The November/December 2006 issue of the AARP magazine carried an interesting story on pandemic flu. The expert virologist who authored the article painted a grim picture of the future of the coming pandemic and gave one view of how to prepare.
Let's set the record straight.
Almost all of our predictive models for pandemic flu are based on 1917/1918 Spanish flu (which actually originated in Kansas); the 1957/1958 pandemic and the 1968/1969 pandemic. The 1918 Spanish flu is known in virology circles as H1:N1. Genetic reconstruction has allowed us to isolate this virus from pathologic specimens collected in 1917 and 1918 and stored by the U.S. military and other organizations. This means that we can now study the actual virus H1:N1 aka the Spanish flu and compare it to the current pandemic risk H5:N1 aka Avian flu. What makes avian flu more likely to be a pandemic?
As we all know now from the media, influenza virus mutates over time. Small mutations are known as antigenic drift while large mutations are known and antigenic shift. These drifts and shifts slowly change the virus from something that the human immune system can recognize and therefore protect against to something that is novel or new to the human population – a pandemic. In short it is something that the human immune system has never seen before.
In 1918 the H1:N1 strain was seen. Like all of pandemics before, it struck with a predictable infection rate (attack rate); approximately 1 in 3. Of these 1 in 3 on average in the population half would become seriously ill. Half of those would develop severe lung disease and half of those with the severe lung disease would ultimately die.
The picture changes significantly, however when you look at the infection by age group. H1:N1 caused virtually no more deaths in those over age 65 than the average flu. In fact in 1918 you were no more likely to die of the pandemic if you were over age 65 than you had been in 1915 or than you would be in 1920.
So what does that mean for the coming Avian flu (H5:N1)? Pandemics are very consistent. They act virtually the same every time they occur as long as they are a novel avian virus. H5:N1 has not been different to date. It is expected to cause no greater number of deaths in those greater than age 65 than the flu did last year in 2005 or the year before in 2004.
Yes, there will be an increase in the number of people who become ill across the age spectrum from birth to those over 100.
Yes, there will be a total increase in the number of people who die. Unfortunately the vast majority of those will be between the ages and 15 and 40. This was the age group that showed the greatest increase in death rate in 1918, in 1958 and 1969.
AARP magazine is to be tremendously complimented in their January/February edition they published an exquisite interview with Anthony Fause, a noted expert in infectious disease and pandemic preparedness. That interview asked insightful questions and gave good, logical answers. Unfortunately the same cannot be said of the recommendations made in the November/December edition.
The article in the November/December edition recommended stockpiling food and other supplies in anticipation of infrastructure collapse and supply chain failure. This advice ignores the lessons learned from history. In 1918, as with all other pandemics, 100 percent of the population was exposed despite social isolation efforts. In 1918, one third of the working population was out of work and yet food was still delivered. Farms still produced. Society did not collapse. There is no reason for panic.
Stockpiling medication is also a formula for disaster and disappointment. The current strain of H5:N1 is already showing resistance to Tamaflu, requiring far higher than usual and longer than usual doses to be effective. Tamaflu's shelf life is also far shorter than the window of likely infection from the pandemic (as late as 2012). This means that you may purchase Tamaflu and have it expire before the disease attacks.
Finally, previous pandemics have come in multiple waves over an 18 month period. In most cases the disease appears first as a low level infection in the population, followed by a large flood of influenza and then an aftershock of disease. You simply cannot stock enough Tamaflu for all three events. You cannot prevent yourself from being exposed during those three events. And you cannot stock 18 months of food and water to safeguard yourself and your family during that event.
So what can you do?
Bring pressure to bear on the healthcare community to better prepare for surge capacity.
There are fewer than 1,000,000 hospital beds in the United States and in an average cold and flu season fewer than 40,000 hospital beds are empty. The federal government recommends between 150,000 and 190,000 available hospital beds even during the peak of an average cold and flu season. The United States is woefully short of hopsital beds and it falls to private hospital corporations to provide that surge capacity.
The New England Journal of Medicine in 2004 an article by Dr. Michael Osterholm they found there are 105,000 ventilators in the United States. Eighteen percent of those are either broken, in repair or in cleaning at any given moment. Sixty-seven of those are in chronic use for ventilator dependent patients outside of the hospital. This leaves 16,000 ventilators available nationwide.
If we break down the expected number of illnesses just in those over age 65, those 16,000 ventilators will all be in use. What happens to those between age 15 and 40, the children and grandchildren of those who read the AARP magazine?
The healthcare community must step up to the plate rather than pedaling panic in the pages of the AARP magazine. The juxtaposition of the Avian flu article in the November/December issue and the far more insightful and useful interview in the January/February issue show the division within the house of medicine. The AARP magazine has the largest circulation and readership in the English-speaking world. Which side of that division will its members come down upon - Panic or preparedness?
It was once said of the generation that now reads the AARP magazine that they are the "Great Generation".
The Great Generation earned this title because of their self-sacrifice during World War II. They guided a great nation through an industrial revolution and a technological revolution that became an economic revolution that swept the planet. Many have tried to discount the Great Generation because they are now the "Geriatric Generation." I believe the Great Generation will lead us again not into panic but into a new era of preparedness.
i enjoyed your insight, but would disagree with one point.
there were varying attack rates in different cities due to the different strategies they took in isolating populations through such measures as closing schools and movie theaters. the ones that did close schools and other public places had much lower infection rates than those that did not act early to isolate populations.
watch this video for a comparison of two cities and the approach each took in 1918:
http://www.scribemedia.org/2006/12/18/pandemic-preparedness/
Posted by: peter | December 25, 2006 at 10:56 PM