Comment Pandemics come in cycles - one severe, next 2 not (Score 1) 257
In 2005 I attended two conferences on Pandemic Flu issues here in Washington state. The best of dozens of seminars was given by an experienced epidemiologist at which I took notes and voice recorded the session. Subsequent independent reading has made me very concerned about the mutation potential of H5N1 and it's similarity to the 1918 influenza virus.
Concerning the comment about the Hong Kong Flu of 1969 not being very severe, this is true, however the worrisome aspect is that it fits a longer pattern in influenza pandemics of a deadly devastating pandemic followed by roughly two (sometimes 3) less lethal ones in the following 70-100 years, then another extremely virulent pandemic circles the globe claiming millions of lives. A few years ago researchers were able to examine army samples of infected 1918 tissue and found the biology of H5N1 is much closer to that of the Great 1918 Pandemic than the pandemics of 1957 Asian Flu or 1968 Hong Kong Flu.
H5N1 has an extremely high lethality once it lodges in the lower lungs of it's victims (most common yearly wintertime influenza bugs attach to receptors in our upper respiratory tract). The theory is that H5N1 has not acquired the ability to fit easily onto anything other than deep lower respiratory cells, which is one reason it has not spread easily into human hosts even those that spend lots of time in close proximity to infected birds. Since all influenza viruses mutate rapidly (it's in their RNA to do so) the fear in the medical community is that eventually H5N1 (or one of the other variants which I understand is now infecting pigs) will by random chance hit upon a mutation in one of it's rare human hosts that combines the easy human to human transmissivity of a similar virus (upper lung attachment sites for example) with H5N1's own unique lethality. The result will be a super killer virus that after it has run havoc thru the available host population in multiple waves (in 1918 these were several months apart) it only dies out when most of the surviving hosts have seen the virus before and developed antibodies that are able to attack the virus before it can overwhelm the bodies defenses.
Now for the really depressing news. During the "Great 1918 Influenza" the most likely to die after infection were NOT the old, infirmed or the very young. You stood a much greater chance of dying a horrible agonizing death, coughing up blood from your dissolving lungs if you were "able-bodied" and in the prime of health. The largest numbers of deaths occurred among those 20-40 years old. Among the medical teams in 1918 desperately working to save lives this was a baffling mystery. The best evidence I am aware of indicates the original infection occurred in a small Kansas farming community near a huge newly built (and squalid) army base which was housing thousands of new soldiers destined for the European trenches in WWI. Most of the soldiers were young, physically fit , but living in miserable conditions, stuffed into hastily constructed barracks or tents in the middle of winter. When shipped out on the rail system they spread the virus to major transit centers and eventually to Europe. The early virus had not yet matured to it's most lethal version, but it now had a vast host population to mutate within until it achieved a deadly state of influenza perfection. It was called the "Spanish Flu" because Spain was the only government willing to allow the press to report the outbreak of a deadly mysterious new illness. All the other major governments were suppressing any news which might hurt the war effort or give comfort to the enemy.
The other US population segment that had very high mortality rates were pregnant women. Depending on the wave, between 23% - 71% died if infected. Think about that number for a while.... Imagine the consequences to our grandparent's society if the worldwide fatality rate for all population segments had been say 50% instead of 3%-4% which historians estimate as the toll from the 1918 pandemic. I am not a medical person (my younger brother has that distinction in our family) so my understanding of the pathology of the 1918 and possible H5N1 viruses is based upon the reading I have done, conferences attended, etc. and might not be accurate in all details, but here goes. Much has been made of the advances in modern medicine since the 1918 influenza scourge. Many talking heads interviewed on TV news a couple years ago spoke reassuringly of vastly improved pneumonia treatment protocols of today. Respirators and Tamiflu would save lives that doctors in 1918 had not been able to. Unfortunately, this is not all that accurate, for reasons that I do not have time to elaborate upon (and understand too poorly). The short answer is; regular pneumonia did not kill the greatest number of victims of 1918. Doctors then were a pretty talented and capable bunch. They tried treating patients with many of the same techniques we would use today for pneumonia and still they died horrible agonizing deaths by the hundreds-of-thousands. These same physicians developed techniques which are thought of as the basis of what we call modern medicine so they were not backwoods witch-doctors. Indeed many from that era are still considered among the giants of medical science.
What healthy young adults then were falling victim too (and what we many face ourselves next month or several years from now) was most likely a Cytokine Storm response by the body. This is sometimes seen in emergency rooms today, rare but not unknown. It happens when the bodies internal defenses are triggered into a massive production of Cytokine which while very helpful in fighting infection in small doses, can be quite lethal when introduced into the body (usually the lungs) in large amounts. When concentrated, Cytokine dissolves tissue. That is why the 1918 victims coughed up so much blood, their own bodies immune response was producing a chemical that destroyed lung tissue, leading to suffocating fluid in the lungs. You died gasping for air a victim of an immune system desperate to combat a microbial foe it had no natural defenses for. My understanding is; something about the chemistry of the H5N1 type virus attack triggers the wrong response, a life threatening, counter-productive massive Cytokine response from the human host.
Modern medicine today has no effective treatment for a "Cytokine Storm" and the massive inflammation it triggers. If I was rushed to the local hospital emergency room here in Seattle suffering from this rare condition I would like the 1918 victims our great-grandparents knew, likely be dead by the next morning . There are historical accounts from the Great 1918 Influenza of healthy office workers feeling ill, walking home, only to die in agony by noon the next day. This happened in our past and it will happen again. The variables are; what morbidity rate, how easily communicable and how many months do we have to wait in social isolation for a vaccine to be available. Keep in mind that existing vaccine technology requires many months AFTER an influenza virus appears in mutated form before it can be produced. This is not the same as generic flu shot cocktail mixes we recommend for the old and very young. A pandemic virus vaccine has to be tailored for the specific mutation which emerges from the wild.
Sorry the above is so depressing. I have a lot more info and some ideas regarding what can be done to avoid large numbers of fatalities but it is 4:46am here in Seattle and I must leave that for another post, hopefully tomorrow..er..later today.
-- Mark-in-Seattle
Concerning the comment about the Hong Kong Flu of 1969 not being very severe, this is true, however the worrisome aspect is that it fits a longer pattern in influenza pandemics of a deadly devastating pandemic followed by roughly two (sometimes 3) less lethal ones in the following 70-100 years, then another extremely virulent pandemic circles the globe claiming millions of lives. A few years ago researchers were able to examine army samples of infected 1918 tissue and found the biology of H5N1 is much closer to that of the Great 1918 Pandemic than the pandemics of 1957 Asian Flu or 1968 Hong Kong Flu.
H5N1 has an extremely high lethality once it lodges in the lower lungs of it's victims (most common yearly wintertime influenza bugs attach to receptors in our upper respiratory tract). The theory is that H5N1 has not acquired the ability to fit easily onto anything other than deep lower respiratory cells, which is one reason it has not spread easily into human hosts even those that spend lots of time in close proximity to infected birds. Since all influenza viruses mutate rapidly (it's in their RNA to do so) the fear in the medical community is that eventually H5N1 (or one of the other variants which I understand is now infecting pigs) will by random chance hit upon a mutation in one of it's rare human hosts that combines the easy human to human transmissivity of a similar virus (upper lung attachment sites for example) with H5N1's own unique lethality. The result will be a super killer virus that after it has run havoc thru the available host population in multiple waves (in 1918 these were several months apart) it only dies out when most of the surviving hosts have seen the virus before and developed antibodies that are able to attack the virus before it can overwhelm the bodies defenses.
Now for the really depressing news. During the "Great 1918 Influenza" the most likely to die after infection were NOT the old, infirmed or the very young. You stood a much greater chance of dying a horrible agonizing death, coughing up blood from your dissolving lungs if you were "able-bodied" and in the prime of health. The largest numbers of deaths occurred among those 20-40 years old. Among the medical teams in 1918 desperately working to save lives this was a baffling mystery. The best evidence I am aware of indicates the original infection occurred in a small Kansas farming community near a huge newly built (and squalid) army base which was housing thousands of new soldiers destined for the European trenches in WWI. Most of the soldiers were young, physically fit , but living in miserable conditions, stuffed into hastily constructed barracks or tents in the middle of winter. When shipped out on the rail system they spread the virus to major transit centers and eventually to Europe. The early virus had not yet matured to it's most lethal version, but it now had a vast host population to mutate within until it achieved a deadly state of influenza perfection. It was called the "Spanish Flu" because Spain was the only government willing to allow the press to report the outbreak of a deadly mysterious new illness. All the other major governments were suppressing any news which might hurt the war effort or give comfort to the enemy.
The other US population segment that had very high mortality rates were pregnant women. Depending on the wave, between 23% - 71% died if infected. Think about that number for a while.... Imagine the consequences to our grandparent's society if the worldwide fatality rate for all population segments had been say 50% instead of 3%-4% which historians estimate as the toll from the 1918 pandemic. I am not a medical person (my younger brother has that distinction in our family) so my understanding of the pathology of the 1918 and possible H5N1 viruses is based upon the reading I have done, conferences attended, etc. and might not be accurate in all details, but here goes. Much has been made of the advances in modern medicine since the 1918 influenza scourge. Many talking heads interviewed on TV news a couple years ago spoke reassuringly of vastly improved pneumonia treatment protocols of today. Respirators and Tamiflu would save lives that doctors in 1918 had not been able to. Unfortunately, this is not all that accurate, for reasons that I do not have time to elaborate upon (and understand too poorly). The short answer is; regular pneumonia did not kill the greatest number of victims of 1918. Doctors then were a pretty talented and capable bunch. They tried treating patients with many of the same techniques we would use today for pneumonia and still they died horrible agonizing deaths by the hundreds-of-thousands. These same physicians developed techniques which are thought of as the basis of what we call modern medicine so they were not backwoods witch-doctors. Indeed many from that era are still considered among the giants of medical science.
What healthy young adults then were falling victim too (and what we many face ourselves next month or several years from now) was most likely a Cytokine Storm response by the body. This is sometimes seen in emergency rooms today, rare but not unknown. It happens when the bodies internal defenses are triggered into a massive production of Cytokine which while very helpful in fighting infection in small doses, can be quite lethal when introduced into the body (usually the lungs) in large amounts. When concentrated, Cytokine dissolves tissue. That is why the 1918 victims coughed up so much blood, their own bodies immune response was producing a chemical that destroyed lung tissue, leading to suffocating fluid in the lungs. You died gasping for air a victim of an immune system desperate to combat a microbial foe it had no natural defenses for. My understanding is; something about the chemistry of the H5N1 type virus attack triggers the wrong response, a life threatening, counter-productive massive Cytokine response from the human host.
Modern medicine today has no effective treatment for a "Cytokine Storm" and the massive inflammation it triggers. If I was rushed to the local hospital emergency room here in Seattle suffering from this rare condition I would like the 1918 victims our great-grandparents knew, likely be dead by the next morning . There are historical accounts from the Great 1918 Influenza of healthy office workers feeling ill, walking home, only to die in agony by noon the next day. This happened in our past and it will happen again. The variables are; what morbidity rate, how easily communicable and how many months do we have to wait in social isolation for a vaccine to be available. Keep in mind that existing vaccine technology requires many months AFTER an influenza virus appears in mutated form before it can be produced. This is not the same as generic flu shot cocktail mixes we recommend for the old and very young. A pandemic virus vaccine has to be tailored for the specific mutation which emerges from the wild.
Sorry the above is so depressing. I have a lot more info and some ideas regarding what can be done to avoid large numbers of fatalities but it is 4:46am here in Seattle and I must leave that for another post, hopefully tomorrow..er..later today.
-- Mark-in-Seattle
