The purpose of this blog is to teach you about viruses and viral disease. This topic is not one that everyone understands, yet nearly everyone would like to. I was most disturbed when the Secretary of Health and Human Services, Tommy G. Thompson, referred to the anthrax bacillus as a virus. That incident crystallized in my mind the need to better educate the public about viruses.

I am your host at virology blog – Vincent Racaniello Ph.D., Professor of Microbiology & Immunology in the College of Physicians and Surgeons of Columbia University. Why am I qualified to teach you virology? I have done laboratory research on viruses since 1975, when I entered the Ph.D. program in Biomedical Sciences at Mt. Sinai School of Medicine of the City University of New York. My thesis research, in the laboratory of Dr. Peter Palese, was focussed on influenza viruses. That’s me in the black and white photo below, taken in 1977. Yes, I’ve changed.

Vincent Racaniello 1977

In 1979 I joined the laboratory of Dr. David Baltimore at Massachusetts Institute of Technology, where I did postdoctoral work on poliovirus. The moratorium on cloning full-length viral genomes had just been lifted, so I proceeded to make a DNA copy of poliovirus RNA, using the enzyme reverse transcriptase. I cloned this DNA into a bacterial plasmid and determined the nucleotide sequence of the poliovirus genome. In an exciting advance, I found that a DNA copy of poliovirus RNA is infectious when introduced into cells. This was the first demonstration of infectivity of a DNA copy of an animal RNA virus, and it permitted previously unthought of genetic manipulation of the viral genome. Today infectious DNA clones are used to study most viruses.

In 1982 I joined the faculty in the Department of Microbiology at Columbia University College of Physicians & Surgeons in New York City. There I established a laboratory to study viruses, and to train other scientists to become virologists. Over the years we have studied a variety of viruses including poliovirus, echovirus, enterovirus 70, rhinovirus, and hepatitis C virus. As principal investigator of my laboratory, I oversee the research that is carried out by Ph.D. students and postdoctoral fellows. I also teach virology to undergraduate students, as well as graduate, medical, dental, and nursing students.

Since I think about viruses every day, and I have always been interested in teaching others about viruses, this blog seemed to be an ideal forum to convey some of my knowledge on this topic.

After starting this blog, I became interested in using ‘new media’ (internet-based media) to disseminate information about viruses. I’ve summarized my use of this format in an article entitled “Social media and microbiology education“, which you can find at the open-access journal PLoS Pathogens. In addition to writing about viruses on virology blog, I also host and produce three podcasts: This Week in Virology, This Week in Parasitism, and This Week in Microbiology. I teach a virology course each spring at Columbia University, and I post videocasts of each lecture at the course website, at iTunes University, and at Coursera.

If you would like to learn about our work on viruses in more detail, please visit my website at Columbia University, or my Wikipedia page. You might also like to follow me on Twitter or Google+, where I often provide links to interesting stories about viruses. I have also written about my work on this site; links to some of these articles are provided below.

Earth’s virology course

Thirty years in my laboratory at Columbia University

Edwin D. Kilbourne, MD, 1920-2011 (his influence on my career)

Thirty years of infectious enthusiasm

Transgenic mice susceptible to poliovirus

Viruses and journalism: Poliovirus, HIV, and sperm

Poliovirus on BBC radio

Viruses and journalism: Off-the-shelf chemicals

Poliovirus is IRESistable


All of the opinions that I write on this blog are mine, and in no way represent the views of my employer, Columbia University. This information is provided for educational purposes only, and should not be considered medical advice. If you think you are sick, see your doctor. Links to other sites to not constitute endorsements of those sites.

Vincent Racaniello

  • http://www.virology.ws profvrr

    Correct, both DNA strands can code for proteins in viral and eukaryotic genomes.

  • http://www.virology.ws profvrr

    Influenza pandemics occurred 100 years ago as they do today despite
    the population increase. The rate of spread may be higher but
    virulence has not increased. There is no a priori reason for viral
    virulence to increase as it passes through a population. On the
    contrary, viruses evolve to become more transmissible, not more
    virulent. Because viruses require a host there is no evolutionary
    advantage to destroying that host.

  • pteropid

    Hi Guys,

    I thought Dick would like this one, although he may have already seen it.


    Very clever stuff.

  • Byron Calgua

    I follow your vey interesting blog since a long time. I´m PhD student and I work with viruses and prions in the environment.

    I would like your opinion or see information in your blog bout the “inactivation models for microorganisms”. For example Chick-Watson model (the meaning of the values in the ecuation of the line).

    Best wishes!!!

  • Byron Calgua

    I follow your vey interesting blog since a long time. I´m PhD student and I work with viruses and prions in the environment.

    I would like your opinion or see information in your blog bout the “inactivation models for microorganisms”. For example Chick-Watson model (the meaning of the values in the ecuation of the line).

    Best wishes!!!

  • RR

    Judy Mikovits defends the original XMRV study against the European failures to replicate …


    Science 14 May 2010:
    Vol. 328. no. 5980, p. 825
    DOI: 10.1126/science.1184548

  • RG

    Errr …. what makes you so positive that viruses play no role in psoriasis? I've been listening to TWIV since episode I, but have not looked at your blog before today. I don't know anything about psoriasis, but I do follow the research on two other autoimmune diseases (which I have) – Type I diabetes and Rheumatoid arthritis. Researchers have identified genes in the HLA complex on chromosome 16 that confer a risk for T1D, and genes that are protective. But twin studies show that environmental factors plays a large role in Type 1 diabetes. In monozygotic twins, if one twin develops type T1D, the chances of their twin developing the disease is about 50%.


    The consensus is that genetics confer a risk for T1DM, but one or more environmental exposures or insults are necessary to trigger the disease. The list of potential environmental triggers is long. Both maternal infection and childhood infection are high on the list of putative environmental factors in T1DM. Epidemiological studies in the 1960’s identified a correlation between consackie outbreaks and the incidence of T1D. More recent research using mouse models has identified a possible mechanisms by which infection with consackie virus could trigger an autoimmune reaction.


    The NIH is conducting a large cohort study (TEDDY) to investigate environmental factors contributing to, or protecting against, T1DM.


    In RA, environmental factors play an even larger role than in T1DM. In monozygotic twins the risk of the second twin developing RA in only 15%. Again, infectious agents are on the list of putative environmental factors.

  • Gail Christie

    There are also several examples of genetic elements that are not defective viruses, but that are able to “pirate” certain bacterial viruses to encapsidate their own genomes. One such example is satellite phage P4; another is provided by a family of staphylococcal pathogenicity islands called SaPIs. In both cases these elements can modify the assembly pathway of their helper viruses to make smaller capsids that exclude the viral genome but accommodate the smaller genome of the other replicon. There are also other interactions, at the levels of gene regulation and DNA packaging, that assist in the exploitation of the helper virus.

  • http://www.theravive.com/ The Counselor

    great point! I completely understand what you are saying.

  • http://internal-optimist.blogspot.com/ Internal Optimist

    Thank you very much for your helpful and informative page. Just what a MedStudent needed! :)

  • Mel

    Love, love, love your podcast. On the topic of CFS and XMRV, I though you might find a segment from a 1996 episode of 'Primetime' interesting. It's at rescindinc.org/primetime1996.wmv . It gives some background on the intensity you're seeing among the CFS patient population in regard to the CDC and the paper the CDC released last week. In addition, I think you might find some of Dr. Suzanne Vernon's comments on the study interesting. She is the Scientific Director for the CFIDS Association of America and spent 10 yrs. at the CDC studying CFS. Her article can be found at cfids.org

  • voner

    Vince: I think you & your podcast are great. Helping us out there in the world understand viruses. I have 2 questions.

    The first question is: do you have any your podcasts that are about enteroviruses??

    here's a recent reference from the Federal Register — using a reference that one of your cohorts recommended as a ” pick of the week”..


    can you enlighten us some time as to what this note in the federal register about the National Cancer Institute and SAIC probably indicates?



    I'm a student in CPU (China Pharmaceutical University) in Nanjing, I wanted to know whether it was possible to change to Wuhan university, because I'm really interested in Virology and I think Wuhan would be better for my studying. And is there any program taught in English there?

    Thank's for responding me. Sincerly Yours.

  • Guest

    This is debated topic, actually, and still an open scientific question.

    There are many potential causes for psoriasis, autoimmune disorders only being one of many.

  • Guest

    Are you saying that H1N1 and HIV are related in some way?

    It sounds like you are mixing apples and oranges….what do you really want to say?

  • Guest

    RNA viruses like influenza can modify each other through antigenic shift during replication.

  • Edwin

    This may be too simple a question. How are flu viruses inactivated (they say “killed”, but I know they are technically not alive) for use in vaccines?

  • akhil_patel

    I know this but I wanted them independently…

    thanx for replying..

  • http://www.virology.ws profvrr

    The inactivated influenza virus vaccine is rendered non-infectious by

    treatment with detergent and formalin. The former disrupts the

    particle, while the latter cross-links the virion proteins.

  • Sly

    I would like to study Virology, but this speciality doesn’t exist as a major. So which choice would be the best: studying ‘Microbiology, Immunology, Molecular biology, Pharmacology, Biochemistry…” Thank’s for the answer. 😀

  • http://www.virology.ws profvrr

    Technically virology is a sub-field of microbiology, so majoring in
    that subject would be suitable. Molecular biology would also be good.

  • Bibislimhot

    Thank you for you help, so I have to choose between “Wuhan university” in China or “Paris 5” in France. I think both of them teach that field.

  • GB

    exceptions being viruses that DO have an evolutionary advantage to destroying their host, such as rabies (when a dead host does increase transmissability)

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  • Yashar

    i dont think if you can calculate moi from rna or dna copy number. yashar

  • Cristina Ibba

    Dear Vincent I’m a Post Doc student. I found some protocols regarding the preparation of stock for viruses that need a criolisi, in which they say to do three criolisis, some others say just one. What do you think about that? Is it better one or three? Which would it be the difference, if there is any?
    Thank you very much for your help
    Regards, Cristina

  • http://www.virology.ws profvrr

    I guess by ‘criolisi’ you mean freeze and thaw? The number you do
    really depends upon the virus. Some viruses, like poliovirus, are
    quite thermostable and can survive three cycles. Rhinoviruses, on the
    other hand, are not thermostable and for those we only do one. The
    real question is whether three versus one improves the yield
    significantly (for thermostable viruses) – I haven’t compared one
    versus two versus three.

  • tommy

    Dear Vincent,
    I am a Doctor course student in chemistry dealing with supermolecular chemistry. I have a small question on the viral capsids self-assembly process: If two different protein subunits from two kinds of virus arm mixed for the self-assembly, what would happen? Will  they self-organize into two distinct capsids or they just intervene each other forming another new mixed capside? Do you have any references concerning this scenario?
    Thank you in advance for your kind attention.

    Anyone seeing this have some answer please do not hesitate to respond.


  • http://www.virology.ws profvrr

    The answer depends on how different the capsid proteins are: whether
    they are from highly related or distant viruses. For closely related
    capsid proteins, there may be ‘mixing’ of capsid components to form
    virus particles, but distantly related will not mix to form particles.

  • Peter

    Dear Vincent,

    I have a classic virology question for you:
    It is well known that viruses “push” cells toward the S phase to replicate their genetic material, but my question is do viruses also “push” cells towards G2 and M phases? – I am asking this because I got several results indicating dephosphorylation of Chk1 protein (Ser 347) and ATM protein (Ser 1981) during adenoviral infection. I know that Chk1 controls G2/M checkpoint via CDC25A as well as S/G2 checkpoint. Does the virus use the G2 phase for synthesizing it’s late proteins because during this phase there is extended cellular protein synthesis? And does it use the M phase to release itself from the nucleus after the degradation of the nuclear membrane (in prophase phase)?



  • matthias k

    thanks for this wonderful blog! I stumbled across it when collection information for my MD thesis (dealing with influenza) and as I know very well myself how much work maintaining a website and writing texts are, I deeply appreciate this blog! Thank you!!
    Greetings from vienna, mk

  • Mhawkins

    Have you had a chance to see ‘contagion’?

  • http://www.virology.ws profvrr

    Have not yet seen ‘Contagion’, but certainly plan to do so soon. We’ll devote an episode of TWiV to the movie once all the team has seen it. We’re also accumulating a good number of comments from readers which we will share on that episode.

  • Keshava Murthy


    I came across this page while searching for cause of untimely death occured in my family.

    The symptoms of disease : Fever for 2 to 3 days, fatigue, blood test results showing signs of  Urine Infection, fever continued for next 2 days with loss of stamina and severe fatigue. 4 or 5th day patient would develop spams similiar to epilepsy.  Treated in Intensive Care for 2 days  with Artificial respirator, developed lever failure, kidney failure and ultimately heart attack resulting in death.

    I could count about 10 in my circle of aquitances, who have The same sequense with a subtle variation causing death within 6 to 10 days of infection with symptons of common fever.

    The professional doctors could not diagnoise the disease and focus the treatment.

    Do you have any clues what this could be due to ?  The age group of victims : 30 to 55.

    email : skmurthy_blr@yahoo.co.in

  • Chris

    My gastro doctor today saw me for four weeks of light, on and off nausea, fatigue, etc.  He said that I probably have a chronic virus that doesn’t want to go away.  He said viruses that makes us sick can last for months.   I always thought viruses, like stomach viruses, were supposed to go away after a few days?

  • Jason Adams


    I wanted to show you a cool website. You might want to feature it on your blog as your readers might find it interesting and useful.

    URL – http://www.drugsarchive.com

    Drugs Archive is a source for valuable information on brand and generic drugs. It provides easy-to-read, in-depth, authoritative medical information for consumers via its user-friendly, interactive website.

    Drugs Archive provides the most detailed and credible information about prescription drugs so as to help you feel better about the health of you and your family.

    You can read more about Drugs Archive at http://www.drugsarchive.com/about-us

    Have a look at it, I believe you would like it.

  • Student

    i have a few questions. how does non-envelop viruses(adenoviruses) are capable of surviving freeze-thaw? and another question is why at room temperature  the envoleped viruses make a great decrease in titre compare to non-env viruses?

  • Mbjesp

    Dr. Racaniello, can you please address the potential role off Epstein Barr virus / herpes 6 in CFS / ME?

  • sebastian

    Thank you Vincent. I love your blog!!

  • Ph Perrot Minnot

    Dear Professor Vincent Racaniello,


    all, I ask you, if you please,

    to excuse
    my unformal bad english

    I m french,
    I m sorry for that…

    Your advice about science publication is over true,

    Silences on “fear informations” are worse

    Than trouble they can induce for public impression…


    But when official sciences keep silence

    On IGNORANCES inside their own bases…

    What have we to think about ?

    For exemple all medical doctors

    Don’t known the Calcium color …?

    They all answer “white”… (wrong)

    They ignore that Sulfur/ Calcium / Manganes

    Are the “cycle ke” in emotional deseases…

    They ignore that Na Cl (salt) is the main factor

    In chlorhydric acid production in stomac…

    (the theory teached in all world medecin faculty

    Is false qualitatively and quantitavely,

    The true answer go throuht Sulfur knowledge)


    We are in a world where

    All scientifics ignore a lot of natural things

    And INNOVATION is impossible due to

    The System POWERS…

    I search solutions for health

    With naturals chemical elements…

    I m ready to share 20 years of natural chemical research…

    To offer human bean

    INNOVATION for their health…

    Are you open to real news INNOVATIONS

    Developing the diverse points up-refered ?

    Visite “AB litho veritas” blog (in French)

    You may be discover an other world for to morrow,

    And for everybody in the world…


    Expecting your answer…


    Philippe Perrot Minnot

  • Carolina

    Vincent, I just “discovered” your wonderful site! I wish I would have seen it before. It will become a “must see” for every new member of my lab! Thanks for doing such a great job.

  • Guest

    Hi Vincent,

    I am a high school student, and am completely new to virology, and how viruses work in general. 

    One thing I am curious to know is why exactly some viruses (such as the Hepatitis viruses) aren’t eliminated by antibodies. In other words, why are some viruses easily removed from the body, while others aren’t? 

    I would be very grateful for your help with this.


  • Hope

    Great resource! Thank you for posting this!

  • Peter

    Dear Vincent,
    I have a question. Does the cellular detachment from the petri dish, 1.5h-2h after adenovirus type 5 infection (early stages of infection) can be explained by the viral attachment to the Coxsackie virus and adenovirus receptor (CAR), thus interfering cellular adhesion to the plate?


  • http://www.virology.ws profvrr

    The fiber-knob:CAR interface overlaps with the CAR:CAR interface involved
    adhesion proteins. Therefore fiber could in principle disrupt cell attachment. When adenoviruses leave polarized cells, excess fiber does disrupt CAR dimers, opening up the cell junctions for virus release. On infection, if you use a very high multiplicity of infection, soluble fiber present in the virus stock will also disrupt CAR dimers and cause cell detachment.

  • http://www.virology.ws profvrr

    There are many reasons for this behavior. In some cases (HIV) the virus changes constantly to escape elimination  by antibodies. For other viruses the replication cycle is silenced so that no virions are produced, yet the viral genome remains and can be activated later (latent infection). In some cases the antibodies produced are not correct for elimination.

  • Nick

    Thank you for this blog and thank you for sharing freely years of experience and research. The blog is organized excellently and the material is presented clearly. 

  • Arun

    Dear Sir,

    I heard that inflenza virus mimic the immune system by changing the surface antigen.So in such case the influenza vaccine available in market is effective against common cold.

  • Aebarron

    Dr. Racaniello:

    I am a tenured associate professor of bioengineering at Stanford, and I have just watched the documentary “The Emperor’s New Virus” in its two parts on YouTube.  I am more a molecular biophysicist than a cell biologist, and certainly not a virologist, but I was convinced by this documentary that the case for the non-existence of HIV virions is a pretty strong one; which is to say, the experimental evidence supporting the existence of a unique virus HIV is very weak. Would you do me the favor of watching the documentary, and commenting on it?

    Curious and Open-Minded

  • Aebarron

     Not all viruses can be eliminated by the body quickly, but you need to provide optimal support to your immune system to allow your body to work as fast as possible to control the virus. The best way to do this is to take a lot of Vitamin D3 and Vitamin A (you can buy Cod Liver Oil capsules to get both), and sleep a lot. You will get better, if you also eat a healthy and balanced (fruit and vegetable-centered) diet for a few weeks.