A Flu Pandemic?
Pedrito writes "Scientific American is running a story in this month's issue about preparing for a flu pandemic. What this article tries to convey is that a pandemic is definitely coming. Whether it's from the H5N1 strain (which would likely cause hundreds of millions of deaths) or another strain a few years down the road. There have been 3 other flu pandemics in the past 100 years. The 1918 strain being the worst, with 40 million killed. The reason H5N1 is being followed so closely is because it's already spread to people and because it's incredibly lethal (a roughly 50% fatality rate at th moment). Even if the fatality rate dropped to 5% when and if it mutates into an easily communicable form, it would be twice as deadly as the 1918 virus."
Whilst this sort of thing has happened before saying it's definitely going to mutate is an overstatement. The same kind of sensationalist journalism not to long ago likened mad cow disease to a new sort of plague with predictions of obscene death rates when in reality it was statistically low. It could end up the same for this with a few hundred people dieing over several years ... nothing huge is definitely going to happen.
M-O-O-N. This spells first post.
Here is a one-page, ad-free version of the article. Seriously, when articles are formatted like this, submitters should use the "printer friendly" version of the article as the submission.
The Discovery Channel will be having a special on about this at 10:00pm EST, it was on last night and I believe it was nearly a 60% fatality rate. In Holland they had to slaughter nearly 30 million birds (mostly chickens) because the disease spread there. The most cases and deaths have been reported in Vietnam, 41 deaths out of the total of 62. You might want to watch this special, it even talks about how they found out the 1918 flu was originally a complete avian strain, much like how this new one is.
Fear the turtle farming ninja!
I'm still waiting for SARS to get me, cos that's what I was told was going to kill me before. And then there was West Nile Virus. And we can't forget those killer bees that'll be here any day now. Shouldn't we all be dead from ebola by now, too? Or how about monkey pox?
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
I keep seeing these 50+% mortality figures being thrown around, which seems slightly misleading to me. Imagine if 100 people get a disease. 30 might get it asymptomatically. 60 might get the disease to such an extent that they're "sick" (feeling flu-ish, missing work, etc). 10 might get it to the extent that they wind up in the hospital. If 5 of those 10 die, what's the mortality of the disease? It might seem like 50% to a doctor treating these patients, but the actual number would be 5 percent.
Because we can only report mortality of cases which we actually see, health officials are already biased towards observing the most severe forms of the disease. With something like, say, HIV, or ebola, it might be safe to say that all reported cases = ALL cases. But with something like a strain of the flu, which people suffer to varying degrees, I'd guess there's some much larger number of cases that are simply never seen in hospitals.
Short subject line -- in the 1918 pandemic the young and healthy were often fine in the morning and dead by nightfall. Even in the more common situation where it took a few days to kill, it struck the young and healthy disproportionately harder.
The problem? An immune system has to be _reactive_. Your immune system has to develop sensitivity to the new virus and that takes some time. The usual flu strain isn't a problem since it's very similar to the strains we've already seen (in infection or innoculation) and our immune system can quickly respond. There's also a lot of natural selection going on over time -- a virus would rather see us miserable and contagious for a week than dead and non-contagious within a day.
But we have no natural immunity to an entirely new strain, and some can kill before our immune system can develop an effective response.
That's why older people faired better in 1918. They hadn't seen the same strain, but they had seen enough variety that they had a stronger initial response than their younger peers.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
But not too reactive. The suggestion has been made that the problem isn't that our immune systems don't react to H5N1, it's that it reacts too vigorously, as per, for example, this article, Bird Flu Triggers Immune System 'Storm'.
Michael T. Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota School of Public Health is quoted in that article as saying that this might be why the young and healthy get stricken more severely (presumably he's referring to H5N1, but perhaps that happened with the 1918 flu as well):
There's a reason that would limit the lethality of new mutant :
...
- The point of a virus is not killing its host, but making copies of it self.
- The lethality of H5N1 is a bad secondary effect.
- If a new mutant kills its host to quickly, it'll run out of hosts and wont replicate anymore.
Example :
- If one catch a new über-mortal flu
- brings it home
- infect familiy member
- the über-mortal flu kills very quickly and the whole family drops dead the same evening
- The virus will be "stuck" and won't be able to infect anyone else.
-> That's one of the reason we didn't see a Ebola pandemia
But, if it is a slower virus,
and the people survive at least a few couple of weeks (or don't die at all),
they will have plenty of time to go to work the next days, and transmit the flu to all co-workers, etc...
The kind of pandemia you see in movies, when some (hibernating/comating patient wakes up / austronaute lands / whatever else) and see everyone dead is not very likely.
The danger will be if a flu virus like H5N1 can both cross infect birds, but is almost harmless to them, and humans, and is highly lethal, then there's some chance of such a "everyone drops suddenly dead" scenario.
To put it in more Slashdot-friendly terms :
Imagine an internet worm.
If the worm crashes Windows immediatly after infecting the PC, even before having time to replicate and send copies to the whole Outlook addresse book,there's no way it could become widespread.
A few PC will crashes and that's the whole story.
But if the virus, silently installs backdoors/trojans/spywares and silently begins replicating, THEN you'll have a lot of infected boxen.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Factors working against us:
* As a whole, people do not get as sick as in previous generations. The constant fuss over cleanliness reduces the general health of the immune system because of its lack of exposure to many diseases.
* Vitamin deficiencies are not as rare as one might think; while scurvy is no longer common, most people in the civilized world consume processed foods, which generally lack vital nutrients. As such, their body mass is maintained or expanded, but the gains made in nutritional science have not, as a whole, trickled down very far into the general population.
* Palliative diseases are of little use against a virus that causes tissue death in the lungs, encephalitis, and destruction of tissue membranes due to necrosis and apoptosis. H5N1 appears to cause a broad-spectrum attack on the human body in ways that aren't helped by rehydration or salt balance.
* The vast majority of people may live in their own bedrooms, but are more likely to congregate in large, relatively cramped areas for work, school (especially school!), and purchasing. The rise of mass transit means that especially in urban areas, people are crammed together for long periods of time sharing the same air. For instance, in Tokyo, one person could infect sixty to a hundred people on the ride to the Akihabara district with one sneeze. Same in New York on the A, 4/5/6, 1/2, or 7 lines.
Furthermore, many more people live in apartments with central ventilation. One infectious person can thus infect dozens, even hundreds, of people with whom he has no direct contact.
* International and cross-continental travel is much more common, leading to the possibility of faster spread. If the virus has a long presymptomatic infectious period, one overnight flight from China could lead to an infection that spreads through half of San Francisco and hopscotches to New York within a matter of days, catching public health authorities off guard.
* A virus that spreads via aerosolized particles isn't as susceptible to sanitary conditions as many other diseases. It helps, but isn't as useful in preventative care as you suggest.
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the pen is mightier than the sword, the sword is mightier than the court, the court is mightier than the pen.