyed listening to all parts of your podcasts (including the banter) during my daily 2 mi walk (with my mask on)!  I work at the Univ of MA Medical School (Worcester) where we are now back at work  – we are required to wear masks at all times when we are on campus and now tested every week by nasal swabs!  I feel safer at UMMS than in many of the parks in Worcester where no one other than me is wearing a mask.  Needless to say, COVID-19 is a common topic of our physically-distanced hallway conversations back at work.  So here is the question that came up today – is it possible that older individuals are more sensitive to infection because more of us have had our tonsils removed?  Perhaps tonsils play an important role in COVID-19 immune responses, so one might predict that tonsil removal would correlate with more severe disease. Interested in your thoughts!


Lisa writes:

Dear TWiV team,

Thank you very much for your wonderful podcast.  Without it a lay person like me has almost no chance of finding logical and scientific information about this pandemic.  I especially want to thank Dr. Racaniello for defending the Chinese scientists in the Wuhan virology lab.  You have done more to dispel misinformation than any other person/organization I have seen.  You helped me understand how the novel coronavirus could have risen naturally through no one’s malice.  Various conspiracy theories such as the virus was man-made or had escaped from the lab were widely circulated amongst the Chinese community as well.  When you all were discussing how the virus could have been picked up by someone unknowingly, it made so much sense.  That discussion reminded me, when I was little, I once found a bat by the foot of a tree in the school yard.  I thought I would save it and took it home with me, completely unaware of the potential danger.  I was lucky and no harm came from it but it could very well have been disastrous.  I also was unable to save the bat in the end.

I am Chinese but am not currently living in China. I know I can only speak for myself, for what it is worth, I do not feel any member of the TWiV team has been culturally insensitive in your discussions.  The only people who are “culturally insensitive” are the people in the media perpetuating the falsehood that the pandemic is caused by Chinese people habitually eating bats.  I wasn’t even aware that bats were being eaten until I heard it on US news stations.  Now I often hear stories that Chinese people are being yelled at, physically attacked in the US and in Canada which is a shame.  If only more people will listen to your podcast and realize that this pandemic is the result of us, HUMANs, encroaching on the natural habitats of wild animals.  I believe that continuation of commingling of livestock and intensive animal farming will likely create future outbreaks.  Pandemics happened before, it is happening now and it will happen again in the future if we keep burying our heads in the sand.  I also share the fear that this pandemic is but a trial run for the much bigger disaster that is headed our way as a result of climate change.

Sorry for the long email, what I have to say next is probably not a good idea to be read on the podcast as you might ignite a barrage of attacks.  I felt I needed to send an email into your podcast when I heard you reading a letter from “An Upset Chinese Listener” on TWiV 638.  I was upset by the upset listener’s comments.  I cringe when people describe themselves as Chinese such and such which creates a false impression that they represent all Chinese people.  No one person can represent a group of people and I think it would be so much better if everyone starts his/her letter with the disclaimer “this is my personal opinion only”.  In addition you can never be sure whether the emailer is a real individual or a troll employed by the Chinesegovernment.  I am not sure if you are aware that Chinese government employs an army of internet commentators in an attempt to manipulate public opinion to the benefit of the Chinese Communist Party.  These people have the means and the motivation to attack organizations and/or individuals online that they deem as being critical of the Chinese government.  

Professor Condit also didn’t need to feel bad about his comments.  In truth, the first thing that came across my mind when I heard that an experimental vaccine was given to the Chinese military was that the Chinese government was using the soldiers as guinea pigs.  I do not believe it is due to an unreasonable cultural stereotype.  Many Chinese people will have the same suspicion because we know that the Chinese government does not value individual citizens’ lives.  We were taught since we were little that all citizens should sacrifice themselves for the good of the country and the Party, so if the government was using its citizens to test experimental vaccines, most Chinese people would not think it was wrong to do so (especially in this case where the safety has already been established).  Soldiers that were selected would very likely feel that it was an honor to be able to make such a significant contribution.  However, Chinese people do not want to admit this to western countries because we know that western countries think this is barbaric.  Ironically, many in the US don’t seem to think that differently any more as a number of politicians are telling the public that they should sacrifice their lives for the economy.  I guess all those in power are not very different and only see the people they ruled over as tools.  

I am living in a very culturally diverse area and I come to appreciate the fact that people are more similar than they realize.  Regardless of one’s skin color and ethnic background, people fall into the same pitfalls.  Amongst the Chinese people, there are those who intentionally produce/pedal conspiracy theories for their own purpose, there are those who are racist, there are anti-vaxxers and there are climate change deniers …  You get the idea.  But it is taboo to talk about it.  

I love it when Dr. Racaniello goes on a rant about some injustice he sees.  Free speech is a wonderful thing and most people in the world do not have it.  It is also more fragile than people realize.  It worries me when I see that scientists and intellectuals are being attacked by the current US administration and also by certain people in the extreme left or right.  People often compare Trump to Hitler, but I think that is wrong.  I see a much stronger parallel between him and Mao Ze Dong.  Mao attacked the scientists and intellectuals in the Cultural Revolution, dismantled the entire Chinese education system and turned the masses against higher learning. Being uneducated became one’s ultimate achievement.   Similarly the cancel culture that is developing in the US universities also reminds me of the Red Guards, students who denounced and attacked the school administrators and professors.  I hope my worries are overblown.  However I think in order to protect free speech, scientists cannot stay out of politics.  Quite the opposite, scientists should get more involved and need to speak louder than the voices of ignorance.  I hope you will encourage your students and colleagues to get involved in politics, run for office even.  There is no reason why the US leaders should only be lawyers, businessmen and actors. 

Sorry for the long rambling and I will stop now.  The last thing I wanted to mention was that I never used to go on social media before the pandemic, so I was not exposed to all the insanity that was out there in the world.  But like watching a car crash on the highway, I am unable to look away now and it is causing me tremendous amounts of stress.  Your podcast feels like a life raft in an ocean of crazy.   So thank you all very much!

 A very thankful listener who happens to be Chinese

Stephen writes:

Dear TWiV: 

A long-time grateful listener, once happily retired physician, until recently. (COVID-19 happened)

 I am still feeling disturbed by the recent listener email in TWiV #638 which was inevitable, the long-standing Cancellation Culture nonsense, endemic on social media washed up on the pristine shores of the TWiV intellectual landscape. Thus, truly becoming a pandemic itself. No one has been more culturally sensitive and aware than Vincent, Rich, Alan and the rest of the panelists. Lest we forget, in the early days of the Wuhan outbreak, local public health physicians were silenced and a few jailed for speaking up about the outbreak. Until the problem got so large that the local Wuhan and Beijing governing forces were forced to admit a problem existed and start to take measures to control it. Valuable time and lives were lost during this period. That afterwards the central government became open and more transparent should not erase the facts of this earlier period.

Your comments on the administration of the vaccine to the Chinese military were intellectually proper and morally warranted. Stand proud TWivers, we need you on that wall, we want you on that wall. The only antidote to this nonsense is zero tolerance for bullsh*t.

Vincent, stay grumpy, stay brilliant!



p.s. I will be more culturally tolerant when the Chinese government releases the more than one million Uyghur Muslims and their families being held in re-education (concentration) camps in the western part of the country

Yuanyuan writes:

Dear TWIV organizers:

I was in the middle of TWIV 638, and was furious when I heard one Chinese complaining about your recent comments on the Chinese vaccine and the military story. I just want to email to show my support. That one Chinese person doesn’t represent most other Chinese in the audience, at least not including me. I came to US for PhD about 10 years ago, and am now studying endogenous retrovirus as a postdoc in CU Boulder in a lab descended from the Elde lab. TWIV was recommended by my PI about 2 years ago when I started long commutes from Denver to Boulder, and I have since become a TWIV fan. When I heard that some of you were going to Fort Collins for the ASV meeting, I told my boss that I wanted to go to see you guys just like fans going after pop stars, even if I wasn’t planning to register for the meeting because I didn’t really have a Virology project at that time (of course the meeting was cancelled unfortunately). My school was locked down in mid March, and I have since started listening to TWIV non-stop outside my car, when I was cooking or taking a walk. I want to acknowledge the fact that in the podcast, you constantly defended China for the virus source from a Wuhan lab, or the Chinese Virology scientific community as a whole. Despite not being very active in social media, I shared “TWiV Special: Conversation with a COVID-19 patient, Ian Lipkin” aired on March 28 on my facebook and twitter, because I want more people to hear how Ian interacted with Chinese virologists in the early days of this pandemic. Another story I want to share is what I had done during the lab lockdown. Because of the pandemic and the lab lockdown, I was actually not very motivated to work on my computational project or proposal writing that I had agreed to my boss in the beginning. Because of TWIV, I was following the cutting-edge CoV research, and in the middle of the pandemic, I came up with a computational CoV project that had nothing to do with my previous projects, which I felt more motivated to work on. 

Sorry for this long email without a real question, but I want to show my support as a Chinese researcher living through this pandemic in US now. Keep doing what you have been doing, and hope one day, I’ll be able to meet my stars in person. 



Charles writes:

Language is my weakness.  This is my first limerick.  I hope it brings you a chuckle.  If I broke a limerick rule or two, so be it. 

There Was Once A New Virus Plight,
That Proved Our Politicians Not Bright.
They Listened To Heads Phony,
Not To The Very Wise Tony.
And Now We Are In A Terrible Fight.



Michael writes:

Dear Members of the TWiV team, 

My first official letter to TWiV.  You guys are great and there is not sufficient time to praise each and everyone for the work you do on TWiV!

I am writing to comment and share that I literally did a spit take onto my poor unsuspecting iPad when I heard your discussion on TWiV 637 (letter from Jonathan in Sweden),  that brass instruments should be made of copper as you were discussing the SARS-CoV-2 output potential from the spit valves and horn bell from brass instruments… the spit take occurred where upon I began shouting at the iPad — Brass is copper!  

Brass, is an alloy of copper and zinc, two transition elements, where copper is the bulk element in the alloy, the zinc is added to confer mechanical and strength properties but also enhances its antimicrobial aspects.  The alloying process is effectively creating a new metal, Brass, a substitution alloy,  where the atoms of the two elements may replace each other in the same crystal structure, the consequence, is Yes,  this new metal is a recognized antimicrobial material with an ability to achieve  a public health claim by the US-EPA.    The brass serves to generate free radicals in concert with the moisture and oxygen to create singlet oxygen and other free radicals or as an electron sink.  

The consequence to the unsuspecting SARS-CoV-2 virus entering the labyrinth of the horn’s plumbing,  is  first damage to the envelope and then the destruction of its message as the virus exits the spit valve or horn bell.  

Silver instruments, are not so good unless they are polished..and on the inside this is unlikely so if the instrument is made of silver it will passivate into a form of silver oxide that is NOT antimicrobial.  

The silver products out there that are antimicrobial, accomplish this by complexing the silver ion to EDTA and upon interacting with human sweat the Na or K ions displace the silver ion that then react with the proteins in the outer membrane and inner membrane rendering them inactive and hence death and destruction. 

Keep up the outstanding work, and some day, I hope TWiM can get to episode 1,000… your likely target before the end of the year, at the rate you continue producing this outstanding podcast.    

Michael @TWiMSchmidt
Michael G. Schmidt, Ph.D.
Department of Microbiology and Immunology 
Medical University of South Carolina

Sam writes:

Hi all! 

It is a crisp 16 degrees celsius here in Nashville, TN. 

Thank you so much for your invaluable work. I usually listen to your podcast while I drive, but since I no longer drive around as much, I have been listening in and out of housework (and not necessarily in the order that the episodes are posted). I finally got around to 596 and was very disheartened at the nastiness you guys receive– especially since you are spreading the most valuable information that can be found during this pandemic!

All that aside, I am a graduate student that works in a virus/innate immunology lab and much appreciated the shout out to the innate immune system in Episode 597. Thankfully, with this being my interest, I know what sources to trust with respect to information on this pandemic and how to interpret the majority of scientific-jargon that often comes with it. Unfortunately, the same can not be said of my parents (and a lot of others that I see on social media, for that matter). Claiming that they all look at “the numbers” and “only speak data”, it is still believed that restrictions related to this pandemic are “a gross overreaction”. Since Ohio isn’t the same as New York, they shouldn’t be expected to stay home. They should instead lock up the elderly/immunocompromised populations and be able to go about their lives. I try to explain rationale and even the science behind the infection as much as I can. I even refer them to your podcast and other sources to help point them in the right direction. Nothing seems to get through, however. The most frustrating part is that they are representative of a large portion of our population. 

How do we better reach those that are so misinformed? Unfortunately, they are not quite on board with listening to a 2 hr podcast nor are they willing to truly understand and internalize the science that I am telling them. I would love if maybe after each one of your shows, you could post a “Facts at a Glance” sheet, which summarizes some of the more important things that you’ve learned from your guests. I would gladly and always repost it on social media (with proper credit of course) and disseminate it to those who need such a resource. I know you are busy and hard at work, and that this may not be 100% realistic… but I do feel passionate about the RIGHT people being heard in the midst of a lot of unnecessary and unhelpful noise.

I wish you all the best and look forward to more episodes to come,

Kindest regards,


Tommy writes:

TWIV newb here, I’m an engineer who went no further than HS biology so be gentle.   I was wondering about the balance between T cell defense and antibodies.  Is it possible our use of vaccines left antibodies to do all the work and somehow our T cell defense mechanisms have atrophied?   If SarsCov2 has some antibody defeating mechanisms built in would that make it more virulent because our T cells just “aren’t what they used to be”?   I’m sure T cells aren’t like muscles and hope you can add some color to how these things work.   Did I understand correctly that sometimes they add things to viruses to bolster T cell responses?

I think the idea was loosely inspired by something I picked up from the book 1491 which said native american populations’ immune systems were good at defending parasites but bad at viruses because of what they were exposed to and that was partially why they were so decimated by smallpox.  I guess if any of this were true native and 3rd world populations would fare better against COVID and I’m not sure there’s any evidence of that so this is all probably poopycock.   Thanks!


P.S. You guys should “Countering the miasma of anti-think” on a TWIV t-shirt.  I’d buy it.

Sonrisa writes:

Hello to all the TWIV crew wide and far.

I just finished a morning walk here in Vermont.  It is very muggy 77F/ 25C/ 298K/ 537R  (Rankine, who uses this scale????)

I wanted to say thanks for Vincent’s recent rants/ guilt-trips about those of us not listening to the non-Sars-CoV-2 TWIV episodes. Feeling the heat of guilt in the back of my mind this morning I settled into episode 633:Singapore Viral while making breakfast. Thanks for the conversation with Ashley St. John about her research on Dengue that connects Mast Cell Activation to tryptase release that induces breakdown of endothelial cell tight junctions.  Sparks went flying in my head as I listened.  I suffer from Mast Cell Activation Syndrome (MCAS), so I have been spending a good amount of time learning about it since my diagnosis.  And almost everything I have come across so far in relation to MCAS is about the Histamine release and treatments related to controlling histamine.  But learning about this effect of Tryptase on tight junctions has a lot of puzzle pieces starting to fall into place in terms of migraines, digestive upset, severe blood pressure drops etc. and it is opening up new questions to consider as I learn more about my condition and ways to help moderate the effects.  I will be sending Ashley’s paper to my specialist.  And after writing this email I will probably be going down a research rabbit hole trying to read more about tryptase. Always sometime fun to learn somewhere.  Thank you and the whole team for all you do and share, it is about so much more than just viruses! 

Also, I wanted to say that I have skipped episodes, including ones about Sars-CoV-2, but it is not from a lack of love for all things viral or the chatty banter, both of which I enjoy immensely.  It is more just that there are a million things I want to learn about and some days I am focused on other things.  Like learning more about Mast Cell Activation Syndrome and Lyme Disease, rehabilitating our rescue dog thinking of new ways to assess my students for this coming year of remote/not-remote learning however it may end up. I teach highschool maths and physics.  

Viruses have always held a special fascination for me, even as a kid.  I must go back in your archives to look, but I assume you have some discussions somewhere in there about whether viruses are living or non-living things. That was always a question I was repeatedly thinking about.  I grew up in the high desert west, summer was always wildfire season.  My brain would always try to connect the ideas of how viruses replicate and have methods to propagate themselves from host to host and how big fires build their own thunderheads that travel off and strike lightning somewhere further along, starting a new wildfire…. replicating with the help of a host, in a way like a virus. After completing my undergraduate in Physics I did actually look at Virology PhD programmes.  Although I did not choose that path, the curiosity is still in me.  And I would say thanks to Sars-CoV-2 I stumbled on your podcast and have been thoroughly enjoying every bit of it and it’s been rekindling my fascination with viruses. 

 Also a question for you. I teach math at a ski academy. All my students are dedicated athletes with dreams and goals to reach the most elite level of their sport.  In one of Daniel and Chuck’s recent updates they mentioned about the long term impact on lung function in the context of athletes that might never be able to reach or return to their full potential.  I am curious if you guys can discuss this a little more or point me in the right direction for other resources about how to potentially view the impacts of long term complications from COVID-19. And importantly, how that view changes in terms of risk when you are considering normal people versus athletes operating at the limits of their physical potential.  Just thinking of all my students.  

Thanks again! And stay chatty and grumpy and funny.


Marissa writes:

Dear Dr. Racaniello and TWiV-ers, 

I’ve been listening to TWIV for the past few months and get all my COVID news from you. I especially enjoyed TWiV 609 with Susan Weiss and, as I am an ecologist, your episodes with Peter Daszak. I’ve also started listening to TWiP and the non-COVID-19 related episodes. 

I’m writing to you because I am trying to have a COVID-conscious wedding. I have decided on a venue that is all outdoors, way up in the Sierra Nevada mountains. The venue is isolated, and there is no chance for strangers to happen upon it. Everyone on site will be people my fiance and I will have invited or hired. I’d like your opinion on if this is a dumb idea or if you have any suggestions to make it safer. Here are the precautions we have in place: 

– venue has space for 200, but we’re capping the invite list to 30 people
– a majority of those attending will be camping 
– masks will be worn at all times unless eating or drinking (we will be providing masks)
– no buffet
– no serving staff
– no dancing 
– individual’s bathroom use is restricted to an assigned bathroom 
– tables in reception area restricted to one family group per table and 12 feet apart to allow for no masks while eating
– handwashing stations positioned throughout venue
– sanitizing stations also throughout venue
– people spaced 6ft apart in ceremony area with mandatory masks
– recommended COVID test within 72 hours of arrival
– stay home if you feel sick
– stay home if you have EVER tested positive
– stay home if you have ever come in contact with someone who has tested positive
– stay home if you aren’t willing to adhere to our rules

Do you think these are sufficient? Are there any other rules you recommend or do you think we should scrap the whole idea?

I’ve put together a video talking about the precautions we’re going to enact. We’re using this to pitch the idea to our guests. 

The video is here if you have 10 minutes to take a look: 

Thank you for all your hard work. I recommend TWiV to everyone. I am a biological consultant in California, and listening to you makes me feel like I’m chatting with my colleagues. I appreciate your respect for one another and your dedication to high quality science. 

Stay safe, 

(& Dacklin)

Hilary writes:

Listener since March – like a whole lot of your non-scientist audience – with a lot to enjoy and not much to contribute till it this hit me:

Your 4-year-old listener has nothing to worry about the transmission of coronavirus via the human fart – after all, not even the most freedom-loving politician opposes the idea of masking that orifice….

Hilary – Oakland CA  

Stephen writes:

Dear TWiV team,

Alan (and possibly other hosts) have on a few occasions blamed CDC for being the only one initially to develop a test. While I won’t say that CDC hasn’t had problems (there were definitely issues with their initial assays), there are two problems with this.

First, this was not CDC’s decision–it was FDA’s. And it was made on seemingly reasonable (before the pandemic) grounds that in the case of an emergency, Laboratory Developed Tests (LDTs) from high complexity CLIA labs would require an Emergency Use Authorization (EUA) like all other diagnostic tests. Normally LDTs, which are only used in house and not distributed to other labs, do not require FDA authorization, but because of concerns over their accuracy, and the importance they have in an emergency, they do need an EUA in an emergency situation. I’m told that FDA tried to impose restrictions on LDTs in all situations in the Obama administration and you can see some of their concerns here:

The FDA basically got around this by issuing an EUA for all LDTs from a high complexity CLIA lab at the end of March. 

The second issue is that CDC was not the only diagnostic test developer that could get an EUA, they were far and away the first who could get approval, possibly because they have a leg up since they’re a sister organization to FDA, and since commercially developed tests needed to wait until it became clear that there would be a market.

Alex writes:

Hello TWiV,

I’m an entomologist working as an Agricultural Biologist/Weights & Measures Inspector. 

To be PEDANTIC, on TWiV 637 (and others) while answering email, you all had suggested that the United States should adopt the metric system because of its various inherent qualities. I wanted to chime in and mention that the US is, in fact, a metric SI unit adopting country. 

The Measurement standards, for ALL measurements made in the US, are housed at the National Institute of Standards and Technology (NIST) and are all based on metric measurements that are traced to an international standard. All measurements can be traced back to the national standards.

The United States simply adopts imperial units locally for each State. Through this adoption process, measurement values undergo an additional conversion to imperial units for day-to-day use but are still based on the metric national standards at NIST.

I love listening to TWiV but love TWiP even more! Keep up the great work! 



Alex Nguyen Photography | Insect Macro Photography

Corey writes:

Hello TWiV folks,

  It’s warm, dry and windy 29C here in Champaign, Illinois, home of the University of Illinois at Urbana-Champaign (UIUC). I’m just a computer support person that has been married to a Nursing educator for a long time, so much of the science goes over my head, but I recognize many of the terms. I’ve been listening to TWiV since March and am glad to have some science based common sense and reasoning on the pandemic and other things viral. I particularly have enjoyed the episodes recorded back in 2019 in Singapore and Georgia that seem to each presage the pandemic in their own way.

Our campus of 50,000+ students is currently planning on reopening on schedule in August and as part of that process we will be mass testing faculty, staff and students using a saliva based test. The public details of the plan are in the Health and Safety section of the FAQ at

I believe the details of the saliva based test are in the following paper:

– What are your thoughts on this test? 

– The sensitivity/specificity were calculated with a small number of samples (100, only 9 of which were positive with a gold standard test) AND the samples were handled in weird ways (freezing for a while, changing how they were processed).  So do we actually even know anything real about the +/- ?

– They said “using duplicate testing of samples, false results decreased to 0%”.  Duplicate = what, two test runs? More? Do they intend to perform repeated testing of samples as part of the process, or just for this research? First run has a 11% false negative, so based on prevalence they’d have to “duplicate test” almost all samples to get the benefit of increased accuracy, right?

Thank you for all you do.


(p.s. These questions were pooled via slack from a group of TWiV listeners who were all residents of the same dorm at UIUC many years ago.)

Dave writes:

Hi guys,

My name is Dave Beddow and I am a physician assistant (PA) student out at a program in rural Tennessee. The current pandemic has turned me into a listener (silver lining, right?) because I wanted to know about this particular virus (and viruses in general as a consequence of listening). 

With the talk of a possible mRNA-based vaccine in the works, it had me wondering. Does this type of vaccine require refrigeration to remain stable and biologically useful? I am curious if it doesn’t require refrigeration, how, given that mRNA is relatively quick to degrade? Through additives alone… or could this be accomplished by other means?

Just curious from a global health perspective as I am thinking – if it DOES require refrigeration – this would present logistical challenges getting the vaccine to remote areas or less industrialized nations.

All the best,