[note: One thing that I thought would be interesting would be to pull up posts from the archive and this post has been one floating in the back of my mind for quite a while. I’ve been wondering what would be the best format, and this is is my current idea, though it is not set in stone. I’ve deleted the comments, cleaned up the links (though many of them are broken, but the urls are cleaned up so you can find them on the wayback machine if you put your mind to it), and some other anal-retentive sort of stuff. Comments on the format or suggestions for other posts to put up here are warmly welcomed!
by hilzoy
It’s Pandemic Flu Awareness Week, so I thought I’d write a Pandemic Flu Awareness Post. Actually, a couple of them. This one is on general background and a few hints for personal preparedness; the next one will be on governmental responses and related issues.
Background: The CDC says that “the reported symptoms of avian influenza in humans have ranged from typical influenza-like symptoms (e.g., fever, cough, sore throat, and muscle aches) to eye infections (conjunctivitis), pneumonia, acute respiratory distress, viral pneumonia, and other severe and life-threatening complications.”
*** Update: According to the WHO, the symptoms of the strain of avian flu we’re concerned about are:
“Most patients have initial symptoms of high fever (typically a temperature of more than 38°C) and an influenza-like illness with lower respiratory tract symptoms (Table 3). Upper respiratory tract symptoms are present only sometimes. Unlike patients with infections caused by avian influenza A (H7) viruses, patients with avian influenza A (H5N1) rarely have conjunctivitis. Diarrhea, vomiting, abdominal pain, pleuritic pain, and bleeding from the nose and gums have also been reported early in the course of illness in some patients. Watery diarrhea without blood or inflammatory changes appears to be more common than in influenza due to human viruses and may precede respiratory manifestations by up to one week. One report described two patients who presented with an encephalopathic illness and diarrhea without apparent respiratory symptoms.” [End of Update]
The strain of avian flu we’re worried about — H5N1 — is an unusually nasty strain, and it is also unusually good at leaping across species boundaries. For the last two years, it has been spreading and changing in ominous ways. Revere at Effect Measure has a good summary:
“Starting in 1996 in southern China, it moved to Hong Kong in 1997, where it infected a number of people. After a hiatus where no infections were reported, it reappeared in 2003 in Hong Kong, swept into southeast asia where it has infected over a hundred people killing half of them, become entrenched in western China and eastern Russia and Kazakhstan, been found in wild birds in Mongolia and is poised to enter Europe (if it hasn’t done so already).”
And here’s a good timeline from Nature. (Note: the numbers of reported cases are probably low: it’s not as though every time someone either displays flu-like symptoms or dies after having them, people check for avian flu. We have probably missed both milder cases that were passed off as normal flu and deaths where no one thought to check, or had the resources to do so.)
Bird flu normally occurs in birds, not people. In order for a pandemic to occur, the virus has to change in ways that allow it (1) to infect humans, and (2) to be transmitted from one human to another, and (3) to be transmitted from one human to another not just once in a blue moon, but efficiently. We have certainly passed the first step: there have been around 116 cases, and over half of the people infected have died. We have probably passed the second, although it’s harder to be absolutely sure, since (alas) we can’t just ask the virus where it came from. It is also spreading to new animal species, including various migratory birds; and might have shown up recently in domestic ducks in Romania. We are hoping that the third shoe — efficient human-to-human transmission — won’t drop.
Michael Osterholm, Director of the Center for Infectious Disease Research and Policy, wrote in Foreign Affairs:
“The signs are alarming: the number of human and animal H5N1 infections has been increasing; small clusters of cases have been documented, suggesting that the virus may have come close to sustained human-to-human transmission; and H5N1 continues to evolve in the virtual genetic reassortment laboratory provided by the unprecedented number of people, pigs, and poultry in Asia. The population explosion in China and other Asian countries has created an incredible mixing vessel for the virus. Consider this sobering information: the most recent influenza pandemic, of 1968-69, emerged in China, when its population was 790 million; today it is 1.3 billion. In 1968, the number of pigs in China was 5.2 million; today it is 508 million. The number of poultry in China in 1968 was 12.3 million; today it is 13 billion. Changes in other Asian countries are similar. Given these developments, as well as the exponential growth in foreign travel over the past 50 years, an influenza pandemic could be more devastating than ever before.”
If the virus does learn how to transmit itself rapidly from human to human, we’re in for trouble. As noted above, a little over half of the people known to have contracted it during the current outbreak have died. Estimates of how many people might die in an avian flu pandemic vary widely:
“Nabarro also made several missteps in his initial news conference at the UN on Thursday, including straying far afield from the WHO’s estimate of the number of deaths a new pandemic might exact. He suggested between five million and 150 million people might die.
Less than 24 hours later the Geneva-based WHO reeled back in Nabarro’s estimate, saying its own longstanding projection of two million to 7.4 million excess deaths was more likely. The official WHO estimate was calculated using a mathematical model based largely on the Hong Kong flu of 1968, the mildest pandemic of the last century.”
Nabarro is in charge of pandemic preparedness at the UN; as noted, the WHO numbers are based on a mild pandemic, and are probably low. (Extrapolating the mortality rates from the 1918 pandemic to today’s population yields a prediction of 180 million to 360 million deaths globally.) But all these numbers are more or less well-founded guesstimates; the one thing we can be fairly certain of is that if a pandemic hit, a lot of people would die.
Moreover, if the virus does acquire the capacity for efficient human-to-human contact, it is more or less a given that it will appear in this country, whatever travel restrictions we put in place. Once upon a time, humans and the viruses they carry traveled by foot or by horseback, and most people stayed very close to home. In those days, epidemics spread more slowly. Nowadays, however, viruses can and do hop from continent to continent via jet aircraft and their human passengers. (A world in which lots and lots of people travel to lots and lots of places very quickly is a very, very convenient world to live in, if you happen to be a virus.)
The Department of Health and Human Services predicts that a severe pandemic would sicken 90 million Americans; that half of those would seek medical care; that 8.5 million would need to be hospitalized, 1.3 million of them in ICUs; that 639,000 would require mechanical ventilation, and that 1.9 million Americans would die.
The problems only begin with the death rates, however. Recently, hospitals have been consolidating, reducing the number of normally unused beds. Unused hospital beds can be viewed in several ways. From the point of view of hospital administrators trying to save money, they are inefficiencies. From the point of view of public health planners contemplating a pandemic, however, they are surge capacity: the extra beds that would allow us to deal with a sharp rise in the rates of disease. If a pandemic hits, we will need extra beds for millions of people, and right now, we don’t have them.
Likewise, according to Osterholm, “In the United States, for example, there are 105,000 mechanical ventilators, 75,000 to 80,000 of which are in use at any given time for everyday medical care. During a routine influenza season, the number of ventilators being used shoots up to 100,000. In an influenza pandemic, the United States may need as many as several hundred thousand additional ventilators.” If the DHHS is right to estimate that 639,000 people would need to be put on ventilators in a severe pandemic, the number of people who would require ventilators is over six times the number of ventilators we actually have, and over thirty times the number not already in use.
“If it were determined that several cities in Vietnam had major outbreaks of H5N1 infection associated with high mortality, there would be a scramble to stop the virus from entering other countries by greatly reducing or even prohibiting foreign travel and trade. The global economy would come to a halt.”
Just think about the impact of suspending trade with, say, Indonesia, Vietnam, Thailand, and China. And while you’re thinking, recall that we have largely moved to ‘just in time’ ordering and production, which is wonderful in a lot of ways, but particularly ill-suited to dealing with massive and global disruptions in supply chains. It’s enormously difficult to figure out what, exactly, would happen as a result of this. However, while dire predictions aren’t obviously right, I’d be a lot happier if they were obviously wrong, and I don’t think they are.
In addition to all this, if a pandemic hits we will have to deal with panic and its effects. Think back on the anthrax episode: it was awful, but the chances of any individual (with the possible exception of Congresspersons, their staff, and DC postal employees) encountering an anthrax letter were remote. Despite this, however, normally sane people made a run on Cipro, bought duct tape, and so forth. Think of SARS: it was much more serious than the anthrax scare, but, according to Wikipedia, 8,069 people got sick and 775 died. This is orders of magnitude fewer than would die in an influenza pandemic, and yet the combination of public health measures and fear caused enormous disruption, including an estimated $40 billion in costs to the Asian Pacific region.
So, basically: that’s why people are very, very worried about this.
Personal Preparedness
So: what can you do to prepare? I’m not a public health expert (though I did ace Epidemiology); you can find the recommendations of people who are at some of the links below. Because I’m not an expert, and because I tend to low-tech, cheap precautions, I’m going to restrict myself to some common-sense recommendations, most of which are things it would probably be a good idea to do anyway.
First, get your annual flu shot this year. The flu shot does NOT confer protection from avian flu. Nonetheless, it’s a good idea. For one thing, avian flu might decide to strike during the flu season; if this happens, you do not want to get both flus in a short period of time. Even the normal flu is a pretty serious illness, and it weakens the body. You do not want to confront avian flu in a weakened state. For another, influenza viruses can mingle with one another when one organism — you, for instance — is infected with both. When this happens, it can lead to new strains that can infect people; and this would be a Bad Thing That We Should Try To Prevent. Thus, flu shots.
Second, stock up on things you might need from a drug store. For obvious reasons, drug stores tend to attract sick people. If there’s an infectious pandemic, you will not want to go to the drug store more than you have to. Thus, keeping a larger than usual supply of all those drug store things on hand would probably be a good idea.
(There are people who recommend stocking up on everything, as if we were expecting a war. I normally have extra food around, mostly because I hate having to go to the supermarket when I don’t feel like it. I am not acquiring lots more. That may just be a reflection of the fact that I usually have a fairly high tolerance for risk and a low tolerance for reactions that strike me as panicky, though.)
Third, if you need to have some medical procedure that you have been putting off, have it now. You do not want to develop a serious need for a hospital in the middle of a pandemic.
Fourth, there are some supplies that will predictably be bought up when people panic. Among them are respiratory masks (NIOSH-certified N-95 masks, says the WHO). Opinion is divided on them: they are definitely recommended for symptomatic nursing mothers, and health care workers, but for the rest of us, it’s less clear. The reason to get them is that one way flu is spread is “via virus-laden large droplets (particles >5 µm in diameter) that are generated when infected persons cough or sneeze; these large droplets can then be directly deposited onto the mucosal surfaces of the upper respiratory tract of susceptible persons who are near (i.e., within 3 feet) the droplet source.” Masks block these droplets. (Note: because airborne flu viruses travel in “virus-laden large droplets” that people cough up, the fact that the virus itself is smaller than the holes on most masks is unimportant. Stopping the droplets is the key.) The reason not to use them is, as far as I can tell, that they might be overkill for those of us who are neither health care workers nor nursing mothers. It is worth thinking about whether you will wish you had some later, and if so, buying them now. (They run around $1-2 apiece; if you buy them, buy enough to last a while. As I said, NIOSH-certified N-95 masks are recommended. And while I haven’t tried them myself, I hear that having an exhale valve makes a real difference: the downside of sealing airborne particles out is, alas, sealing your hot muggy breath in.)
Another thing it would be worth thinking about getting is alcohol-based towelettes (the sort you carry around with you.) They kill viruses, and if you’re not near a sink, they can be handy. Alcohol-based are supposedly best; here’s a CDC list of ingredients and their efficacy at killing viruses and other things. If you think of other things that are likely to become unavailable as soon as a pandemic starts, and that you will want to have, buy them now.
Fifth, one of the most important things you can do in a pandemic is simply to wash your hands, wash them often, and wash them right. (Note to any compulsives out there: ‘often’ does not mean hundreds of times a day.) It really makes a big difference; you can see why if you simply reflect on how many of the possible ways in which a virus might try to get into your lungs involve your hands, and how well a serious washing would disrupt them. A blog called Aetiology puts it well:
“Wash your hands. It’s not sexy advice, I admit. But ever since Semmelweis, it’s been the smartest thing a public health professional can advise. And really, many of us still don’t do it correctly. It is recommended to wash with soap and running water for at least 20 seconds. I know that when I’m in public restrooms (and I work within a hospital building!), I very rarely see people wash that long. So, be a bit more contientious when you wash. Teach your children to do this as well: have them count to 20 or sing their ABC’s while washing their hands. If you’re not around a faucet, hand sanitizers with 70% ethanol are also effective. (To my knowledge, Triclosan, the other common ingredient in hand sanitizers, has not been proven effective at killing viruses–so watch the ingredients and stick to alcohol).
If you’re sick, please, please, please stay home. Adults are contagious for 5 days and children for up to 21 days after becoming sick. Don’t go and expose others when you’re coughing, sneezing and hacking all over the place.
Avoid touching your eyes, nose, and mouth. Again, think about how many times you do this every day. This is one way influenza can enter a body. Also, re-train yourself not to cover your mouth with your hands when you cough: use a tissue, or the crook of your arm—-something that won’t come into contact as often with surfaces, or with other people.
Resources:
- The Flu Wiki has a lot of good resources. It has: a resource page with a lot of really good links; a scientific information page; a preparedness page, and lots more.
- The CDC Avian Flu page. It has links to all sorts of topics. One that I did not find at first, and that might be really useful to someone, is the CDC guidance for pregnant woman and new mothers.
- WHO Avian Flu page
- The Center for Infectious Disease Research and Policy’s Avian Flu page
- Two good articles from Foreign Affairs: 1, 2
There are also some very good blogs that write on this topic: Effect Measure, Recombinomics, and Aetiology (new to me, but its pandemic preparedness series is very good.)
If you have any other suggestions, either for links, preparedness, or just questions, chime in.
If we only knew what was coming
Kind of interesting that in the 20 years since this was originally posted, in the case of a pandemic we (the OECD countries) have developed the ability to formulate a vaccine and manufacture a billion doses in under a year.