- “H7N9: A Tale of Two CDCs” (April 2013)
- “H7N9 Risk Communication: Candor but No Push to Prepare” (May 2013)
When H5N1 bird flu started jumping from sick poultry to humans in 2004, and spreading to Asia, Europe and Africa in 2005 and 2006, most flu experts truly felt that a human pandemic might well be imminent and could well be devastating. Their early communication reflected this fear, though in a somewhat muted form.
No bird flu pandemic has occurred yet. And we had a mild swine flu pandemic in 2009.
Every step of the way, the experts were scoffed at as alarmists by some in the media, government, and the public.
This history can’t help but influence their current communication about the new big flu thing – H7N9.
But officials and experts are not just cowed about raising a new alarm because there hasn't been a bird flu pandemic yet, or because the swine flu pandemic turned out mild. Many of them also feel much less certain that a bird flu pandemic is imminent or inevitable than they did in 2004, when lethal bird-to-human cases were spreading in an unprecedented way, and keeping flu experts awake at night.
Now they have ten years of that precedent – lethal bird-to-human cases keep happening with H5N1, with no noticeable increase in human-to-human capability. So that initial “Oh my God” feeling that prevailed among experts in 2004 has attenuated. And because of the ten years of no H5N1 pandemic, they don’t have the same strong hunch that an H7N9 pandemic could easily be imminent.
Fortunately, at the same time that many people were accusing the experts of scare-mongering, many others took the alarm to heart – and of course were falsely accused of panicking. Despite the scoffing, a fair amount of resources were allocated for planning and research.
Now there is something new under the sun. H7N9 seems to jump more readily from birds to humans than H5N1, though still not easily. It causes severe illness and death in many of the humans – and it doesn’t even make the poultry sick. This new pattern has produced another “Oh my God, who knew this could happen?” feeling among experts – but without the same sense of pandemic imminence as in 2004.
It took about three years for the first 250+ human cases of H5N1 to be confirmed, in the presence of sick poultry that could be identified and culled. It has taken about 10 months for about the same number of human H7N9 cases to be confirmed – in the absence of sick poultry.
But experts already have ten years experience, from H5N1, that this doesn't guarantee that a pandemic is imminent, although they know it might be.
The hardest thing for experts to communicate, and for media to convey, and for the public to grasp, is that an avian-launched pandemic might realistically happen tomorrow or never, and might realistically be catastrophic or no big deal. It’s like constantly balancing on the fulcrum of a seesaw.
And whatever is conveyed, no matter how nuanced, if the outcome goes in the other direction, people will remember the experts as having overly alarmed them, or as having failed to warn them.
Our most important message to experts and officials: The public health harm, and the political harm, done by over-warning versus under-warning are not equal. While it can be costly either way, it is nearly always better if they over-warn than if they under-warn. As with a smoke alarm, it’s “darned if they do, and damned if they don’t.”
And even if the experts can communicate and the public can grasp all of that, it leaves open what to do about it, given all the other potentially catastrophic but highly uncertain events in the offing.
The very best but extremely difficult risk communication strategy is to convey the potentially catastrophic magnitude of a flu pandemic, alongside the entirely uncertain probability of such a terrible pandemic. And then the task is to share the dilemma about what to do about such an uncertain but horrible prospect.
The numbered points below cover much the same ground. Feel free to mix and match as you think best.
- Certainly public health agencies are leery of “warning” the public about a novel flu virus or coronavirus that hasn’t yet proved itself dangerous on a public health level. As you point out in your email, H5N1 hasn’t done much in recent years to justify the pandemic fears back in the day, and the pandemic we did get – swine flu – was so mild it provoked widespread charges of hype, especially in Europe. Officials aren’t afraid of scaring people; they’re afraid of being accused of trying to scare people. And they’re afraid of provoking still more cynicism. They don’t have much credibility left when it comes to infectious disease warnings, and they’re trying to husband what they have.
- H7N9 is causing human cases in China quickly right now. But this second H7N9 season isn’t yet significantly more serious, cumulatively, than the first H7N9 season last year – which abated without constituting much of a threat to public health. So far, H7N9 is still hard to catch from a bird and harder to catch from another person. It’s mainly dangerous to people who frequent live bird markets in China, and only to a very few of those people – so far. So the general public health risk of what’s currently going on is negligible.
- Insofar as there’s something to worry about, it’s the potential risk of what might happen, not the current risk of what’s happening. The #1 fear is of course that H7N9 acquires the ability to pass easily from human to human, launching a pandemic – and potentially a devastating pandemic if it remains roughly as deadly as it is now to the few who have caught it. Other fears: that H7N9 becomes highly pathogenic in poultry and threatens the food supply; and that H7N9 acquires the ability to pass easily from poultry to humans, making poultry dangerous (which would also threaten the food supply) and perhaps launching a “panzoonotic.”
- As far as we know, the experts have no basis for calculating or estimating the probability of these scenarios. H7N9 turning disastrous is not like an asteroid strike: a high-magnitude risk of calculable low probability. This is a high-magnitude risk whose probability cannot be estimated with any confidence. The same is true for H5N1, MERS, and some other dark-horse novel viruses.
- This is extremely hard to talk about – it would be hard to talk about even if officials weren’t afraid of being accused of alarmism. It is hard to communicate a clear, balanced message: Nothing scary (in public health terms) has happened so far; things could happen that would be very scary and we don’t know how likely they are. So officials are mostly not talking to the public at all.
- Media stories about these novel viruses aren’t getting big play (as you know better than we do!). But they’re out there. The networks, the wires, and the major papers all run stories from time to time, usually leading with a bunch of new cases or a fatality in a new location. Consumers of these stories aren’t getting much help from the experts to put them into context.
- At least some people are surely getting the impression that something new is happening in recent years: lots of novel viruses. It’s hard to know if it’s really new, or if we’re just better at surveillance. Some may be “learning” that more and more such threats mean there’s more and more reason to worry that one or another will launch a disaster. Others may be “learning” that more and more false alarms mean there’s less and less reason to worry. Public health experts aren’t sure themselves which lesson makes more sense, so they’re leaving the public (and miscellaneous outlier “experts”) to draw their own conclusions.
- Preparedness for experts means mostly improvements in surveillance and vaccine manufacturing capacity. What should preparedness mean for society and for individuals? Should people be urged to stockpile food and meds for their other illnesses in case a pandemic wreaks havoc with supply chains? Should employers cross-train so there aren’t so many irreplaceable people whose illness or death would make it impossible for the organization to function? These are questions few if any officials are willing to raise, wishing to avoid accusations of scare-mongering.
Copyright © 2014 by Peter M. Sandman and Jody Lanard