Amara writes:

Dear Dr. Racaniello and team,

I’ve been listening to TWiV for several months now and greatly appreciate your work. I have a “which shot?” dilemma (a very privileged problem to have, I know) and would be grateful for any thoughts you might be able to share by Friday 4/9, if at all possible. 

I am in the Phase 2 trial of Sanofi’s investigational adjuvanted recombinant protein COVID vaccine, and received my second dose three weeks ago (3/17). I became eligible for an EUA vaccine in my area the day after the study began, but agreed to wait 6 weeks from the first dose so that the study team could still use my data, getting an approved vaccine no earlier than 4/7. Two days ago, I made an appointment to receive dose #1 of Moderna this Saturday 4/10, but today received the opportunity to make an appointment for J&J, hence the urgency. I know the best shot is whichever one someone can get first and would have been happy to get any of three EUA vaccines, but since I unexpectedly have this choice, I’m not sure what is best to do in conjunction with the experimental vaccine. 

If I had not already received two doses of the Sanofi vaccine, I would choose Moderna because of the higher efficacy rate. However, I have had two doses of *a* COVID vaccine (th

e Sanofi study does not have a placebo, but I don’t know which dose level I received) and it’s likely I have produced antibodies because I did have side effects from the second dose. As such, would it be more advisable for me to go with the single-shot J&J vaccine rather than getting four doses of a COVID vaccine within the span of less than three months? Or should I stick with Moderna, even though that might mean severe side effects with both doses? Is there any reason to think one formulation over the other (Moderna’s mRNA versus J&J’s adenovirus) would be “better” following the recombinant protein?

I spoke with one of the Sanofi study doctors and he shared his personal opinion, but cautioned that he can’t truly advise me since we just don’t have any data on someone receiving two doses of the Phase 2 Sanofi vaccine followed by an approved vaccine because it’s never happened before. I recognize you can’t know for sure, either, but as I weigh my choice I’m curious if your team of experts has any thoughts or strong opinions. And I completely understand if you’re not able to get back to me, but thought I would give it a shot, pun intended!

Thanks very much,


Eli writes:

Dear TWIV!

I’m a long term TWIV listener. For a change I have something I wish to share. 

Since march 2020 a group of scientists and citizen scientist (Eterna) have worked on finding ways for better stabilizing mRNA against degradation. I’m one of the citizen scientists. 

With less degradation, cost of cooling could be cut and the vaccine would be easier to handle everywhere in the world. Potential lower doses could be used – because the RNA isn’t degrading as fast. 

Our aim the whole time has been to get our work used for the second generation of the mRNA vaccines. Plus it will have relevancy to all RNA therapeutics. I am hoping you would take a look at our new preprint.

Combinatorial optimization of mRNA structure, stability, and translation for RNA-based therapeutics

Best wishes,


Mike writes:

Hello twiv hosts.

Relatively new watcher of your show.  A friend and a co-worker turned me onto your show early into the pandemic and have been watching ever since.  Thanks for all the great information.

I am a computer programmer and have no experience in medicine or virology so have really enjoyed the info.

I have a question in regard to hydroxychloroquine and how quickly this drug seemed to be determined to be ineffective fighting sars-cov2.

Is there a chance that this drug with some of the cocktail combinations being tried could have stopped both pathways for the virus.

Was it ever tried in combination with camostat mesylate.  It seems like a logical step to me after watching your podcast.

As someone with a statistical background but no virology or medical training;  I look at some of the hospital and world death statistics about HQL usage and do not see anyone really analyzing this data to the extent it should.  I do understand that there are many factors that could affect the post death analysis data that is being presented, i.e., age of population in developing countries using HQL.  A few cross immunity possibilities for other vaccines, just to get started.  The US hospital system data is of course flawed in its own ways too.  No real form of control groups in  both the Henry Ford and Hackensack Meridian data.

In my untrained observation it seems possible that a combination drug therapy might be working yet not exactly understood.

Is this a case of being fooled by randomness?  Or is this a real possibility.

I enjoy watching and thanks again


Simon writes:


I started listening to TWIV in the summer. I have no idea how I found you but i did. Before the summer I’d been looking around for resources to better understand the pandemic and how I should be acting. Since finding TWIV and the rest of I have been inspired to learn.

I religiously listen to TWIV and listen to some of the other podcasts as well especially this week in evolution. More than that I’ve been listening to Vincent’s lecture serious and trying to listen to Briannes as well. So much enjoying that I purchased a second hand copy of Kirby’s immunology and a brand new copy of principles of virology – the latter is by the way beautifully written and illustrated.

I’m just a Silicon Valley product manager in enterprise technology. Many years ago I was privileged to visit welcome trust Sanger institute, one of my customers, and learned about what they were doing. That was 20 years ago so I can see just how far we’ve come in only 20 years.

Moreover my son is 11 in 6th grade and in biology learning about the human organ systems so I’ve also got to work with him as he learned using Miller and Levine’s Biology.

Keep doing what you are doing.

Bruce writes:

My 6 year old grandson caught covid from his grade one teacher. The school sent a letter to his parents to get him  tested  eight days after he was exposed. He was positive but had no symptoms. Then his family were all  tested  and were all positive.  His four year old brother had no symptoms. His parents  did get sick but thankfully with mild symptoms. So my question, my wife and I have had one shot of Pfizer but the next shot is not until August (Canada). We want to get back to normal, can we get together before August and maybe have a sleepover with the grandkids,  I’m thinking the kids have already had it so it should be safe?

PS I like your videos, lots of good info.

Michael writes:

Greetings Team TWiV.

I have been listening to TWiV since last fall when I first heard about this great podcast from Daniel. I am the Chief Medical Officer for the Care Innovation Lab at United Health Group. I support the team of nurses that manages the enrollment and follow-up of the patients who participated in the Clinical Trial on Bamlanivimab for which Daniel is the Principal Investigator (PI). My team now helps patients arrange to get the Bamlanivimab – Etesevimab Cocktail at home or at outpatient infusion centers. 

I currently live in Atlanta, GA. It is bright and sunny today with temperature 82 F (27.8 C).  By background, I am a Cardiothoracic Surgeon.

You have a terrific podcast series. The best!  I have listened to every episode for the past 6 months. And in every one, there is a geographic reference which makes me think … “Been there … I know that place”. 

Last week, in Episode 740 @ 1:31:03 you mentioned Jersey City … my hometown.  Yes, so it really seems to be “This Week in Geography” (TWiG). And, curiously, there is some geographic link to every one of the hosts. Let me explain.

Vincent:  A while ago, you spoke about transferring specimens at the Service Plaza on the Turnpike (the Vince Lombardi Plaza if I recall) many years ago.  Having been at these service plazas many, many times, I can just see it: “Under a dim street light with Burger King in the background, a vial of polio virus changes hands. A car speeds off into the night, bound for an experiment in a lab across the GWB”. 

As an aside, I am listening to all of the online lectures from your Columbia course. These are really terrific. This is the virology course I never had. Thank you for your energetic leadership and your many contributions.

Brianne: I started college right across the street from Drew University … Fairleigh Dickinson. I know the Madison-Morristown area very well. I hope that Friendly’s has survived and is still there for all the college students (and faculty). 

Rich: I changed colleges to … Florida.  Well not exactly, I went past Gainesville and wound up in Miami. Sorry. I wound up spending many years in Miami where I completed college, medical school and residency in General Surgery. After a 2-year fellowship in Cardiothoracic Surgery (New Orleans), I joined the faculty at the University of Miami where I stayed for almost 5 more years. Go Canes … Go Gators, too.

Dickson: My parents moved to Fort Lee in the late 1980s. Based on your description of the view from your apartment, there is a good chance that you are in the same building (or one very close). My parents lived in The Pembroke at 2077 Center Avenue. Their apartment faced the river … the exact same view I hear you describe on TWiV.  My mother was a ‘regular’ at the Plaza Diner. I used to take her to the Assembly Steak House in Englewood Cliffs for special occasions. I understand that both have closed. (I haven’t been back to Bergen County much since my mother died a few years ago.) 

Alan: You can’t make this stuff up …I travel to Towson about every 3-4 weeks to spend time with my partner. She moved there for work in March 2020. I have been to Towson 15 times since then. I will be driving there later this week. We have been walking on the Towson State campus, which is about 1/2 mile away. Indeed, the photo attached to this e-mail was actually taken in Towson last month. (The objects between the coffee mugs are not really donuts … they are actually ginormous plasmids).  Also,  there is another geographic location to mention … Western Massachusetts.  As a kid, I went to summer camp in Pittsfield, right on Lake Onota.  

Kathy: This is a little more tenuous at the moment … apologies.  I was supposed to go to Grosse Point, MI in November to spend Thanksgiving with my partner’s family (Her name is also Kathy.)  The trip to Michigan never happened as SARS-CoV-2 got in the way. Tentatively, Thanksgiving in Michigan is rescheduled for 2021. Everyone will be fully vaccinated, so maybe it will happen. 

My Pick:    Working on The Precipice – This is a terrific 2-part series from JAMA. This is extremely well done.

Working on the Precipice: On the Frontlines of the AIDS Epidemic at the CDC Part I

Working on the Precipice: On the Frontlines of the AIDS Epidemic at the CDC Part II

This story is particularly compelling for me. I was a resident at the time that AIDS first appeared … but it did not have a name. In January 1982, I did a lymph node biopsy on a young man who was very ill with an unexplained illness. The biopsy showed Kaposi’s sarcoma. This was the first known case of AIDS in Dade County, Florida. I have subsequently taken care of many patients with AIDS-related complications requiring surgical care.

Thank you very much for the great podcast. TWiV (aka; TWiG) is the epitome of contagious enjoyable education.


Michael D. Horowitz, MD, FACS, MBA

Danielle writes:

Hello Twiv Team!

LOVE LOVE LOVE your podcast. 

My career prior to graduate school was in clinical research. After undergrad I worked as a study site coordinator on a multi-center surgical trial. Then I worked for a CRO (Contract Research Organization – the contractors who do the research for drug companies) managing data for Phase 1-2 studies. Finally, I worked on the sponsor side with a small biotech company trying to bring a drug to market that ended up not succeeding in Phase 3. In grad school I studied bio-psychology but left the PhD program to home school my children and have been an unpaid educator for well over a decade. It is only because of’s podcasts (virology and immunology) and Dr B’s JAMA Network podcast that I have been able to follow the pandemic without bias and misinformation. The world would be in real trouble if we had to rely exclusively on the media for facts. Thank you!!!!!!

When I look at threads from news sites covering CoV-2 I find a widespread misconception that more people die from influenza than COVID-19. Now that the provisional numbers for the 2020 leading causes of death in the US have been published, I created a weekly graph of COVID-19 vs Flu deaths. I included the leading cause of death, heart disease, for perspective. 

Last fall I wrote an essay about why people were being misled into thinking few people were dying (see attachment) but no one was interested. At 1 1/2 pages it was too long and contained facts which people were not receptive to reading. It is my hope this graph is easier to understand so please share with anyone who might find it informative. 

Keep doing what you do. It is a great service for those struggling for accurate information, a rare commodity these days.


from the Austin area (Cedar Park) 
where the temperature is 71℉ and humidity is 74%.

Mark writes:

Dear TWIV team,

I wanted to let you know that I was finally able to buy Fever and West Nile Story on Kindle. I think your listeners will be interested as only used hardback and paperback copies were previously available. I started reading them and they are fantastic books. 

FYI  and thanks for the recent episodes. 



Here are links:
West Nile Story