JOHN M. BARRY REFLECTIONS ON CURRENT PANDEMIC
His message is a bit unsettling from the frontlines of H1N1 research: this novel influenza virus is very hard to pin down. In spite of international scientific scrutiny, H1N1 continues to baffle and elude, worrying health officials defending against the pandemic, and challenging some ideas about influenza in general. Says Barry, “A lot of things we thought we knew, the virus demonstrates we knew wrong.”
Barry examines the current pandemic in both historic and scientific context. Most influenza viruses share certain features: They can jump to other species by way of mutation, or by mixing genetic components with another virus that happens to be infecting the same cell at the same time. Influenza pandemics go “as far back in history as we can look,” with 10 occurring in just the last 300 years. Four of the most recent pandemics appear to have rolled out in waves of varying lethality, infecting at peak times some 30% of the human population.
When ordinary influenza viruses are transmissible between humans, novel molecular markers are present. The current H1N1 doesn’t bear these markers, yet is transmissible. There are conflicting reports on whether this flu is more infectious than the seasonal flu. There’s evidence that some people over 60 are resistant, perhaps because they carry antibodies to previous influenzas. And although H1N1 doesn’t exhibit conventional molecular tags for virulence, it is virulent. Unlike seasonal flu, when H1N1 kills, it targets younger people, and it does so through viral pneumonia, as opposed to complicating bacterial infections. “Depending on how you ask the question, it’s either extraordinarily mild, more mild than seasonal flu, or more than 100 times as virulent as seasonal influenza.”
While H1N1 seems stable for the moment, and to some, unthreatening, its path can’t yet be plotted. Some of the most infamous flu epidemics take two years to travel around the world, moving from sporadic activity to “blanketing the entire globe and causing enormous morbidity numbers.” If this flu takes off, history tells us, short of a “retreat on a Vermont mountain with shotguns,” there will be nowhere to hide, says Barry. “This virus is going to find me.”
http://mitworld.mit.edu/video/715
CDC REVISED H1N1 AND YOU BROCHURE
Updated: H1N1 Flu and You Brochure (PDF – 184 KB)
WHO NEW PUBLICATION ON MASS GATHERINGS
WHO has just released a new publication just in time for the Hajj. A helpful tool on managing large numbers of people from the perspective of public health. Information in the report can be useful for smaller event planning as well.