Dalan writes:

Dear Professors Racaniello, Dove, Condit and Spindler,

Firstly, I just wanted to say thank you for highlighting our recent paper on morbilliviruses on last week’s show – ‘Morbillivirus had a little lamb’. It was great to hear other virologists discussing our work and the importance of the research. I’m also really glad you liked the quantitative fusion assay – although I’m sorry I didn’t explain it better! I just wanted to get in touch to address a couple of the interesting points you raised.

  • You mentioned that measles virus is thought to have evolved from an ancestor of the now eradicated rinderpest virus. Phylogenetic analysis of this genus fully supports this hypothesis. What’s really interesting is that following the eradication of rinderpest there is presumably no longer any morbillivirus herd immunity in cattle. However, these animals are often co-grazed with PPRV-susceptible sheep and goats. What we are now seeing, in various serological studies, is significant PPRV sero-positivity in cattle (20% or higher in some populations). Although there is little evidence for clinical disease in these animals, I think this raises important questions about how long it takes viruses to emerge as pathogens in so-called “vacated ecological niches” – I’d be really interested to hear your thoughts on this topic.
  • We’ve also done a little bit more sequence analysis on old rinderpest virus isolates and realised that one of the old vaccine strains that was adapted to rabbits and eggs also has a mutation at the same position, 191, in its Haemagglutin protein, as we identified in our study. I think this is pretty cool as it supports the idea of host-specific adaptation at this position.
  • We don’t have BSL4 (or CAT4/ACDP4 as we call it in the UK) at Pirbright, although we do have BSL3, where we do a lot of influenza work. In the UK we use a separate containment system for animal pathogens, called the Specified Animal Pathogens Order (SAPO). We do handle the top level SAPO pathogens at The Pirbright Institute – for instance PPRV, FMDV and ASFV, all of which you mentioned in your show.

I realise you won’t have time to read any of this out on the show but thought I’d get in touch.

Thanks to you all for your continued efforts in supporting the international virology community!

Warm regards,

Dalan Bailey

Margot writes:


I am in my early thirties and graduated from AZ State University with an undergraduate degree in microbiology and a passion for virology. I have decided to go back to school for medical laboratory science and then an MPH emphasis epidemiology. I plan to apply someday for the CDC Epidemic Intelligence Service. Your show keeps me going while I get the rest of my schooling in order. I love your show and have been going through the archive trying to catch up.

My question has to do with Ebola nomenclature. I have written on Ebola for various papers as an undergraduate and have never heard of Makona before. I tried looking up information on Ebola nomenclature but it didn’t help elucidate Ebola Makona for me. Could you please talk about Ebola nomenclature? How does Makona fit in with Reston, Sudan, tai forest, Zaire, and Bundibugyo strains? Thanks in advance.

Anthony writes:

In 2019, cultural divides between science and art will cease to exist

“We understand now that the arts and sciences are the subjective and objective poles of the same great human enterprise, that there is only one world out there and we have to view it with an ever-curious and ever broadening mind”


Ken writes:

TWIV+TWIM+TWIP+TWiEVO+Immune should hit 1000 this year

The total is about 935. Maybe for the 1000th TWIX you could do a joint podcast across some or all of the podcasts.

Thanks for all the great podcasts,


Tomer writes:

Hello twivosophers,

My name is Tomer Granot, and I’m currently a scientist at a biotech company. In a previous life, as a postdoc at Columbia University in 2017 (Donna Farber lab), I had a paper that was published in Immunity. We then submitted a cover image, which was not accepted by the journal. This lead me to realize that there are probably thousands of interesting, thought-provoking science journal covers that never got published, and were ultimately tossed away into personal file obscurity. My aim is to change this by creating a website that brings these rejected covers to light. I will call it “Uncovered science: Research Journal Covers that never made it..”

The reason I am contacting you is that I was hoping you have some good suggestions for a platform for this website. I was thinking about Squarespace, but perhaps you have some other ideas. If I am able to get this website going, I would also appreciate if you could send me any failed cover art from your labs..

Thanks for your time,


P.S. I’ve attached a grainy picture of the failed cover we made for Immunity.

Anonymous writes:

Hi TWIV team,

Greetings from Southern California, where we are currently experiencing consistent temperatures of 15-20°C with a bit of rain here and there.

I have been listening to TWIV for over the past six months and have found it to be intensely fascinating, entertaining and one of my highlights of the week. I think there are few places to listen to a diverse array of topics in virology and also hear the input, opinions and perspectives of a variety of knowledge people.  I was also excited to discover and start listening to the Immune podcasts as well.

TWIV 527 was personally relevant to me, having suffered with chronic gastrointestinal (from stomach to large intestine) dysmotility all my life and which only continues to worsen and become more unpredictable. I found it comforting to know that there is active research  that challenges the common doctor’s office diagnosis of dysmotility as just something caused by “stress” and that is, essentially, that patient’s own doing.

The paper by White et. al. featured on TWIV 527 and countless other studies about immunity, infection and dysmotility provide an even stronger foundation for better diagnostics and therapeutic innovations, but I feel that looking for immunological causes of dysmotility disorders will be neither readily nor quickly utilized and accepted in the clinic, especially until human studies have been done. Therapy targeting the immune system will most likely carry many unknown side effects and risks, require more monitoring by clinicians well-versed in immunotherapy and a considerable price. I am curious to know your thoughts about how successful immunological dysmotility therapy could be if effective therapies can be developed: would it be accessible to many people? Will we still need to look for other, more practical therapies? Will we need to focus more on identifying the culprit viruses and pathogens, and develop measures to prevent subsequent effects on gastric motility? Might the development of gastric dysmotility disorders depend on the individual’s immune response to infection since most of us are likely to experience the same infections from the culprit pathogens?  For instance, CAR-T cells were a notable landmark in cancer immunotherapy, but few people (let alone insurance companies) would be able to afford such care.

Thanks for your wonderful podcasts and keep up the great work . Your work has been a great complement to my academic career and development as a scientist, and is something I aspire to.

Margot writes:



I love your podcast! I was listening to your talk with Dr. Hotez. It got me thinking. You should check out the Alan Alda Center for Communicating Science. Perhaps something like that can be started at other institutions. Also, I think you might be interested in AZ State University. I know it may be counterintuitive but ASU is a great university for community engagement. There is a department called the School for the Future of Innovation in Society where science communication by/from scientists and the issues you raise might find a good home. Granted I got my undergraduate microbiology degree and my masters from ASU.

Thanks again for an amazing podcast!