Virology pop quiz

2 June 2009

cfn_header1The following is from a story posted 2 June 2009 in Central Florida News 13:

OCOEE — Grief counselors will be available at Ocoee High School Tuesday after a student died suddenly from an unidentified virus Sunday.

Here are my questions.

1. How can it be stated that the student died ‘from an unidentified virus’ if no virus was identified?

2. Assuming that a virus was responsible for the student’s death, how would you identify it?

Post your answers in the comments section.

  • Dunbar

    First thing that pops into my mind for question 1 is serum interferon? Or possibly antibiotics didn't have a visible effect. With regard to the second, I know bacteria get cultured for diagnoses– so maybe one should try culturing whatever it is?

  • Zachary

    The link is saying it may have been bacterial meningitis now.

  • http://www.virology.ws profvrr

    That's the answer to part 1 – there was no way for them to know that
    it was a viral disease unless they could isolate a virus. Question #2
    is still valid for understanding in general how viral diseases are
    diagnosed.

  • ET

    I suppose I would start with a good assessment. If the student is already dead, then find out what their symptoms were before the died-Fever-how high and for how long-rash-nausea-cough etc. This alone could help to rule some things in or out. (virus/bacteria/parasite) What was the order of their symptoms, and how long did they last; and also what was tried by that student to treat them (antipyretic for fever etc)

    Additionally, some rudimentary epidemiology would also be helpful. Where were they the day before they got sick? Were at the zoo playing 'toss the poop' with the monkeys, or perhaps just been returning from an overseas trip, working in a lab somewhere, working in an ER, all this could be beneficial to know before narrowing down your search further. (For example-camping trip could steer you more towards vector borne infections-coming back from volunteering at a refugee camp could maybe indicate waterborne-)

    After all that is said and done, then you can start getting to the PCR, RTPCR, and ELISA for more specific viruses, assuming those test options are available. Does animal control euthanize the animal that bit you anymore, to look for negri bodies in the case of rabies? Seems like when I was working in the ER, if there is any doubt, then begin treatment. Still, that is a test option-NEgri bodies I mean-

    If it is something completely unknown, then I maybe try to grow it in culture, and beyond that, Im not entirely positive, although rest assured, I would be in frequent contact with Dr. Racaniello and the rest of the TWiV team!

    ET

  • thor183

    In regards to part 1 – yet doctors do this all the time. that is, they diagnose viral infection without identifying the virus. It's kind of a degree of certainty thing, isn't it?

  • http://www.virology.ws profvrr

    This is done all the time – everyone assumes they have a viral
    infection without actually identifying a virus. It happens all the
    time in sports – 'so and so has a stomach virus and can't play', and
    the press is particularly guilty of spreading incorrect assumptions.
    This article was no different – which is why I wanted to highlight it
    in this way.

  • Lee

    Is there really no way for them to have known without isolating a virus? The immune response to a bacterial infection would have been primarily neutrophils and given the infection's severity one might have seen bands as well. If there was, say, a high CD8+ T-cell response and such serum markers of bacterial infection were absent, wouldn't a viral infection be a reasonable hypothesis?

  • http://www.virology.ws profvrr

    One can certainly suspect that a virus might be involved, and your
    suggestions for ruling out bacterial infections are good ones. But to
    say the boy died of a viral infection is not possible unless a virus
    has been isolated. In most viral infections, symptoms are not
    sufficient for diagnosis, and neither is ruling out other agents.

  • http://www.virology.ws profvrr

    Symptoms might provide clues about what to look for – respiratory
    infection, paralysis, hemorrhagic fever. If you want to identify the
    virus by PCR, then you will have to have some idea what general family
    the virus belongs to. If you have flu-like symptoms, look for flu. The
    recent identification of Lujo virus is a good example. None of the
    known hemorrhagic fever causing viruses were present in the patients.
    So they did what no clinical lab could – sequenced total RNA from
    patient samples.

  • http://www.facebook.com/people/Corey-Philipp/799897312 Corey Philipp

    First it was a virus and now bacterial, do you believe them? :) Who knows when the media will get the correct information? I would like to know how they confirmed the meningitis cause. I'm sure the autopsy has reveled information about swelling but was the bacteria cultured or did the coroner just say I’ve seen this before and ta da we have bacteria.

    I also noticed that there was a warning released about fresh water amoeba below the article linked above. That’s a nasty little parasite I wonder if they are infected with the Mimivirus which in turn was infected by the Sputnik virophage?

  • http://www.facebook.com/people/Corey-Philipp/799897312 Corey Philipp

    First it was a virus and now bacterial, do you believe them? :) Who knows when the media will get the correct information? I would like to know how they confirmed the meningitis cause. I'm sure the autopsy has reveled information about swelling but was the bacteria cultured or did the coroner just say I’ve seen this before and ta da we have bacteria.

    I also noticed that there was a warning released about fresh water amoeba below the article linked above. That’s a nasty little parasite I wonder if they are infected with the Mimivirus which in turn was infected by the Sputnik virophage?