Ken writes:

Dear TWiVerati,

Quick follow up to TWiV #491.  The “great oxidation event” is estimated to have taken place more than 2 Billion years ago (long before the radiation of vertebrates), but I am sure that there were viruses then too. . . . .

Regarding viruses in amber, there was a publication by George Poinar and Roberta Poinar on inclusions in up to 100 million year old amber that look a lot like insect polyhedrosis viruses ( and a possible trypanosomatid (Dixon might like this) as well.  

Unfortunately (as I was told by George himself), most electron microscopists are not wild about putting tree sap into their multi-million dollar microscopes (if any TWiV listeners would like to give this a try, please let me know!).

Also a shameless plug for our recent review : “Astrovirology: Viruses at Large in the Universe” in Astrobiology which discusses the evidence for REALLY ancient viruses (  The cover art by my co-author Aaron Berliner is really amazing (see attached), some of the press that picked up this article considerably less so (Google “Killer Alien Space Viruses” if you dare).  

Thanks for the wonderful podcasts!  


-Ken (procrastinating from working on my Coronavirus lecture for tomorrow morning)

Lucian writes:

Hello again, TWiVsters!

I forgot to add a couple of things:

 – the above email is in reference to TWiV #488

 – regarding your thoughts on how to test if protein made it into a human brain, I can think of 1 possibility using PET: Roland Strong’s lab at Fred Hutch, Rebecca Abergel’s lab, and Corie Ralston’s lab (both at UC Berkeley) developed a siderophore-like molecule that can complex with (89)Zr, which is visible by PET. This siderophore/Zr complex binds with high affinity to siderocalin, which can be conjugated to some other protein. The whole complex might be too large to properly represent how well or poorly the rabies protein alone would traffic into the brain, but it is an interesting means to connect imageable isotopes to protein. The paper is available at:

All the best!

Trudy writes:

Dear TWiVers,

Since you seem to be experiencing an email crisis, I felt it my responsibility to write in this week.

I recall Alan mentioning on an episode in the distant past that the presence of antibiotics in our food is a major contributor to our current antibiotic crisis.

I recently mentioned this to a veterinary friend of mine, and she disagreed with this statement, arguing that there are very strict guidelines in place for the withdrawal of drugs a certain time before animal sacrifice. Animals are tested for residues of drugs at time of sacrifice, and apparently, if residue levels are even remotely above guideline levels, the meat is not allowed to be sold and there are very steep fines involved as well.

Along the same lines, the flora found in conventionally raised beef and antibiotic-free raised beef appears to be statistically identical according to several studies. Levels of resistance is also the same and there is no consistent reduction in resistance observed by raising beef without antibiotics.

Below I have provided links for the USDA residue testing program, a couple of links related to understanding animal drug withdrawal and its effects, the Food Animal Residue Avoidance Databank (FARAD), a recent news story about the minimal impact of antibiotic use in beef on antibiotic resistance. The study is supposed to publish soon.!ut/p/a0/04_Sj9CPykssy0xPLMnMz0vMAfGjzOINAg3MDC2dDbwMDIHQ08842MTDy8_YwMRIvyDbUREAGVpTRA!!/?1dmy&current=true&urile=wcm%3Apath%3A%2Ffsis-content%2Finternet%2Fmain%2Ftopics%2Fdata-collection-and-reports%2Fchemistry%2Fresidue-chemistry

For the record, I am not on either side of this debate, just don’t know what to make of it and thought it might be some good food for thought.