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TR -- I hear you and believe me I hope you are right. I have two healthy teens. I guess what I didn't effectively communicate is how poisonous it is to a scientific career to display any hint of hyperbole about an issue such as this. To have respected scientists voice concerns like this is...worrisome.
In a display of SA I will now answer your direct question:
SARS was not a walk in the park. If it had a shorter generation cycle it could have been very nasty, given its infectivity rate. The following is all 20/20 hindsight given that flu-SARS comparisons weren't being made at the time of the original SARS outbreak.
I know the virologists are much less concerned about a new SARS outbreak for a variety of reasons. Note that these guys were counseling calm at the time -- as soon as the long generation time and nosocomial nature were determined (mid-cycle of the outbreak). Until then it was anyones guess. I do know these guys are more afraid of flu than Marburg or Ebola -- they've said so.
-- SARS was basically a nosocomial infection, i.e. caught in a hospital environment. Most of those infected were health care professionals. (Exception: Chinese apartment building where contaminated water + interlinked air vents + welded doors (quarantine) = 321 cases from one index case.
-- SARS is a coronavirus that is not shed until symptoms exist. It was very infective (each SARS patient infected three others on average, although that Chinese apartment skewed this a bit in my opinion) but it was slow (the geration-to-generation time was 10 days). So, one infection on day 1, three new infections on day 10, nine infections on day 20, 27 cases by day 30, and so on. The slow nature of the spread allowed quarantine and containment.
-- The influenza virus is shed for four or more days before symptoms appear, so an apparently healthy individual can be be spewing virii for a long time before they are isolated. Flu (historically) has a lower number of infections per index case: two new infections per index case but it has a very fast generation rate of three days. This means that one case multiplies into 1024 new infections in 30 days. Each of those 1024 cases in turn becomes a source for 1024 new infections in a month. Pandemic flu is said to spread "explosively" and the analogy is apt. Think of this in the context of our world population distribution. The military is stressing MOUT because there is more UT (I think there were 12 cities of 1 million pop. in 1918 and now there are over 500). One respected researcher -- Osterholm -- has said that panflu would kill more in the first hour than died in the entire SARS epidemic.
-- SARS was eventually traced to a small population of Chinese horseshoe bats. It made it into the human population probably due to the Chinese prediliction to eat anything organic. H5N1 has a vast resevoir in birds: house sparrows, ducks, chickens, geese, swans, grouse -- virtually everything that flaps wings.
-- H5N1 kills by cytokine storm, i.e. it turns the immune system against the patient. The stronger the immune system, the greater the chance of death. (Hence my worry about my kids).
-- Historical probability. There were three outbreaks of pandemic flu in the last 100 years -- one savage and two weak ones. Epidemiologists have evidence of periodic outbreaks - averaging 3 per century with one major one per century - going back 400 years. These guys expect flu to hit again eventually and see H5N1 as having all the hallmarks of a potential Big One.
-- Stunning lethality of H5N1 -- researchers are talking about innoculating 100 chicks with H5N1 and having 100% lethality in 12 hours. With other flu they see 12-18% in a week.
I must go. I'll finish later.
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