You're right, it's not 1918. Is that good or bad?
December 26, 2006
I know this is long. But it's needed.
I've provided a Summary.
But I encourage you to read the entire post.
I'm trying to help you Think It Through.
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Summary |
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Can future flu pandemics be as severe as the 1918-19 Spanish Flu pandemic?
Some people say "No, we will never see another 1918" because:
While those statements are true on their face and seem reassuring, they overlook three critical factors:
To illustrate, consider:
This post and others that follow discuss the false security offered by many "pandemic naysayers." |
From time to time, people talk about how any future pandemic can't be as bad as the 1918-19 "Spanish Flu" pandemic. As one doctor flatly stated, "we will never see another 1918."
Is that true? Is it absolutely true or just probably true? What leads to this conclusion?
The issue is not whether a pandemic will occur. Health experts are confident pandemics will continue to happen. The question is how severe future pandemics will be.
This is a heart-of-the-matter question because it's key in determining what level of pandemic planning and preparation is advisable. And the way this opinion is expressed also can influence how seriously others take the risk.
In today's post, I'll give you some examples of these "1918 can't happen" observations, then comment on the reasoning of each. Later, I'll extend this discussion to some broader potential consequences of a severe pandemic.
A difference in attitudes?
In case you haven't read my blog long enough to know, I'll tell you up front that I'm very concerned about the prospects for the next flu pandemic. I don't think I'm irrational about it. But I am very concerned - and with good cause, I think. Furthermore, my concerns include the real possibility of a 1918-magnitude (severe) pandemic.
Those of us who are concerned are not saying a severe pandemic WILL happen. We're saying it CAN happen.
The naysayers are saying it WILL NOT happen because it CANNOT happen.
(If you could read their minds, do you think the naysayers believe there is absolutely no possibility of a severe pandemic? I think not. But what they say, often quite pointedly, is that it's not possible. That influences what others think.)
Looking around at others who share this concern, I don't get the sense that they relish the idea of a pandemic ... or of being the one trying to tell others about the threat.
On the other hand, I often feel that those who are loudly "debunking" the warnings about future pandemics take great delight in doing so. To them, every day without a pandemic is simply another day the "flu fearmongers" were wrong. (It's not unlike some who, at the recent end of the relatively quiet Atlantic hurricane season, were saying, "Hey, Mr. Weatherman, where's that 'more active hurricane season' you predicted?")
Reaching the wrong conclusions
I think people have concluded wrongly if they think a 1918-severity pandemic can't happen. Perhaps they reached their conclusion too quickly, without fully thinking it through. They looked at the most obvious, top-layer considerations, quickly satisfied themselves that "there's nothing threatening about this," and never looked deeper. (It's shoot-from-the-hip analysis.) And, in their minds, if anyone else thinks there IS a serious threat, such people are quickly labeled "bird flu fearmongers."
As to other possible causes, sometimes the naysayers' thinking may be constrained by preconceived opinions. They interpret the information so it harmonizes with those opinions. This is a common phenomenon.
It's also possible that some people actually are very concerned about the pandemic threat but say they aren't. (Yes, they'll even say it's not possible to have another 1918-scale pandemic.) There may be different reasons for this, including: (1) Their denial is a coping mechanism against something that truly scares them. (2) They're afraid of scaring others; "we don't want to cause panic." (Risk communications experts like Peter Sandman and Jody Lanard understand these human dynamics far better than I.)
Banking on probabilities and modern medicine
Usually, the pandemic naysayers mistakenly dismiss the pandemic risk by two lines of reasoning:
(1) If asked, "Will a pandemic happen?" they say, "After several years, the much-talked-about pandemic still hasn't happened and very likely won't." In other words, the probabilities are very much in our favor.
We must remember that pandemics are "low probability, high impact" events. They are uncommon and, at any particular time, unlikely. But pandemics do happen from time to time - and when they happen, they're awful.
Unfortunately, the pandemic naysayers overly rely on the "low probability" half of the risk assessment. They need to remember that "low probability" does not mean "never happens." Take 1918, for instance.
We can't let ourselves be seduced by the comfort of "low probability." If we do, we leave ourselves vulnerable. Because "high impact" means "brace yourselves."
(2) If asked, "Assuming we have a flu pandemic, how severe will it be?" they say, "If a pandemic does happen, it won't can't be nearly as serious as the 1918 pandemic because of the medical resources available today." In other words, modern medicine is very much in our favor.
This rationale - other pandemics will happen but "can't be of 1918 severity" - is what we need to talk about in more depth.
The world in 1918
As we'll see, the naysayers reach some of their conclusions based on how the world was different in 1918. So it might be useful to remind ourselves of what the world was like in 1918 (a few examples, at least).
Back then, movies had no soundtracks (that came in 1926), penicillin had not been discovered (1928), there was no DPT vaccine for diphtheria, pertussis, and tetanus (1923-27), the first influenza vaccine had not been developed (1945), the Great Depression had not occurred (1929), and Charles Lindbergh and Amelia Earhart had not made their non-stop solo flights across the Atlantic Ocean (1927, 1935). There was no television (1923-25), no computers (1930), no FM radio (1933), no stereo records (1933), no ballpoint pen (1938), no helicopter (1939), no calculators (1930s), no Leica cameras (1925), the "planet" Pluto had not been discovered (1930), and U.S. women did not have the right to vote (Nineteenth Amendment, 1920).
By comparison, we certainly benefit from much greater scientific and medical knowledge (including veterinary knowledge), many new vaccines and medicines, laboratory resources, faster communications, computing resources, and products such as respirators, latex gloves, and various sanitizers.
With that in mind, let's continue ...
"A different period of medical history"
The second line of reasoning the naysayers offer, noted above, is that we're protected from a severe pandemic by today's medical safety net and healthy living conditions. Specifically, the pandemic doubters say there won't be another 1918-level pandemic because:
- The 1918 flu pandemic occurred "in a different period of medical history" (as another doctor wrote). Today's medical and scientific knowledge and tools supposedly will enable us to fare much better compared to the medical science of 1918. For example:
- Unlike 1918, today we have flu vaccines to innoculate us against catching the flu.
- We have antivirals like Tamiflu and Relenza to treat flu (and even prevent flu).
- We have critical care resources for people who have pneumonia and respiratory failure - things like oxygen supplies, ventilators, sterile IV fluids, etc.
- While flu is caused by a virus, the main way the disease kills is by making people vulnerable to secondary bacterial infections. Unlike 1918, today we have antibiotics to treat bacterial infections.
- Flu hits the elderly the hardest, but the elderly today are healthier, stronger, and better nourished than ever before.
- In 1918, the spread of the flu virus was aided by crowded, unsanitary conditions.
All of that sounds very reasonable and very reassuring. But it's very shallow. And as in religion and politics, superficial thinking can lead to wrong conclusions.
Not enough to go around
There's an extremely fundamental flaw in assuming we can mute a severe pandemic with vaccines, respiratory products, and antibiotics - namely, we don't have enough of those things.
A pandemic brings a surge of illness onto a population. We don't have enough "surge capacity" to meet such extraordinary demand. Not enough hospital beds and not enough medicines and medical supplies.
Hospital administrators are frank about it; their facilities would be overwhelmed. See comments here and here, for example.
In some cases, remedying the shortages experienced during a surge event is not practical. For example, how do you solve the temporary need for more medical staff during a pandemic? (One idea: reactivate retired medical professionals. Would that be enough?)
In some cases, time is against us. It would take years to manufacture enough of some products.
Pandemic flu vaccines: a math lesson
To illustrate the quandaries, look at vaccines. A vaccine is probably the best defense against an infectious virus. Each vaccine is developed to match a particular strain of virus. Since flu viruses frequently develop new strains, we have to wait until a human-adapted strain emerges before we know what to target with a vaccine. In other words, a new human flu virus is circulating - a pandemic is underway - before we can begin making a vaccine matched to that virus.
Not that it matters. Because we can't make enough anyway.
The Center for Infectious Disease Research & Policy (CIDRAP), citing the World Health Organization and published research, reports that in a "best case scenario" we could produce about 750 million doses of pandemic vaccine per year worldwide. (That assumes a single-dose monovalent vaccine containing 15 micrograms of antigen per dose - the same as for seasonal flu. More about that assumption in a moment.)
As it turns out, that production figure is too high, because current egg-based production methods are less efficient for H5N1 flu vaccines. So WHO estimates the maximum capacity is actually more like 500 million.
But that's not how many people we could vaccinate. For effective immunization against a new virus, it's widely assumed each person needs two doses instead of one (a primer shot + the regular shot). So 500 million doses would vaccinate 250 million people each year.
On top of that, some research indicates that each dose of a pandemic vaccine may need more antigen in order to elicit an adequate immune response - maybe 30 to 90 mcg instead of the standard 15 mcg. Obviously, if each dose uses more of the available antigen, you can't make as many total doses.
So maybe we would only have enough vaccine for 75 million people per year. Whatever the actual production, whether 750 million or 75 million, there are 6.5 billion people. You do the math.
Even if we worked some magic and had 13 billion doses on hand within a few months (two vaccines each for 6.5 billion people), how are we going to administer them? We would need 13 billion syringes, plus enough medical personnel and logistical planning to distribute and administer, let's say, 25,000 shots per MINUTE for a YEAR. (Which actually sounds doable to me. Coming up with enough vaccine and syringes is the problem.)
So what do we do? Here are two possibilities:
- Develop some new kind of "universal" flu vaccine which protects against all strains of flu and which is produced using a faster manufacturing process. There are researchers working on that, although they aren't expected to have tested and approved products ready for a few years. (Then you have to manufacture 13 billion doses.)
- Make as much vaccine as you can as fast as you can after the pandemic begins ... and allocate it to priority groups. Those groups might include: health care workers, law enforcement officers, fire fighters, military, truck drivers, utility workers, employees in the food production chain, people in certain age groups or with certain health conditions, and so forth. That makes sense. And that's what we expect will happen. But it means the vast majority of us will not get vaccinated. The World Health Organization and others have expressly stated that.
"Inadequate supplies of vaccines are of particular concern, as vaccines are considered the first line of defense for protecting populations. On present trends, many developing countries will have no access to vaccines throughout the duration of a pandemic." -WHO
With no less an authority than the WHO saying vaccines will be of only partial help during a pandemic, why do the pandemic naysayers try to assure us otherwise?
Ironically, with respect to flu vaccines, most of us would be no better off than people living in 1918 (when flu vaccines didn't even exist). It doesn't matter that we know how to make flu vaccines if we can't provide enough vaccine when and where it's needed.
Generally speaking, the same supply problem exists with other medical tools mentioned by the pandemic naysayers. We don't have enough oxygen supplies, ventilators, respirators, face masks, etc. For example, Dr. Michael Osterholm of CIDRAP noted in the July/August 2005 issue of Foreign Affairs that of the United States' 105,000 mechanical ventilators, some 100,000 are used during a routine influenza season. "In an influenza pandemic, the United States may need as many as several hundred thousand additional ventilators," Dr. Osterholm says.
Antiviral drugs like Tamiflu and Relenza are certainly valuable resources. But, here again, you run into the problem of having adequate supplies during a pandemic surge. Whatever supplies are available probably will be allocated to critical workers and the medically vulnerable. In addition, as I've explained in discussing personal Tamiflu stockpiles, the medicine must be administered quickly, perhaps within 24 hours. Timely distribution of the medicine may be a logistical problem.
In sum, for many medical products and treatments, "surge capacity" is the Achilles heel of pandemic response.
(Sidenote: The above vaccine estimates are rough because there are uncertain variables. For instance, how much H5N1 antigen will be needed per dose? Can we stretch the supply of vaccines by adding adjuvants, as some researchers are exploring? There are tradeoffs to consider, also. For example, if all flu vaccine production is shifted to producing a vaccine against a pandemic strain, we won't have vaccine for the non-pandemic strains that cause the usual annual flu. Pandemic scenarios are complicated.)
1918 influenza was a direct killer
What about the statement that the 1918 flu mainly killed by secondary bacterial infections which today can be treated with antibiotics? That's only partially true.
According to the World Health Organization, "As expected, many of the deaths in 1918 were from pneumonia caused by secondary bacterial infections. But Spanish flu also caused a form of primary viral pneumonia, with extensive haemorrhaging of the lungs, that could kill the perfectly fit within 48 hours or less." As for today's H5N1 "bird flu" virus, the WHO also notes, "So far, most fatal pneumonia seen in cases of H5N1 infection has resulted from the effects of the virus, and cannot be treated with antibiotics."
However, the WHO goes on to say there certainly may be a role for antibiotics in late-onset pneumonia: "...since influenza is often complicated by secondary bacterial infection of the lungs, antibiotics could be life-saving in the case of late-onset pneumonia. WHO regards it as prudent for countries to ensure adequate supplies of antibiotics in advance."
Note that last phrase: "adequate supplies of antibiotics in advance." Even for those cases where antibiotics could help, we again face the question of whether we'd have adequate supplies. Would there be enough antibiotics to treat so many sick people at once?
The bottom line on antibiotics: Yes, I suppose we should stockpile antibiotics; it sounds like we probably would need them. But treating secondary bacterial infections isn't the big worry in my mind. The big worry is this: What if we're faced with a flu virus that is so virulent it can DIRECTLY kill via viral pneumonia (not treatable with antibiotics)? Right now, that's what influenza A (H5N1) does to chickens. As prominent virologist Dr. Robert Webster describes it, "...this is the worst influenza I've ever seen in terms of its killing capacity in animals. You put it into chickens this afternoon, they're all dead tomorrow." (IMPORTANT NOTE: That's the effect from avian/bird strains of H5N1 in birds. We don't know what any future human strain of H5N1 might do. But the fact we're starting with such a virulent strain in birds is not encouraging. And the bird strain has killed more than half of the 250+ people it is known to have infected. Related: I explain the difference between "bird flu in birds" and "bird flu in humans" here.)
Thinking outside the norms; mortality among young adults
Next is the statement that flu hits the elderly the hardest, but the elderly today are healthier, stronger, and better nourished than ever before.
The pandemic doubters are thinking out of context. So they miss the point and come up with wrong conclusions. There are probably two instances of this in their comment about the elderly.
First, they seem oblivious (maybe they are) that one of the most noted traits of the 1918 pandemic was the unusual age distribution of its victims. While influenza mortality usually is highest among young children and the elderly, the 1918 flu pandemic had a dramatically high peak of deaths among young adults. For example, the mortality rate for the 20-29 age group in Boston was 175 times greater than normal! I've discussed this in more detail here.
Normally, young children and the elderly are more likely to die from the flu. But flu pandemics aren't normal. (Isn't that THE core message in all discussions about pandemics?)
Coincidentally, this shift is seen in the current H5N1 cases (although this is not a pandemic). In June, a WHO epidemiological analysis of all H5N1 cases since December 2003 showed the case-fatality rate was highest in persons aged 10 to 39 years.
(By the way, some economists wonder what the economic impact would be should a modern pandemic kill a large number of young adults in their productive prime.)
The second "out of context" aspect to the comment about the elderly concerns our tendency to think that developed countries are the norm. To say the elderly are healthier and better nourished today may be true in developed countries. But what about elsewhere? A new report in The Lancet estimates that 96% of the pandemic-related deaths from a 1918-scale pandemic today would take place in the developing world. (I don't know how accurate that is, but it effectively highlights the risk in developing nations.)
A related thought: "elderly" is a relative concept. Life expectancy for white males born in the United States back in 1920 was 56 years.
The world's no bigger, but the population has tripled
The pandemic naysayers say the spread of the flu virus in 1918 was aided by crowded, unsanitary conditions.
Those of us in the more developed countries may not realize it, but crowded, unsanitary conditions very much exist in many places today.
After the 1918 pandemic, the world population tripled in about 75 years. In 1918, there were 1.8 billion people. Today there are 6.5 billion.
According to the United Nations, 3.25 billion people live in urban areas. There are more than 425 city urban areas with a population of one million or more.
As to sanitation: in 2002, 1.1 billion people lacked access to improved water sources and 2.6 billion people lacked access to improved sanitation, according to WHO.
So we have 6.5 billion people, half living in urban areas, 17% of whom don't have clean water, and 42% don't have sanitary bathroom facilities.
That can't aid the spread of a modern flu pandemic?
A related claim is sometimes put forth, namely, World War I had brought hunger, poor sanitation, and stress - conditions which fostered the spread of the flu pandemic. This ignores the fact that the vast majority of the world's territories and populations were untouched by the Great War. (The war was fought primarily in Central Europe, western Russia, and the Caucasus, with relatively limited activities in a few other places.)
Misunderstanding the risk of a severe pandemic
So the pandemic naysayers are using doubtful logic. Here are some balancing counterpoints:
1918 was not necessarily a worst case
As I've reported elsewhere, a leading risk modeling company says its probabilistic model indicates the 1918 Spanish Flu pandemic was not a worst case. In fact, the model developed by Risk Management Solutions suggests there's a one in five chance we could see a pandemic even more severe than 1918.
Is the extremely virulent H5N1 bird flu getting a running start on becoming such a human pandemic? No one knows.
Taking a too-simple view of a complicated threat
With respect to the pandemic threat, the naysayers seem to assume that conditions - from medical and scientific to economic and societal conditions - are markedly more advantageous today than in 1918. I'm not sure that's the case (at least, they've failed to persuade me) and I think the situation is far more complicated than these observers understand or admit. In particular, I don't think they appreciate how the "surge capacity" bottleneck will hamper our pandemic response.
I also think we can't afford to make big mistakes in comparing 1918 with today. Our assumptions and assessments frame our pandemic planning and preparation activities (and determine whether we even think we need such preparations).
If you think I'm flatly mistaken in my assessment, please let me know. I want to be right about this - and I'm not past correcting myself.
Otherwise, I urge you: Don't fall into the trap of thinking we're beyond the reach of a severe pandemic. We aren't.
An ordinary world, an extraordinary event
There's an overriding principle which is key to understanding the need for pandemic planning: our ordinary way of life isn't made for such an extraordinary event.
Stated differently, in normal circumstances we're geared for a certain level or capacity of activity. Within typical ranges, every day we accomplish a certain amount of work, manufacture a certain amount of product, have a certain number of employees in the office or plant or school or field, interact with a certain number of people, travel from Point A to Point B in a certain amount of time, fly a certain number of planes in and out of a certain airport, and so forth. This is the ordinary flow of daily life.
How well will our structured lives fare in the possible mayhem of a flu pandemic? When the next pandemic "stresses the system," how well will the system respond? That will be determined, in great part, by the degree to which we are flexible and resilient, can cushion ourselves, can adjust our capacity ("surge capacity"), and can reallocate resources in near real-time (days, not weeks).
In this post, I've applied this principle only to our medical resources - because my aim was to respond to the pandemic naysayers. Basically, the naysayers only talk about the direct medical possibilities. That's as deep as they go. It's logical that they look no further because they don't think there is any "further." Why give any thought to what to do in a flood if you think there's no chance of getting more than three inches of rain (at most)? They stop short because they think there's no real potential for any serious pandemic. But there is. There's even more medical impact than they acknowledge. I'll address those impacts (which you should consider in your planning) in subsequent posts.
But first, I want you to see a prime example of pandemic naysaying. For that, we'll turn to a guest editorial carried by Fox News last week. It's an eye-opener, of sorts.
UPDATE: Subsequent posts on (1) medical supply chain, (2) demographic differences, and (3) ripple effect on commerce and daily life.
This post is part of a series:
- You're right, it's not 1918. Is that good or bad?
- Now vs. 1918: Looking beyond the obvious
- Now vs. 1918: Looking beyond the obvious - Ripples
- Now vs. 1918: Looking beyond the obvious - Demographics
RELATED POSTS:
- You could have said that before the 1918 pandemic, too.
- Thinking about uncommon things.
- "Low probability" does not mean "never happens."
FOOTNOTE:
Population statistics are from The World at Six Billion, United Nations, 1999. [70kb .pdf]