Steen writes:

Regarding Dickson’s pick of the week on TWiV 537 (starting at 1:29:02): it looks like leafhoppers (Cicadellidae) are closely related to but distinct from treehoppers (Membracidae).

As briefly noted in the National Geographic piece, treehoppers transmit fewer plant viruses: two are known, tomato pseudo-curly top virus and grapevine red blotch virus. Both are ssDNA geminiviruses, in the family which you featured on TWiV 512 (with Anne Simon).

Leafhoppers also transmit several economically important geminiviruses (see the ICTV family profile), as well as other viruses such as the reovirus featured in the paper and cover image that Dickson described.

Thanks to Dickson for excellent back-to-back picks!

Pedantically yours,


p.s. To be a bit more explicit (no need to read this on-air), the NatGeo piece was on treehoppers but Dickson said “leafhoppers” at the start. Everything else he said was valid, but the connection between the NatGeo piece and the PLOS Pathogens article is not quite as direct as he made it sound.

Patrick writes:

Hello TWIV-ers!

I just wanted to drop a note in to push back against Dickson’s comments about homeschooled students in your recent episode. He mentioned that homeschooling undermines the country’s intellectual capacity, keeps students from getting involved in debates, and isolates people. I take exception to his comments because I was homeschooled from 4th grade through high school. I was not isolated; I participated in numerous activities including a homeschooled speech and debate league where I engaged in debates and considered other ideas. I was not intellectually stunted; I got scholarships for debate and academics to attend a liberal arts school Concordia University, and from there I have gone to Baylor University where I am working on a molecular biology PhD. Through this process I have met many successful homeschooled students in a variety of fields (Many of the highest ranked collegiate debaters in the country are homeschooled, including several who were on Concordia’s team).

Moving from anecdote to data, this USA today article gives a nice study of a Texas A&M study on outcomes of homeschooled students in college. It seems we do quite well.

I understand that there are people who use homeschooling as a method to silo students in intellectual conformity, and it is particularly pernicious when people homeschool their children in order to not vaccinate them. I just wanted to point out that this does not describe most homeschooled students and the comments implying that homeschooling imparts a lack of exposure to other ideas or intellectual rigor are inaccurate. I trust that Dickson does not make these comments out of any ill will but perhaps just sees the bad side of this practice when it is used as an excuse for anti-vaxxers. I have great respect for you all and I love the show, I really wish I were writing to tell you about how my research deals with one of your episodes instead of this. I hope you’ll excuse the long email and believe me when I say it is not in an angry tone (certainly not as angry as all those people who complain about the weather updates!), I just wanted to inform you that there are many good and accomplished homeschooled students out there who are vaccinated and enjoy a rigorous intellectual debate.

Oh, and here in Waco it is -3ºC (27 ºF), and will swing all the way back to 24ºC (75 ºF) by Friday. Texas weather is weird.


Steve writes:

You were talking about backing up podcasts and then I see this:

Delete Never: The Digital Hoarders Who Collect Tumblrs, Medieval

Manuscripts, and Terabytes of Text Files

Mike writes:

Dear TWiV hosts,

I would like to follow up on the your discussion of the vaccine perspectives for the flavivirus NS1 protein. I was actively involved in studying protective properties of the tick-borne encephalitis virus (TBEV) NS1 protein during my PhD thesis work at Chumakov Institute of Poliomyelitis and Viral Encephalitides in Moscow, Russia. In 1994, Dr. John Stephenson  and colleagues (then from the PHLS Centre for Applied Microbiology and Research in Salisbury, UK) demonstrated that replication-defective adenovirus vector (hello, Dr. Spindler!) expressing the TBEV NS1 elicits protection against lethal TBEV in mice (link). Later this project had been further developed by my mentor, Dr. Andrey Timofeev in collaboration with Dr. Stephenson.

The results of this project demonstrated that:

  1. Plasmid carrying NS1 gene protects against lethal TBEV challenge in the mouse model.
  2. Heterologous vaccination with the vaccinia virus vector (hello, Dr. Kondit!) carrying NS1 gene and the plasmid carrying NS1 gene shows protection against TBEV challenge in the mouse model.
  3. Peptide from NS1 protein elicits partial protection against TBEV challenge in mice that is mediated by the anti-NS1 antibodies.

We did not look at any vascular pathology in immunized animals, but no side effects of immunization were ever observed. However, mice are not the most eloquent conversationalists, thus our conclusions regarding mouse health were based on superficial observations.

I provided a short list of the publications related to this project. My impact was very modest at best, but since then flaviviruses have become the most amazing viruses for me.

(Display the 10 citations in PubMed)

You also discussed the complexity of the vascular endothelium. I had a privilege to study the role of cytomegalovirus and obesity in the mouse model of endothelial dysfunction at LSU Health Sciences Center in Shreveport, LA under the guidance of Dr. Karen Stokes. Interactions between vascular endothelium, white blood cells, platelets, and the roles of immune responses in these interactions are indeed exquisitely intricate and complex. I hope that the group of Dr. Harris will be able to fully elucidate mechanisms underlying NS1-induced endothelial permeability.

Lastly, thank you very much for your podcasts – they are a great source for my continuous education as the microbiology instructor. By the way, you don’t have to say my full Russian name when you read this letter – I have been called Mike for all 13+ years in the US. In case you are interested, I attached the audio file with the proper Russian pronunciation of my first name.

Link to pronunciation:

Yours sincerely,


Mikhail “Mike” Khoretonenko, PhD

Assistant Professor

Department of Biology

Lakeland Community College

Kirtland, OH

Mike writes:

Dear TWiV hosts,

This is a follow up to a follow up I sent in recently. First, I would like to apologize for misspelling the last name of Dr. Condit. Here, I correct myself. I also would like to submit a listener’s pick due to the growing agitation around the biopic dedicated to Queen, namely “Bohemian Rhapsody” – the song “Post-doc Me Now“. Hope you like it.



Mikhail “Mike” Khoretonenko, PhD

Andrew writes;
Hello TWIV,

I am a new listener that found your podcast shortly after beginning a postdoc researching RNA viruses. Since my background is not virology your podcast has helped better my understanding of all things viruses, thank you. After listening to episode 535 I was thinking that flavi NS1 may be a useful tool to permeate specific cells, maybe even for drug targeting. I’m curious what you think of this idea and the best available methods to target infected cells in general. Thanks again.



PS, today it’s 18 centigrade with fairly clear skies.

Anthony writes:

Bob writes:

The U.S. is funding dangerous experiments it doesn’t want you to know about

Listen to your podcast every week.

Regards, Bob

Ryan writes:

Hey Vincent and the Twiv Crew I recommend watching the Jeff Holiday rants because he’s been trying to get non-biology majors to understand the dangers of listening to Andrew Wakefield and his political supporters like Larry Cook in the midst of the Measles outbreak.

In another series of Videos Jeff Holiday give us a warning as far back as 2018 that the measles outbreak would end up as a national issue in the USA. In that Video Jeff Holiday named Del Bigtree and Infowars for sparking the Measles outbreak but at the time of the rant Jeff Holiday didn’t have the exact victim numbers of the 2019 outbreak except he accuses Infowars for making the Anti-Vaxx Movement a political issue as far back as 2018.

Ian writes:

Measles and antibiotics. Not in America.

I note that antibiotics are useful in treatment of measles.

They do not of course affect the virus.

But, a substantial fraction of people infected by measles who would die

or be blinded without access to healthcare will be ‘fine’ with access to it.

Two vitamin A tablets reduces mortality by 50%, as well as morbidities –

blindness. Oral rehydration and antibiotics for secondary infections

greatly help too.

It is important to stress that viruses cannot be directly targeted by

antibiotics, but unless the death is directly due to the virus (Rabies)

saying it is ‘untreatable’ – or that good healthcare post infection does

not matter is going too far. The CDC notes that the MMR

vaccine is also useful as post-exposure prophylaxis up to 72 hours after


From a Scotland experiencing perhaps its first sunset of the year.


Thanks again for the tremendous resource.

Anthony writes:

On TWiV 537 you mentioned anti-vax Facebook posts going viral. Was that meant to be a joke?

Breaking up Facebook won’t accomplish anything. The problem is that people in general are stupid and electronic media gives them infinite and instantaneous ways to leverage that.


When you’re young, you look at television and think, There’s a conspiracy. The networks have conspired to dumb us down. But when you get a little older, you realize that’s not true. The networks are in business to give people exactly what they want. That’s a far more depressing thought. …


Steve Jobs

# # #

Education and communication won’t help curtail the anti-vaccine movement, either. What’s needed is litigation, prosecution and incarceration. I’d guess that since the Model T, people knew that drinking and driving were a bad mix. They still did it. Bartenders and hosts knew that it was wrong to give alcohol to someone visibly inebriated. They still did it. When people sued and juries handed out big sums, bartenders and hosts learned responsibility. When drunks were apprehended, fined, licenses revoked and — in the case of accidents — jailed, drunk driving diminished.

For the edges of anti-vaxxers, marketing will work. Those thinking it trendy to let their children get sick can be convinced by advertising that it’s really not fashionable. The PETA anti-fur ads are an example.