Jennie writes:

Hi TWiVers,

I was glad that you discussed the March for Science on TWiV 426. A strong public show of support for science is critical. As a follow up, you and your listeners may be interested in this blog post by a doctoral student in Disability Studies.

She raises some legitimate questions about the March, including the description of science as apolitical. One major criticism related to the intersection of the March and disability issues has been partially addressed by an updated diversity statement from March organizers. I think there important issues to consider, and grappling with them will make the March stronger. I am hoping for an accessible satellite March in my city so I can participate!



Christian writes:

Hi TWIVome,

Some comments to TWIV 426, although these are not really scientific, but touching the current political situation:

The alternative National park service twitter account was run by employees of the National Park Service (after the administration silenced the official account), but they have handed over the account to journalists and activists due to immense pressure to find the persons behind it. There is an interesting article on this:

There is another interesting rogue twitter account, apparently from inside the White House (although there is of course no proof for that for obvious reasons):

For everybody planning to do something similar, here is an interesting description of how to set up, maintain and operate a secret twitter account:

For scientists not participating in politics, there are now also scientists who think about running in politics. One of the more well known is probably Michael B. Eisen (one of the co-founders of PLoS): and .

I am a listener for quite some time and although I am a post-doc biochemist working in cancer research I like hearing podcasts from the quite a lot. Staying interested in broad science is important for scientists in my view, as you otherwise would narrow down too much. Thanks for all your effort.

If I am the 27th email in the current contest (on the Emerging Infections book), I would be delighted to add this to my science reading list.

The weather here in Dresden, Germany is quite wintery with temperature of -2°C (around 28F) and it has been snowing all day now.

best wishes,


Anthony writes:

Out of print no longer means unavailable.  Buying each book used Online for less than $5 total is a lot easier than trying to arrange an inter-library loan — for both me and for the librarian who would have to search and submit the request.

I’ve not seen Papers in Biochemical Genetics, but from the raves in TWiV, perhaps a separate — stand-alone — podcast discussing each paper might be worth considering.  Maybe it could be organized to be a course on iTunes U?




Trudy writes:

Dear TWiVoids,

I’m writing this email in response to your discussion on TWiV 426 about whether there are any viruses that require an intermediate host for replication.  

My gut answer would be “no”, but I can’t help but speculate a little about the Bracovirus replication cycle. The story of the relationship between the Bracovirus and the Braconid parasitoid wasp is told beautifully by Rich Condit on TWiV 179, and I believe there is another discussion about this virus on a more recent episode, but I can’t remember which one.

The relationship is a unique symbiosis which has existed for about 100 million years.  Genetic analysis suggests that at some point the virus infected the wasps, integrated into the wasp’s genome, and since then is only vertically transmitted to offspring as an integrated provirus.  The virus only replicates in specific cells of the ovary called the calyx cells, and does so only in response to hormonal signals.  The viral replication cycle consists of amplification of viral DNA, virion formation and packaging.  The viral genome package in the particles is composed of multiple dsDNA circles, but no structural proteins, although it does harbor immunosuppressive genes.  Once the packaging has occurred, these calyx cells are lysed and the virions accumulate in the calyx lumen to form calyx fluid.  Together, the wasp and the virus parasitize a lepidopteran host caterpillar.  When the wasp egg is injected into the body cavity of the caterpillar along with the calyx fluid, so are the viral particles.  Once inside the caterpillar, the virus doesn’t really replicate, but it suppresses the caterpillar’s immune system.  If it didn’t suppress the caterpillar’s immune system, the wasp egg would be engulfed by the caterpillar’s phagocytes, so the co-infection of the caterpillar with the egg and the virus together allows for survival of the wasp egg in the caterpillar, leading to hatching and complete development of the immature wasp in the caterpillar. Additionally, genes expressed by the virus in the parasitized host alter host development and metabolism in order to benefit the growth and survival of the parasitoid larva.

So MAYBE this could be one example of a virus that infects one host for one reason (to replicate), and infects another host for another reason (to help its symbiont).

Just a thought.

Kind Regards,


Rich writes:

Dr. Racaniello…. Thank you for your comments regarding the Trump/Kennedy meeting, discussed in TWIV 424. It was helpful because I was so angered when I read about the meeting and then the “tweets” that followed, I began to question my sanity. All of this has direct implications for my practice of Dentistry. I deal with the concepts of contagious disease on a daily basis. Flu, measles, pertussis, and the rest are a big deal when working a few inches away from patient and contagion can go both ways. Anti-Vax is a big deal here in California. One never knows what one has been exposed to, as was the case at Disneyland.

A special thanks to Professor Spindler for her very complete summary of Wakefield’s insult to science and public health. It would be great to publish on the blog. More fire power as shaped ignorance tries to take control.

Thank you to you and the TWIV TEAM and ASM for your remarkable efforts in communication.


Casey writes:

Hello! I would love to win the copy of Infections of Leisure. Hope I am #17!

Also, I wanted to send you a personalized Thank You note for the TWIV mug that you sent me a couple weeks ago for entering the limerick contest. I absolutely love it.  In fact, I can’t bring myself to use it at all because I can’t stand the thought of forever tainting it with coffee stains! So it is currently sitting on my highest cupboard shelf so I can admire it.



Megan writes:

Hi Vincent,

I think the infections of leisure sounds awesome! Am I number 17?

(I haven’t been emailing, because I was CERTAIN someone would beat me to it!)

I had the great fortune of being on TWiV 333 at Vanderbilt and continue to be a dedicated listener, even as I have moved on to the Children’s Hospital of Pittsburgh for my residency in Pediatrics. I’d love a copy of this text!

Betsy writes:

Unfinished Sonnet* for a book contest

Seattle’s overcast and dark these days

The high has been ‘bout 5 this whole, dark week

(and, yes, the “5” is temp in centigrade)

The gloomy weather makes me want to seek

Greater knowledge in virology

To understand just what my brother does

He researches that pesky HIV

But I don’t always understand because

I haven’t taken science since the Aughts,

And since return to such was not predicted,

Until revisiting with TWIV I’ve not

Applied myself, but now I’m quite infected addicted(?)

And nothing would give me as much pleasure

As reading about Infections of Leisure.


Hi, TWIVering aspens!

I’m Betsy, writing in for the book. Am I too late to win?

Thank you for the podcast. I’ve been listening for a while now, on the bus or at work, and I think I am learning a lot. My phone is littered with open tabs from googling things throughout the podcast. Anyway, thanks a lot for all your work! I always look forward to the next edition.



*I would have worked out the kinks, but was afraid I was running out of time. Feel free to read “wasn’t” as a single, indistinguishable syllable to navigate line 10, or make any other edits you see fit!  Hahahaha.

Tom writes:

A photo of a child holding a protest sign, purportedly taken at the January 21, 2017 Women’s March in Washington D.C.

The sign reads:

What do we Want?


When do we Want it?


— Tom in Austin

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