Justin writes:

FDA approves first-of-its-kind product for the treatment of melanoma


Stephanie writes:

Can I offer a snippet for today?  I have an influenza paper to share! This paper is a PLOS pathogens paper by Paquette et al., 2015 and is entitled ‘Influenza Transmission in the Mother-Infant Dyad Leads to Severe Disease, Mammary Gland Infection, and Pathogenesis by Regulating Host Responses’. Right up my alley! To be honest, if this had been on posted on pubmed prior to my TWiV, this would have absolutely been the paper I would have chosen!

My most interesting takeaways from this paper

(1) The bidirectional transmission of influenza from infant-mother and mother-infant via respiratory route AND mammary (!) route.

(2) Mammary gland cells from ferrets and breast cells from humans were permissible to influenza. 

(3) This study also suggests that influenza that can transmitted to infant ferrets through the mammary gland. However, this study used direct inoculation of the mammary gland to prove this. Since it is not the mammary gland that becomes inoculated with influenza first, I remain skeptical that in a natural infection, mammary gland alone would cause the severity of disease they saw. However, I definitely think the mammary gland could contribute. But then, neutralizing antibodies and other neutralizing factors in milk could prevent virus transmission, particularly at low titers. Regardless, the mere fact that the mammary gland could contribute to infection is alarming and must be considered in disease pathogenesis.​

I believe that studying virus transmission via milk is imperative to human health. We must understand this mechanism. The HIV milk transmission model is well established. However, there is such a paucity of info for other viruses.

Influenza Transmission in the Mother-Infant Dyad Leads to Severe Disease, Mammary Gland Infection, and Pathogenesis by Regulating Host Responses http://www.ncbi.nlm.nih.gov/pubmed/26448646

Lauriel writes:

Hello TWiVers,

I’m a fifth year graduate student at Oregon Health and Science University in the Molecular Microbiology and Immunology department and first, I’d like to say thank you to Dr Racaniello for accepting our invitation to be the keynote speaker at our upcoming departmental retreat. We’re very excited for your visit and talk, although I’m sorry to have to tell you that the retreat is taking place at the World Forestry Center where you will be forced to look at plants all day.

I also wanted to say thank you for the interview with Dr High (episode 350). My current work focuses on Adeno-associated virus as a vector for gene therapy and it makes me happy whenever I hear a shout out on TWiV about how successful this little virus has been. Which brings me to a point I wanted to add to the on-going “gain-of-function” discussion (and I apologize if this was mentioned before and I missed it), but I find it funny that the main focus in the AAV field right now is all about gain-of-function. The last American gene therapy meeting was filled with talks about using different techniques to create new AAV vectors with novel properties, mostly focused on infecting specific tissue types or avoiding neutralizing antibodies. A standard protocol in the field is to create a library of different AAV capsid mutants (point mutations, chimeras, peptide insertions, etc) and do ‘directed evolution’ or bio-panning to isolate mutants that have a higher tropism for the cell type you want to target in vivo (see Bartel et al. “Directed evolution of novel adeno-associated viruses for therapeutic gene delivery.”http://www.nature.com/gt/journal/v19/n6/full/gt201220a.html for a recent review). I’d imagine that if someone tried this with flu, the backlash would be harsh. I guess the ban on gain-of-function doesn’t apply to AAV since it’s still considered non-pathogenic and most people are already antibody positive for it?

Speaking of how common AAV is in the population, I think Dr Racaniello will be interested to know that AAV has been proposed as a commensal virus of mammals (http://online.liebertpub.com/doi/abs/10.1089/hum.2005.16.401). AAV is known to lower titers of its pathogenic helper viruses in culture and epidemiological evidence implicates AAV as a negative risk factor for developing cervical cancer from HPV infection.

Thank you all so much for the TWiX! In my lab, we’re pro-virus all the time, trying to infect people and bypass the immune system, so I really enjoy learning about the “other side” of virology. I love everything about your podcasts, from the great journal article discussions to the on-going conversations about the plight of post-docs and gain-of-function studies to the weather.  Right now in Portland it’s 63oF/17oC, sunny with scattered clouds, and winds at 2mph. I’d say it’s a beautiful fall day except this year has been our warmest and driest we’ve had for a long time. The changing weather is alarming, especially for those of us with urban gardens; at least all of our peppers did well this year.


Karen writes:

As we move into flu season and the fear of vaccines again ramps up,  I have a question that has come up in general conversation, and I don’t know how to answer.

If flumist is a live attenuated virus that sheds, though it is not a danger to immuno intact people, could it pose a risk to the immunocompromised? For example we generally avoid getting the flumist if we are going to have contact with those isolated in a hospital and undergoing immunosuppression before transplant, but is it safe to be around those who are out in the general public and undergoing “regular” chemotherapy for cancer treatment? Another example given was someone taking “immunosuppressants for sarcoidosis”.

Any thoughts or expertise you could share for us lay people out here fighting the good fight for vaccines would be greatly appreciated. Please excuse any inaccuracies in my questions, I’m not an expert just an enthusiast.

Many thanks,

Stephanie writes:

Good afternoon,

  I have appreciated your podcasts over the past years and wondered if you have an episode or article addressing the theory that the HIV outbreak in humans may have been facilitated by use of a polio vaccine derived from monkey kidneys. I have only ever heard the theory of HIV originating from some source of bushmeat and spreading rapidly through sexual contact in an urbanized setting to make its widespread debut on the world scene.

Thank you for your work.



Jackson writes:

Dear Twivers,

I was on Facebook and saw IFLscience’s post about four types of antivaxers and methods to change their minds about vaccines. I followed IFLSciences links to the original article and thought it was an interesting article about antivaxer attitudes and a nice addition to the paper in PNAS discussed on episode 349. http://bbs.sagepub.com/content/2/1/61.full  The article is open access and comes complete with tweets for attention spans too short for abstracts. Thanks for the great podcasts I love listening to them while I’m waiting for gels to run in lab or in the gym. Its 54 F, 12 C, 285 K and drizzly here in College Park MD.

Original IFLscience source http://www.iflscience.com/health-and-medicine/four-types-non-vaccinators

Jennie writes:

The best listener pick ever: the people of Sierra Leone celebrate being declared Ebola free. Check out the serious dance moves, especially from Ebola Treatment Center staff!


Thanks for all you do! Cheers,


Peter writes:

Dear TWIV hosts (no time or ability to come up with a new creative way to address you),

The edX course Epidemics from Hong Kong University might be of interest to your listeners.


It’s not too late, since even the course started on Sep. 15th, the first graded quizzes are not due until Nov. 24th.  Enough time to catch up in case, one is interested in a certificate.

Week 1 features a Panel discussion from Oct. 28, 2014 with Peter Piot, originally part of the first time this course run on edX last year.

Speaking of MOOCs, is there any schedule for new iterations of “How Viruses Cause Disease” and/or “Virology I: How Viruses Work” on Coursera?

All the best from Inchon (Korea), where it is currently (Oct. 5th, 2.00 pm local time) 22°C, mostly sunny, humidity 33%, wind WNW 4 mps, pressure 1,023 mbar, UV Index 6 or in short a perfect fall day,