Nick writes:

Just finished listening to TWIV on the way to work. You guys did a great job on the episode.

Here is a good article on the adjuvant narcolepsy issue. (,0,3842221,full.story) there are some genetic factors that are being looked at. Which is really important in this homogenous population.

Just in case you’re interested…there were some critiques recently of the CDC study methods for estimating vaccine effectiveness. The authors responded and got into epidemiology of what they did and why. (


Diane writes:

Hi Dr. R et al,

Thank you so much for your amazing episode on the flu vaccine. You answered all my questions and more, and it really helped.

Thanks again!

Clifton writes:

Hello TWiV team,

I just listened to TWiV 217, and I have a question.

Regarding efficacy of the flu vaccine, Alan pointed out that the Polio vaccine is given three times, but flu shots are only once. After getting the flu in 1990, I have not missed a year since. I know the WHO changes the strains often due to mutating strains, but apparently I have received several years of vaccine for the A/California/7/2009 (H1N1)pdm09-like virus. And even when the strains are not good matches, the CDC claims there is some benefit of the vaccine. Has anyone ever checked to see if the efficacy increases for people who get their flu shot every year? If not, would you think there may be an increased benefit from getting vaccinated every year? I know I may be asking you to speculate.

For the benefit of your demographics, I have a PhD in systems engineering working for the federal government (not health related). But I do have an interest in virology since like you, viruses make me sick.


Amanda writes:

Dearest TWiVonians,

I am a recent convert to the TWiX universe, and I have to say I love your podcasts. They make my walk to/from the lab a treat, and turn me onto research I might otherwise have missed. I am currently a postdoc at Dalhousie University, in Halifax (Nova Scotia, Canada). Currently I am working on Influenza and Strep pneumo. I previously completed my PhD at the University of Saskatchewan (pronounced Sis-cat-chew-in) in Vaccine Development. I have to say, whenever you mention the weather being cold, I snicker a little thinking about growing up in northern Saskatchewan with -35 to 40 degree celcius winters with -40 to 48 degree windchills (note, at -40 celcius and ferinheight are equal so these numbers should mean about the same to you as they do to me). Today in Halifax it is a balmy -10 degrees celcius, with a -19 windchill (14/-2 F). Almost T-shirt weather!

Now, to my point. While I lean towards viruses being not alive, I have found a compelling case for scientists to call them alive, regardless of personal preference. I found myself chatting with my seat-mate on a plane over christmas, and the topic turned to vaccines, in particular the Influenza vaccine. She mentioned her fear of having virus introduced into her body. I assured her it was inactivated virus. And she said “but it’s still live virus”. I explained that ‘inactivated’ means dead in this case, the virus cannot replicate and is only there to induce an immune response so that when your body next encounters that strain of Influenza, it will react quickly since it ‘remembers’ that strain. This conversation concerned me, so I began asking non-scientist friends and family what they thought the influenza vaccine was made up of, and what they thought the term ‘inactivated’ means. The vast majority of those I talked to did not realize that inactivated means essentially ‘dead’ in this case, and some even thought the term ‘inactivated’ was a bit suspicious and vague.

So, while us microbiologist-types can sit and argue about viruses being alive or not, for the sake of the general public and their fear of vaccines, it might be better for us to use the term alive for infectious virus and dead for non-infectious.

I would also like to submit a listener pick of the week. My friend Patricia knows how hard it can be for me to switch from experiment mode to writing mode, so she turned me on to this website:

Written? Kitten!

Basically, every X number of words you write (customizable), it will show you a delightful kitten picture.

Amanda, PhD

Post-Doctoral Fellow

Canadian Center for Vaccinology

Jonas writes:

Dear fellow scientists,

Regarding your discussion on narcolepsy and the 2009 influenza:

A report from 2011 showed a similar increase in narcolepsy in China during the 2009 H1N1 pandemic, this despite only very few of the newly diagnosed patients being vaccinated against the flu.

A recent report from South Korea (where they used MF59 and not AS03 as an adjuvant) showed a decrease in newly reported cases of narcolepsy after the influenza vaccine campaign commenced.

So there could other causes of increased narcolepsy besides AS03, and as always: More studies are needed.

An unrelated, but for me funny, coincidence with my first comment to TWIV:

I was born in Linköping, Sweden and lived there for 18 years before moving to Stockholm. (Regarding Dr. Despommier’s planned travel to Linköping).

Best Regards, Jonas


Jonas Söderholm, PhD

Department of Infectious diseases

Virologiska Laboratoriet

University of Gothenburg


Jeff writes:

First let me say I enjoy the podcast. It makes the San Francisco Bay Area commute entertaining, educational, and less stressful. I did want to point out one correction on TWIV 217. You can actually challenge people with influenza in the context of a clinical trial at a company in the UK called Retroscreen ( They also do challenges with RSV and Rhino virus. I have seen Dr Rob Lambkin-Williams present at a conference on the conduct of these studies and think an interview with him would be of interest to the TWIV audience.



Eric writes:

Dear Vincent

As I do for all TWIV I greatly enjoyed the discussion of the RacPyV polyomavirus that Pat Pesavento from UC Davis discovered in raccoon brain cancers. I hope Pat will be able to discuss her work on TWIV.

The discussion with Stuart Firestein about ignorance in science also reminded me of the quote I used as intro to my thesis: “Education is the progressive discovery of our ignorance” by historian Will Durant

I though you might also enjoy the virus-like toys below. Kinda like the plant seeds pic for TWIV 215. Like real viruses they can spring open into different shapes and clamp shut into tight spheres.

Still trying to get my kids to understand that viruses are neither dead nor alive but like zombies need to feed on living tissues. They get great amusement from loudly announcing that their daddy studies viruses in poo and pointing out interesting samples on the streets.


Eric Delwart

Lindsay writes:

Dear Vincent and colleagues,

I have three things I wanted to talk about. First, I’ve only recently discovered your collection of TWi podcasts and am slowly but surely working my way through them. I just listened to the special TWiV with Stuart Firestein and was reminded of the importance of mentors. An advanced degree in microbiology is my ultimate goal since I was in high school, and I would really like to find a mentor, but I’m not quite sure how to go about finding one. I apologize if this has been asked and answered already.

Second, I wanted to thank you for what is surely more than a hobby. I imagine that a lot of work, patience, and dedication goes into producing three amazing podcasts week after week. I’m currently employed as what amounts to as a valve turning, button pushing monkey and this is one of the podcasts that keeps my mind engaged day after day.

Third, if you haven’t found this already, I wanted to share a new Twitter hashtag a friend shared with me, #overlyhonestmethods. io9 has collected several gems (, and I hope you find them as amusing as I do.

Thanks again and I look forward to many more podcasts.



Marian writes:

Regarding the finding that adenovirus capsids bind Coagulation factor X:

Dr. Mark Crislip, of the Persiflagers infectious disease podcast, is constantly saying that infectious events precipitate cardiac events and has given various mechanisms to explain it. This represents yet another. Also, you mentioned that in the horseshoe crab, coagulation proteins represent a primitive adaptive immune response. Remember that Staphylococcus aureus has coagulase as an important virulence factor.

You also brought up viruses for gene transfer delivery. Poliovirus-based vectors have also been used for gene transfer.


Alexandra writes:

Dear Drs Racaniello, Despommier, Dove, Condet, and Spindler,

First, I want to thank you for the gift of this netcast, and of the sister shows TWIP and TWIM, of which I am also a fan. I discovered this show midway through my fall semester of 2012, and TWIV has been my primary relaxation and motivation. As a biology student, I would motivate myself to study for chemistry or other coursework by saying, “Finish this chapter, and you can listen to TWIV.” In the space of a month I listened to nearly 40 episodes.

Second, I have a few questions, likely naive (but you will forgive me, I hope, as I am only an undergraduate). This past fall I took a course on ecology and biodiversity, and one topic we covered was Kingdom Fungi. I am curious about viruses of fungi — I have heard a little about plant viruses (tobacco mosaic virus) but I have never heard of a fungal virus. My question is, many phyla of fungi have coenocytic hyphae – that is, the filaments that make up the bulk of the fungus have no cell walls or cell membranes. These hyphae are about one cell thick, but can be many hundreds or thousands of cells long, and in coenocytic (rather than septate) hyphae, there are no barriers between one nucleus and the next. How does this affect the viruses of fungi?

Thank you once again. I suspect I will pepper you with questions in the future, and if my questions have sometimes been answered in previous episodes, forgive me – it will probably take me a year to work my way through the entirety of your archive!



Leave a Reply

Your email address will not be published. Required fields are marked *

One comment on “TWiV 218 letters