Chaim writes:


In addition to the TWiV and TWiEvo podcasts, I listen to Nature News, Signal, You Are Not So Smart, Futility Closet, This American Life, The West Wing Weekly, EscapePod, and Relic Radio Science Fiction, in addition to a couple of Jewish religious educational podcasts.

I use Patreon to support TWiX, YANSS, and Futility Closet, as well as some non-podcast projects. I would love if more content creators used this platform, as I am happy to pay for the value I receive.

Thanks as always for a great podcast!

Jeffrey writes:

Dear TWiVsters,

So long as the discussion has fallen onto second-person pronouns and grammar podcasts, I’d like to enter a quick plug for Slate’s Lexicon Valley. A recent episode from November 1 has a discussion on how the rich ecology of “thine”’s and “thou”s was pared down to “you”. Incidentally, I don’t know how much cross-talk there might be between departments, but the podcast is being hosted right now by John McWhorter, who teaches linguistics at Columbia.

Much appreciation for the great TWiV discussions from a biochemistry lecture in dreary -1C Montreal,


Jory writes:

Hello Tweople,

I hope being called a person isn’t offensive. My question is simple, and relates to the multi-component virus paper. Why, in this case, does multi-hit kinetics necessarily imply that the viral genome segments are packaged in distinct particles? Couldn’t multi-hit kinetics result from a requirement for higher gene dosage? What if each particle contained all segments but many particles were required for infection? If I had to put some money on it, I’d still bet on the conclusion from the paper being true given all of their evidence. However, I also think there may be an issue in claiming that distinct packaging follows deductively from multi-hit kinetics. It would be an honour to have you correct me on this… am I missing something?

Please keep up the good and important work. Combatting my boredom while pipetting is truly a noble cause.


Biology Undergrad
Concordia University, Montreal

Anthony writes:

Senator Menendez YouTube on Zika

Have you considered writing Senator Menendez to express support?  A few words from an independent expert can only help.

In the 14 hours or so that the video’s been up, it’s only gotten 72 views.  

There was the three monkeys — and I don’t mean NHPs in a lab — response to AIDs.  One would hope that government and public would want to make certain that there’d be no next time.  It’s sad — if not a tragedy — that that’s not so.

Thank you.


Basel writes:

Hi Dr. Racaniello,

I don’t know if this message will make the cut for today’s recording of TWiV, but I thought of sharing this news story:

Kind regards.

Josh writes:

Listening to the podcast and I wanted to let you know that there are some of us out there who fell in love the microbial world in college but did not end up in the lab. I’m a physician and my college friend, both of us Molecular and Cellular Biology majors, is a dentist – and this stuff still fascinates us. So much science has happened in the years since graduation and your podcast is an outlet for that part of me to think and explore. I still think about how DNA came about from RNA. Is there any evidence for an evolutionary process? It seems too big of a jump. It’s hard to think of a unicellular organism having the kind of perspective to orchestrate that. Maybe a virus was involved? Any idea? Anyway, keep up the good work. Doctors are busy, but you might want to try to get in with the Infectious Diseases Society of America to target some of the more likely physicians to subscribe.

Finny writes:

Dear Prof. Racaniello,

I have been a big fan of the ‘Wall of Polio’ and your weekly podcast about virology. Often research in Europe barely makes news on the other side of the Atlantic. I thought I’d share a bit about my own work by paying tribute to the original wall by building my own mini ‘Wall of Semliki and Chikungunya’. An MSc Virology student from India, I joined the group of Dr. Tero Ahola at the University of Helsinki, Finland as a PhD student 5 years ago to work on antivirals against CHIKV. Over the course of my research, I had to perform hundreds of plaque assay titrations. As I was about to leave the lab this fall, I decided to keep some of the last plates to build up this wall. These are only plates since last December. Thought you might find it interesting. I attach my CV as well.

Finally, I’d like to thank you for the amazing work you do and your tremendous enthusiasm and passion in teaching people about the viral world.



Gavin writes:

Dear TWIV team,

      As a patron of the show, I have no problem with advertising or how it is currently being delivered. In my opinion, complaints about advertising are more of a distraction than the ads themselves. My own motivation for becoming a patron is a sense of gratitude. I am a second year master’s student in a virology lab, but my institution has not offered a virology course in several years. Dr. Racaniello’s online lectures were instrumental in helping me transition from my chemistry undergrad to a virology master’s program. In addition, TWiV and TWiP keep me engaged during my daily commute. I owe you much more than what I can contribute on a monthly basis, and I am glad that your sponsors are able to make up the difference.

         Below I have included my mini-essay for the book contest. My significant other is a graphic designer, and we share an appreciation for the beauty of the natural world. When we first started dating I gave her my copy of “The Architecture of Molecules” by Linus Pauling and Roger Hayward. It contains pastel drawings from Hayward with a brief description for a lay audience by Pauling (you can find excerpts here In return, she made me a calendar with illustrations of viruses as she saw them (I have attached a pdf copy). Thanks again for all that you do, and keep up the fantastic work. I am patiently awaiting the release of the 6th edition of “Parasitic Diseases”.


Gavin Sowa

Southern Illinois University School of Medicine

P.S. I am fortunate enough to be interviewing at Columbia University College of Physicians and Surgeons on October 24th. I know this is a long shot, but I would be the envy of my peers if I could get my picture taken in front of the Wall of Polio.

                                                   Herpesviruses are like Donald Trump… They’re very successful and you just can’t seem to get rid of them.

   I may be a bit biased by working in a lab that deals primarily with HSV, but I’d like to be a herpesvirus (specifically HSV-2). These large DNA viruses always seem to have the answers to life’s problems. For every weapon in our immunological arsenal, HSV-2 encodes a countermeasure or carries out a preemptive strike. With regard to their preparedness, they are the boy scouts of the virus world.

   In addition, herpesviruses have the confidence to be true to themselves and are only interested in long term relationships. HSV-2 doesn’t rely on a high mutation rate for success. It has taken roughly 1.6 million years to get to know you, and it is perfectly comfortable being itself when you’re together (theory of genetic budget). “Not as clumsy as an RNA virus. Herpesviruses are elegant viruses, for a more civilized age” (Kenobi et al.).

   All joking aside, Herpes Simplex Viruses are capable of causing serious morbidity and mortality as well as significant changes in quality of life. Unraveling their many mysteries may hold the key to the development of novel therapies as well as a greater understanding of our own biological processes.  

He sent:

Anthony writes:

Twinkle twinkle little bat.

I’m glad that you found my letter from the hospital amusing.

That I was allergic to the duck egg embryo Rabies vaccine was a curious feature of the incident.  The doctors told my parents that I was expected to die.  Nobody told me anything and I certainly did not present any dramatic rendition of heroism.  I used the bouts of allergic shock as opportunities for naps.  I spent most of the rest of the time that I was kept in isolation watching TV and drinking malteds.

Thank you.

Bill Spindler writes:

A comment on what you mentioned on TWIV a bit ago. These 2 press releases just came out about a new collaboration between NASA and NSF to study the effects of isolation in Antarctica. It will also rotate some of the NASA flight surgeons through the Antarctic medical clinics.

There is nothing in the 2016-17 USAP research planning summary about this (yet)–I looked again. That summary was published before this announcement was made.

There really haven’t been any of these isolation monitoring studies in awhile, and I’m a bit surprised that this collaboration hasn’t happened earlier…or perhaps it has just taken awhile.

When I saw the NASA press release, I instantly recognized the photo of the frosty eyes at the top of the page…they belong to then-Christina Hammock with whom I wintered at the South Pole in 2005–an extremely impressive and awesome person. I wrote her about it and her reply included the term “selfie” although that term hadn’t really been invented then! (She’s now Christina Hammock-Koch and a NASA astronaut).

I expect to hear more about this NASA-NSF joint program at some point.  UTMB is currently the medical subcontractor for the NSF US Antarctic Program.  I’m wondering if the NASA involvement will supplant some of the functions of UTMB (hiring of staff, managing the PQ (physical qualification) process, and providing telemedicine services).

Christian Otto, the Canadian physician I wintered with in 2005 (he also wintered at McMurdo earlier, and he also summited Everest as part of a medical team) is currently part of the medical research group at Johnson Space Center, as the PI on a project studying “visual impairment intracranial pressure risk” in astronauts.


Bill Spindler’s Antarctica


Paul writes:

To the Twivome:

28C, 62% humidity…the barometric pressure is falling as a small rain system makes its way across southeastern Pennsylvania.

The end of September brings us Flu Vaccine Season!!! And a time to return to the questions around antigenic drift and the need for annual vaccination.

Based on this information from W.H.O. and this handy Wikipedia chart of northern hemisphere recommended strains, I put together the following chart of 19 years of vaccine recommendations for the norther hemisphere and discussion points in the hope that a little discussion will inspire everyone to GET VACCINATED this, and every October.

I am neither a doctor nor a scientist but the chart seems to suggest that:

  •         Strains persist far more than the popular press and casual explanations for the need for annual vaccination suggest. 63% of 59 strain recommendations after 1998 are repeats. 24% of 17 possible formulation repeats were entirely identical to prior year.
  •         Multi-year strain persistence implies that both vaccination and natural infection do not provide multi-year protection against even the particular strain of infection or vaccination.
  •         A universal flu vaccine would avoid the strain prediction problem but there is no reason to think that it would allow us to avoid annual vaccination.
  •         Hypothetically, the inability of immune memory to stave off flu relates to the role of the inflammatory response component of the pathophysiology.
  •         This makes me ask whether passive immunization might be just as effective as vaccination? If so, might it not be easier to manufacture universal flu antibodies than to reliably cause the body to produce them by vaccination?

Chart and legend follow…Do not try to read on air!!!


p.s. Thanks for the great show

He sent:

Anthony writes:

A neighbor recently returned from a trip home to Ahmedabad, Gujarat, India.  He related that the visit was not good because he, his wife, their one-year old daughter and his father all fell ill.  I asked if it was the flu and I was told “No, it was viral.” Reading this:

it appears that this is flu season for western India.  I’m assuming that Influenza was what made them sick.

The CDC does advise travelers to India to have received an Influenza vaccination.

What I’m wondering is if the strains circulating in the US — and consequently the vaccine — are the same for India?  If not, should people going there — and to other locales with Influenza viruses that differ from the United States — get the destination country flu shot?  If this is done, what effect will it have — if any — on subsequently getting the domestic vaccination?

Thank you.

Adam writes:

Dear TWiVsters,

Greetings from hot/humid/cold/windy/rainy/foggy central Illinois.  It’s currently 29 degrees Celsius and sunny, but if this is a normal fall we’ll cycle through those other stages by the end of the week.

With all the Zika coverage in the news and on TWiV, I’ve been paying closer attention to the local mosquito species this year.  We’ve had our usual swarm of Culex pipiens mosquitoes, and I occasionally see a stray mosquito with striped legs, which I’m guessing is Aedes albopictus.  A few weeks ago I was surprised to see a mosquito more than twice the size of a typical Culex/Aedes land on my arm and chomp down for a blood meal.  I’ve seen probably half a dozen since then.  Some googling reveals the most likely culprit is Psorophora ciliata, aka the “American Gallinipper”.  Has this species ever been discussed on the show before?  Is there any evidence that it carries human diseases?  We’ve had some late season rains that likely allowed this species to flourish, but I’m curious why I’ve never seen them in the spring before.  I know what I really need is a “This Week in Entomology” podcast to bug about this, but you folks are my best source for mosquito insight!

Love the show.


(Feel free to cover this on TWiP instead of TWiV if you feel that’s a more appropriate venue)

Anthony writes:

“Mendel, an avid weather lover, later became a weather watcher and record keeper.”

Benedict XVI

Maybe I was the only one that didn’t know about Mendel’s meteorological data collection, but I just learned of it yesterday.

TWiV shares a thread in the fabric of a great tradition!

Hannah writes:

Greetings Twiv team!

I was reading about the National Collection of Type Cultures for work and came across this website, which I’d like to offer as a listener pick.

It’s the site of a British artist who makes art out of microbes: her most recent project, “Microbe mouth”, is probably the best I think: she’s marking art out of “teeth” produced by hydroxapatite-producing bacteria. Some of her older projects are quite interesting as well, from sculpting the concept of a fecal transplant to making dresses that illustrate bacterial communication.

I realize it is not strictly virus-related, but it’s worth poking through anyway!

Love the show!

Hannah from Boulder, CO

(Where’s it’s about 40 degrees F/4C and cloudy)