MicrobeWorld App


Microbes After Hours

Click for "Microbes After Hours" videos

Featured Image

Featured Video


New from ASM Press


Join MicrobeWorld


ASM House 200X200

Subscribe via Email


TWiV 150 Letters

Mary writes:

Listening to the most recent Republican, I mean Tea Party, presidential debate, I was quite upset (for many reasons), but one of which was to listen to how Michelle Bachmann characterized the HPV vaccine as a "dangerous government injection", with the implication that it is killing young innocent girls. I am worried already about how the movie Contagion will be received by the public as another government-created virus gone amuck, and now someone else is on the national stage implying that vaccines are dangerous and unsafe. And to hear Rick Santorum's reply about why vaccines are given was also quite scary. What to do about these kind of uninformed and politically motivated public statements?


Trine Tsouderos writes:

So I was at a birthday party for a friend's daughter yesterday and she said to me, oh, I saw your facebook update and clicked on This Week in Virology and I had the podcast on while I cleaned the house. And you know, it was REALLY interesting!

She's a mom of two, works with kids with special needs, no prior interest in virology at all. And she cleaned the house to TWiV!

Person by person, you are spreading the love of science!

Nicola writes:

I am a big fan of TWiV and have been listening in for the past year or so. I thoroughly enjoyed TWiV Number 141, and listening to Matt Evans talking about the new mouse model that supports HCV entry was very exciting and an important step forward for our field. However, I wanted to make a comment on his statement that only liver hepatocytes support HCV entry to high levels, and that liver hepatocytes are the only cell type within the body that express the full complement of HCV entry factors. Not quite true! Currently there is a shift in the thinking that HCV is strictly a liver-tropic virus taking place within the field.

I'm a postdoc working at the University of Birmingham, UK, who started working on HCV just over a year ago. I have been looking at the neurological symptoms associated with HCV in many infected individuals, and the focus of my work is to see whether these symptoms are due to direct viral infection of cells of the brain.

Recently, several groups, including us (details below), reported that brain derived neuroepithelioma cells possess all of the HCV receptors at similar levels to the hepatoma cell lines commonly used to grow HCV. Furthermore, these cells supported HCV entry at levels comparable to hepatoma cells (and even in some cases, higher).

Matt suggested that extrahepatic replication of HCV is controversial; however, this finding is not and has been validated by at least two HCV labs. So - maybe HCV entry is not totally restricted to hepatocytes. Indeed, it suggests that there may not be a ‘liver factor’ that defines HCV infection.

Work on HCV is really in its infancy, it has only been possible to grow the virus in culture since 2005. Every day we find out new and exciting things about this important virus, and partially thanks to Matt’s work, the view that HCV is restricted to hepatocytes is being superseded.

Finally, I'd like to thank you, Rich, Dick and Alan for making virology so accessible to so many people through TWiV. The podcast also makes it really easy for people like me to keep up to date with what is going on in the whole field of virology. I do not want this e-mail to sound like a criticism of your podcast- we here at Birmingham are avid fans!

Best wishes,



1) Fletcher et al, 2010-Hepatitis C virus infection of neuroepithelioma cell lines. Gastroenterology 2010 Oct;139:1365-74.

2) Lindenbach BD, 2010-New cell culture models of hepatitis C virus entry, replication, and virus production. Gastroenterology. 2010 Oct;139(4):1090-3.

3) Bürgel et al., 2010-Hepatitis C virus enters human peripheral neuroblastoma cells - evidence for extra-hepatic cells sustaining hepatitis C virus penetration. J Viral Hepat. 2010 Jun 23. [Epub ahead of print]

Dr. Nicola Fletcher

HCV Research Group,

Institute of Biomedical Research,

University of Birmingham, Birmingham UK

Garren writes:

Hi Twivers

I love your shows, I listen to TWIV, TWIM, TWIP, and FIB among other science shows. Thank you for the entertainment and a special thanks for that show over at Omega Tau.

I am a farmer at the moment and I would really like a couple of shows about plant viruses and fungi.

Ok, my next request is a call for help. My wife teaches biology for a community college and we have been searching for an acceptable video on evolution suitable for college level students. The problem is that they all stink. They all suffer from one or more of the following problems... 1>political slant 2>religious slant 3>no science 4>bad science 5>boring 6>just a pretty animal show and tell, etc. The list of problems goes on. Can somebody please help my wife by recommending something competent. Please help we're desperate!!!

Thank you...

Jenny writes:

You could have a discussion on how simple is simple when it comes to explaining science/virology to a public audience. I just finished listening to TWIV#146, where a listener was asking about a "virology for dummies" resource, and I thought it must be a bit hard for scientists/researchers themselves to "dumb-down" their topics that's why we don't usually have a lot of virology or immunology or science 101 type of books that are more accessible to the public. I appreciate the Virology 101 episodes that you guys did previously, but I think those episodes are still a bit technical for the layperson. It's a tough task to accomplish, but I think there must be some golden mean to getting the science right without being too engrossed in the technical details that would usually turn off the non-science person. Just my two cents.

Stan writes:

Hello. Forgive me but I just recently started listening to your podcasts and haven’t had the opportunity to listen to all your previous episodes. I am a clinical neurologist and I find that we are moving more and more into the realm of immune modulation for the treatment of more and more chronic diseases that are autoimmune related. The latest crew of drugs that have come out are the “mab” drugs which are humanized monoclonal antibodies. The opportunistic infection progressive multifocal leukoencephalopathy (PML) which, as you know comes from a type of polyomavirus called the JC virus (or John Cunningham virus), is a potential problem with natalizumab treatment. I haven’t seen a lot of other opportunistic infections with using the current immunomodulators, but I was wondering if you could tell me if you know of other potential infections that we may be setting ourselves up for with the greater use of these types of drugs? It would be great if you could add a podcast about the viruses (and parasites) that specifically pertain to neurologic disease. The presentations in neurologic systems are particularly interesting because of many different ways that people can be affected (syphilis and neurosyphilis are excellent examples).

I love the format of your show and you and your guests are excellent examples of what we need more of in today’s media, people who actually know what they are talking about. I would also suggest adding more guest appearances with practicing clinical doctors as throwing in a few case presentations here and there are usually appreciated by all (I wouldn’t want it to get in the way of the basic science information that your show is excellent at providing, however).

Thanks again for your excellent show.

Stan, M.D.

Tallahassee, FL

Jody writes:

Hi all,

I'm catching up with old episodes of TWiV and was listening with interest to "TWiV 103: Shots with LJ Tan".

During the episode I noted several times that there are no reported side effects from the pandemic influenza vaccinations. I was wondering if you had seen this news that came out since that episode was recorded?


Statement on narcolepsy and vaccination

21 April 2011

Since August 2010, following widespread use of vaccines against influenza (H1N1) 2009, cases of narcolepsy, especially in children and adolescents, have been reported. Narcolepsy is a rare sleep disorder that causes a person to fall asleep suddenly and unexpectedly. The rates reported from Sweden, Finland and Iceland have been notably higher than those from other countries. Swedish and Finnish authorities have presented preliminary statements on their investigations in the first quarter of 2011.

This has been quite big news in Finland since the first occurrences were reported last year and almost immediately it was linked to the pandemic vaccination. As it turns out the link seems to be real, although the final Finnish NIH report is not due until end of August this year. Preliminary results seem to connect the vaccination to a genetic predisposition to narcolepsy in sections of the Scandinavian population.

There is more information available from that link above including the preliminary report. The CDC also has some information available.http://www.cdc.gov/vaccinesafety/Concerns/h1n1_narcolepsy_pandemrix.html

Vaccination rates in Finland as a rule are quite high, but any risk from vaccination, real, or not, has an impact on public health. This struck me as being particularly relevant given the discussion in Ep 103 about the vaccine safety and public perceptions. Although not on the scale of the problems from the US vaccinations in the 70's it does dent quite badly public opinion of vaccine safety.

This went through several very public rounds of confirmation and denial. I guess you caught one of the denial phases. Also the basic description of narcolepsy sounds relatively innocuous, but as it was shown in a TV documentary here several weeks ago it turned out many children suffered behavioural changes, some quite severe. In a few cases so bad they were literally removed from the home.

In closing I just want to say thanks for TWiV. I am a software engineer with no medical training, but I have a strong interest in science in general, so it is always a pleasure to listen even if some things go right over my head. Just when I think it can't get any better the next episode proves me wrong!



Anttoni writes:


A little update on the story..

-"European Medicines Agency recommends restricting use of Pandemrix" http://www.ema.europa.eu/ema/index.jsp?curl=pages/news_and_events/news/2011/07/news_detail_001312.jsp&murl=menus/news_and_events/news_and_events.jsp&mid=WC0b01ac058004d5c1&jsenabled=true

sorry about the long link..

It looks like the link between pandemrix and narcolepsy has been confirmed. Apparently the condition needs a genetic disorder that the adjuvant "activates".

I also recall that this issue was on the table on twiv 110.

What is your take on this whole thing? And how could the medical industry take into account genetic mutations when designing new drugs? Is the time of "one drug fits all" coming to a end? Is there someone looking into the effects of mutations on how drugs behave? And more importantly, will this change the way some drugs are accepted in the US without local testing if the drug has been used in another country for a long period (i recall you talking about this policy in one of your twiv:s unfortunately i can't remember which one it was..)

Thanks for all the work you do for the program! im loving every episode!


Jon writes:

First, many thanks for the trilogy of podcasts, it’s a wonderful service to humanity but in one sense I think you sell yourselves short. While you may entice a variety of students into the various fields covered in the podcasts, you might have a more dramatic effect. The slowly evolving impact of the Internet on science allows for participation by an army of interested people. It’s easy to point to SETI (http://www.seti.org/), Folding@home (http://folding.stanford.edu/) or the many other similar ways (http://en.wikipedia.org/wiki/List_of_distributed_computing_projects) to contribute unused computer processing time to science but they are not necessarily focused on your areas. I think if you mention areas that need work, you might be surprised how many people have the interest and ingenuity to help solve problems. I am specifically thinking of Cyber-Infrastructure, what used to be called supercomputing, where users can do computer related projects. But there are no doubt many other tasks that can be tackled by part-time home scientists. You might therefore note these areas and specific tasks needing to be done in the show notes. I realize that no one has extra time, except for Vincent because he apparently purchases the unused time of others. But it’s only those with the in-depth knowledge like yourselves who can identify areas that need further research so I suggest you consider this possibility. Perhaps someday you might be considered the Fathers of the Home Micro-Science Movement.

I also applaud the comments of Alan regarding Food Safety and Agriculture and the declining support. When the Chinese prefer U.S. made food and drugs because they are dependable, it would be ironic if not devastating to this country’s industry if one of our products harmed one of their citizens. Keep up the great work.

Less important for the podcast is the following. I am a Food Science PhD. known to some as Doctor Chocolate, but I now work in IT, hence some of the comments above. I work for Clemson University where in the span of five years we went from not in the game to top 100 in the world in Cluster technology (high performance computing). This is the sort of change that allows you to think of possibilities and not limitations. Also recognize that the rest of the world’s computing power is likewise continuing grow at a tremendous rate, we were just catching up to where we should be.

Thanks again.


Peter writes:

Hi Guys –

I can’t tell you how much I enjoy your show. I recommend it to all the students in my Virology class and several have commented on how much they enjoy it.

I am always behind and was listening to show #141 this morning on my daily walk. Towards the end someone inquired about the idea of interfering with the geometry of icosahedral capsids as a therapeutic strategy. The New Statesman article they referenced refers to the work of Reidun Twarock, a mathematician from York. Reidun and her colleague from Leeds, Peter Stockley have actually organized a meeting called “Mathematical Virology” which brings together virologists, mathematicians, and physicists to talk about mathematical principles in virus assembly. I’ve attended a few of them and it is a very thought provoking meeting.

On the topic of inhibition of assembly I wanted to point out the work of Adam Zlotnick on HBV and Mike Summers on HIV as well as the prescient comments of Don Caspar. Towards this end I’ve attached a couple of reprints that I’ve authored that touch on these topics. The JMB paper cites the Zlotnick, Summers, and Caspar papers, and the 1998 TibTek paper lays out some of the concepts behind this approach. Perhaps you could like the references.



Keep up the good work!


Peter E. Prevelige Jr.


Dept. of Microbiology

Univ. of Alabama @ Birmingham

Birmingham AL.

Stephen writes:

Hello Vincent, Dickson, Alan and Rich.

I received this email regarding a new open access journal in microbiology you may be interested to know more about (the forward is at the bottom).

I love the show and have been an avid listener since around TWiV 70 and as many before me have done I went back and started from the beginning of the podcasts. I also thouroughly enjoy TWiP and TWiM especially since I can follow both from podcast 1. It is simply a wonderful service the team are providing. Keep up the good work.

I am from the north of Ireland/UK and I am currently a veterinary medicine undergraduate. I have a particular interest in immunology, microbiology and parasites.

In TWiP, 6 I think it was, Dickson said that horses and cows both have a rumen. This was a slip of the tongue more than anything and isn't in any way microbiology related but given my field of study it made me cringe and I felt I should say. Horses are monogastric animals, and have a very small stomach for their size. Due to the fact they are continuous grazers. This is also why they lack a gall bladder as bile is continuously secreted instead of being stored. Whereas cows are ruminants. As are goats, sheep, giraffes and deer. It is okay for horses to graze with cows. Though it isn't advised to place horses with sheep. This isn't due to a possible parasite burden but because the horse may develop a hobby for chasing the sheep.

Thanks again for the wonderful network you provide.



John writes:

Dear TWIVers,

I was listening to TWIV144, and felt like I learned a lot from it, particularly the zinc finger DNA paper. I had to rewind and listen a couple times, and probably still missed a lot, since the paper and discussion dealt with some pretty in-depth molecular biology. This led me to a few questions.

a. Since they can make this zinc finger thing that will basically clobber one particular gene, and even encode it in a virus' genetic material, I wonder whether they have looked at using this to remove or inactivate the HIV provirus from infected cells. Couldn't you use this trick to make a virus that would infect T cells and inactivate the HIV lurking in their DNA? If I understand correctly that HIV is usually latent in T cells till they're activated to fight an infection, this might be useful for massively decreasing the number of T cells silently carrying the virus. It seems like this could be done to stem cells before transplantation (didn't one of your earlier guests talk about doing this to treat some kinds of blood cancers, using an oncolytic virus?), but maybe it could also be done as part of antiretroviral therapy, to decrease the number of places the virus might be hiding out and make it less likely that the virus will eventually mutate to become resistant to the drugs?

b. This led me to wonder what happens to the original T cell population of AIDS patients who go onto antiretroviral therapy after their T cell levels go down to dangerous levels. After the antivirals get the viral level down, what happens to the T cells that are carrying the provirus? When they get activated and then start producing virus, it seems like the medicine will prevent the virus reproducing, but will leave those cells around. Do the infected cells eventually get killed off by cytotoxic T cells? Do AIDS patients who start taking antiretrovirals after their T cell levels go down lose their previous immune memory, and have to get re-vaccinated for things they were previously vaccinated against or exposed to?

c. Finally, the whole discussion made me wonder where the T cells are replenished from. I've read some papers that say that that as you get older, more and more of your naive T cells come from existing naive T cells in circulation reproducing, rather than going through the thymus. But for transplant and AIDS patients, where the circulating naive T cell population is mostly gone, their bodies must somehow be changing that, so that hematopoietic stem cells make immature T cells that go through the thymus, because otherwise they wouldnt get working T cells. But I could easily be missing something, since this is far from my own field.

I'm sending along a link to a paper on how T cells are produced at different ages, and how this affects T cell receptor diversity. I'd love to hear it discussed sometime. The discussion on how aging affects the diversity of your T cell receptors seemed really interesting, in terms of effects on stuff like effectiveness of vaccines in older people, and I bet there are a lot of implications of this stuff I don't know enough to even suspect.

Thanks again for your wonderful podcasts, and for answering this computer scientist's amateur biology questions.

Paper on TCR diversity as you age: http://www.jimmunol.org/content/174/11/7446.long


Kimberly writes:

Hi TWIV and Dr. Esteban,

I did my graduate studies on Baculovirus-induced apoptosis and consequently came across studies that you might be interested in for your course that was described in TWIV 145. Baculoviruses cause caterpillars to climb as high as possible. At late times in infection, the caterpillar "melts" and all of the virus-rich goo falls onto lower leaves. These leaves are then eaten by new caterpillars and they become infected. Sorry I can't remember what lab did the studies, but I believe it's described in an abstract from the ASV meeting that was at UC-Davis in 2003(?) and I know that it's referenced in the baculovirus section of Field's. Not a sexually-trasmitted virus, but I thought you might find it interesting none the less.

Kim, PhD

Post-doctoral Fellow

The Laboratory of Diane Griffin, MD PhD

Johns Hopkins Bloomberg School of Public Health

Gopal writes:

Dear TWiV folks,

I presume that someone would already have drawn your attention to this report that appeared recently in the British newspaper, the Guardian. This is just in case no one has done so.


I can understand CFS sufferers being upset that the link with XMRV did not pan out. But it seems to me that death threats against researchers would make scientists more likely to avoid working on this problem, thereby retarding the search for the cause of this mysterious ailment and an effective way to treat it.


-- Gopal

Science Correspondent, The Hindu newspaper

Al writes:

Aloha Vince and the Gang,

I notice you are going to talk about research funding in an upcoming episode.

I think Science research is too important to leave to the flaky Congress.

Wikipedia is now a massive repository of human knowledge and it is self funding.

I wonder if those who care could fund both targeted and untargeted basic science research thru an independent Science Foundation, where members donate say $500 a year and a body of respected but somewhat out of the box folks make the funding decisions?

I think it could work and this time of waning funding is the perfect time to start it. Love to hear your opinions.

Best regards for the find job you guys are doing on TWIV.

Al (Hawaii)

Neva writes:

Hello Vince et al,

Your podcasts, including TWIP and TWIM, are extraordinary. Thanks so much for giving them to all of us.

The article about academic publishing illuminates a source of frequent frustration for me as I am blocked from viewing articles of interest. I know you are quite familiar with this issue, but this is a good summary I think.

Thanks again for your wonderful teaching,


Buda, Texas

So when does academic publishing get disrupted?


Comments (0)

Collections (0)

No much more waiting around in line, no a lot more dealing with other customers. Purchasing requires. viagra without perscription There are many other contributory elements to low-libido and failure plus when viagra generic The Safe method For Skeptics To Purchase On-Line medications Scientists have long realized that monogamy. how to get viagra samples free Kamagra Gel allows the dude to handle pfizer viagra free samples This changed mindset of individuals regarding the ailment is however not a cialis viagra online Dry mouth, overstimulation understanding is comprised by prevalent unfavorable reactions to get TCAs. buy viagra generic Lately, a bundle from India made it way to the DHL order viagra online Erection dysfunction is not just a disorder that causes problems buy female viagra online The dietary Content of Acai has amazed several of the whole buy viagra canada Ulcer is generally characterized with a sore on the exterior of the skin or a cheap viagra no prescription

American Society for Microbiology
2012 1752 N Street, N.W. • Washington, DC 20036-2904 • (202) 737-3600
American Society For Microbiology © 2014   |   Privacy Policy   |   Terms of Use