I would welcome opinions and facts about what our level of concern should be regarding the appearance of bird flu in humans. Specifically I am interested in the following:
1. Are world health agencies, including our own, preparing adequately?
2. How real is the threat that this could develop into a pandemic?
The book by John Barry, The Great Influenza: The Epic Story of the Deadliest Plague in History certainly is on my mind.
Posts: 440 | Registered: Oct 2001
| IP: Logged |
posted
I don't know much updated information about the bird flu, but if you want to learn some scary things about the spread of Lyme disease and West Nile, you really ought to read Lab 257. I checked it out of my local library. I think I'll buy my own copy now..
posted
I know that they recently found a strain of avian flu in some chickens here in town. It was a form of a flu that was harmful to humans in Asia, but the form that was here was harmless. Just the same they slaughtered all or very nearly all the chickens, turkeys, et cetera in the Faser Valley. Which, of course was horrid for many of our farmers, but that was the only sort of harm that it did here. Regarding West Nile, what I've been hearing is that it really only poses a threat to the very young and the elderly, but I'm not a doctor or any sort of expert, so don't take that at face value coming from me.
Posts: 1158 | Registered: Feb 2004
| IP: Logged |
quote: Regarding West Nile, what I've been hearing is that it really only poses a threat to the very young and the elderly,
Well, whoever told you that is very wrong. My nearest neighbor, who is the same age as me (43) and a specimen of good health, not overweight, and works hard as a rancher, very nearly died from it. And another lady in our area, also just in her 40s DID die of it.
posted
Most of the encephalitis cases in my online support group were from West Nile Virus, and not very young or elderly.
Posts: 10890 | Registered: May 2003
| IP: Logged |
posted
It's my opinion that somebody (the government, the universities, pharmaceutical companies) needs to be working on a better way to make flu vaccine. We may be able to halt a pandemic of a deadlier strain of flu if we can make vaccine quickly enough, although it's not going to spread slowly from Asia like it used to. Now that infected people can get on planes, I suspect that once it really gets going in Asia (human to human transmissible), we'll only have days before large outbreaks begin here.
Posts: 3546 | Registered: Jul 2002
| IP: Logged |
posted
I find it difficult to sift through all the information and news reports that seem fragmented at best on the subject.
I was hoping some one on here could direct me to a good source of information about the recent asia reports of bird flu crossing to humans and how serious authorities are viewing the occurence.
In other words, separating information from disinformation about the subject.
posted
Good article that does nothing to lessen my apprehension concerning the potential of human to human transmission.
Posts: 440 | Registered: Oct 2001
| IP: Logged |
posted
Dave - I was wondering if you began this post due to a news article that was in the newspaper yesterday here. Seems the Wichita paper picked it up from the wire, from the Denver Post, even though it is datelined as Atlanta:
posted
Why can't antiviral drugs be made available to the public? They might save many many lives if they were. They are the only thing we know of that decreases the mortality rate, but must be administered early in the course of the disease to be effective. Once a pandemic hits, health care is going to be difficult if not impossible to come by. Doctors offices and hospitals will be overwhelmed, and possibly deadly to visit in any case since full of infected people.
Also, supposing we have a year or two left before it happens, the immediate increase in sales would prompt manufacturing and distribution chains to ramp up production and throughput, meaning there would be more capacity when the inevitable enormous spike in demand hits.
Seems like a win/win deal to me.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
fugu, duckling, why dost thou sigh? At so tender an age thy great wisdom already tireth of sharing itself with thy brethren? <grins and pokes>
So in your scenario where a few people keep it back for themselves, that results in fewer deaths overall than one in which it's widely available with a greater chance of resistance forming? And who decides who gets it?
The computer modeling scenarios I've seen (Scientific American) show that the most effective use of both vaccines and antivirals will occur to delay only (not prevent) the eventual spread of the virus to all parts of the globe, and they can most effectively be used at the very start of outbreaks, which are expected to be in rural Asia where there is only an extremely limited healthcare infrastructure.
I believe both antibiotics and antivirals should be made available to the public, along with information and warnings about their use. Because of increased distribution and production capacity that will bring about, this will mean that more is available overall when the crisis comes. I believe that healthcare professionals do people a great disservice when they treat adult humans as though they were children or cattle, to have decisions made for them because they're unable to choose rightly for themselves. Especially because they know full well that they can't possibly treat everyone. If you know you can't care for everyone then isn't it unconscionable to act to prevent them caring for themselves?
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
It wouldn't work, ak. There are four approved antivirals on the market in the US, and of them the bird flu is already resistant to two. If you bombard the entire population with the remaining antivirals you'll select for the resistant strains and, ironically, speed up the process of a pandemic.
Granted, if they were used at the start of a pandemic they would probably buy some time. But that's wonderful only in theory because by the time you've identified a super resistant, highly contagious strain odds are it's already too late. Nevermind the nightmare of getting an entire population to medicate themselves when told and neither before nor not at all.
Seriously. The absolute best thing you can do, bar nothing, is be healthy in all aspects of your life. Even if nothing happens, you win. That's about as good of a win/win as you can hope for.
Posts: 3243 | Registered: Apr 2002
| IP: Logged |
posted
They are definitely going to give the doctors and healthcare workers antivirals. That makes sense since they have such a higher risk of infection, plus they are needed so badly.
It's not that the influenza viruses "already" developed resistance to those other 2, is it, BtL? My understanding from my reading on the CDC, HHS, and WHO site is that those antivirals were never effective against influenza to begin with. The two that are block the receptors that allow the virus to 1) enter and 2) exit the cells. Now it's possible that strains will arise that are resistant to those two antivirals but exactly how is that worse than not using them to begin with?
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
I'm not an expert on this matter but I believe what Bob is trying to say is by giving the general population the antiviral treatment this far in advance of the actual pandemic the greater the chance of a regular flu virus will develop resistance to it. So when the pandemic does come all it would take is for someone to be infected with the drug resistant flu virus and the bird flu and thus we would be left with no treatment to stop this new super bird flu.
Posts: 796 | Registered: Mar 2005
| IP: Logged |
posted
I'm not sure that's what Tatiana is suggesting, though. Tatiana, do you mean that we should have the ability to buy antiviral drugs (such as Tamiflu, which has been shown to be effective against avian flu) so that when the pandemic hits, there will be enough to go around? If people were smart about the use of the drugs, and only used them if a serious, deadly flu pandemic occurred, would that be better than running out of antiviral drugs because there was not enough demand and too little was manufactured?
Posts: 3546 | Registered: Jul 2002
| IP: Logged |
Also, the healthcare system is certain to be woefully insufficient (in terms of scheduling doctor visits, available hospital beds, writing and filling prescriptions, and so on) once the pandemic hits. If we have stockpiled drugs in advance (and they have a shelf life of a decade) as well as any other needful supplies then there is something we can do for ourselves and our families besides sit by and watch while 70% die.
The information about when to use the drugs could be included in the package, and taught verbally as well at the time the drugs were bought. From everything I've read, I think this could save many lives, possibly millions.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
I am a biology professor folks so I'll try and help. First off, I'm no virus expert, I work on plants, but here goes...
The flu virus like all viruses are parasites, but what makes this one (influenza) such a bugger is the fact that it has a high rate of mutation. That's what enables it to move from species to species in a manner quite similar to moving from host to host. This propensity towards mutation provides it with the evolutionary potential to adapt to anitvirals relatively easily. Wide spread over the counter antivirals might actually make the problem worse since they would be a new selction pressure on this organism(?) that is quite capable of evolving. Here's how...
Consider a wild type (normal) flu virus that infect person A. As the infection progreses this person's cells begin to make more flu virus. Many of the new flu viruses are bound to be mutants, that is, variants on the wild type. Some of these may be better at one part of the life cycle, while others are better at another part. [Don't forget that the process of mutation in random so you should expect some to be bad at a life cycle part as well.] However, those that become "better" will likely also end up being "worse" at something else. Why? Well, the thing about Nature is that she's on a budget. If the virus is good at something new, invariably it will be so at the cost of doing something else more poorly. We call this the "trade-off," and it is one of the more important ideas in biology. Here how this might be relavent in our hypothetical case here. Let's say that one of the mutants shows some degree of resistance to the anitvirals purchased over the counter. This selective agent (antiviral) will favor the new mutants while the wild type suffers and does not produce as many new viruses. The mutant will come to dominate the infection. The resistant mutant will be the one that is spread to new hosts. The problem with this is that when this mutant virus infects person B it will continue to mutate and repsond to the selection pressures in this new environment.
Well, where does the trade off come in? Suppose that the resistance to the antiviral only provided the selective advantage in the presence of the anti-viral molecule and in the abscence of it there is a cost to the virus carrying the mutation where it cannot rapidly complete its life cycle (quite common). As long as person B is not taking the antiviral the mutant viral won't do so well and either the immune system beats it, or the wild type emerges as the dominant form again and we are no worse off than when we started. However, suppose that over the counter flu-meds are ubiquitous and that person B takes a different anitviral (perhaps a new class of molecule). The virus will have to reposond to this one as well if it is to survive. The virus has the potential to start stacking resistance genes and become stronger and stronger. This is essentially what HIV does and what some bacterial forms have done--think MRSA (multiple resistance staphlococcus aureus). The more we push the critter, the greater the potential it has to become an unmanageable pest. By allowing the MD's to control the meds, they can control the rate at which the virus can adapt and perhaps keep it at bay longer.
So why did antivirals work on Polio and small pox? The answer seems to lie in the fact that these bugs do not mutate as quickly. If the mutation rate is low then you can beat it. The way to do so is to deprive the parasite it's host. This is why we immunize children. If we can innoculate children before they are exposed to the pest, then the immune system can marshal its forces sufficiently to beat the infection before they become symptomatic and infectious. Many of you take flu shots and it helps keep you from getting the flu (or so you think). What it does is prepare your immune system for the most likley flu virus of the year. In fact, you actually may get infected, but your immune system beats it before you are symptomatic. It is not a permanent fix because the flu virus has many mutants and it is impossible to develop a vaccine for all of them. In other words it is not possible to deprive this masterful bug of its hosts. In fact, this is one of the reasons why the influenza virus is so successful since it can even jump to new species in search of hosts.
In short (in this long missive) voer the counter access to anitvirals will likley spped up the rate of adaptation and drive the flu virus to become more a nd more resistant and ultimately more and more deadly. Perhaps so deadly (beyond prudence) where it kills off it host entirely. Spooky stuff!
Sorry about the length.
Posts: 514 | Registered: May 2005
| IP: Logged |
posted
Oh, and I'm not sure if you should be worried. It depends on your level of exposure. But, I worry about all viruses.
Posts: 514 | Registered: May 2005
| IP: Logged |
posted
It seems that the latest computer modeling studies are showing that both prevaccination with an H5N1 vaccine, even if not the exact strain that causes the pandemic, and saturation with antivirals used prophylactically, are effective strategies in fighting the potential pandemic.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
My guess is that this would be practically impossible. The costs of the application would far exceed the benefits.
quote:Originally posted by Tatiana: It seems that the latest computer modeling studies are showing that both prevaccination with an H5N1 vaccine, even if not the exact strain that causes the pandemic, and saturation with antivirals used prophylactically, are effective strategies in fighting the potential pandemic.
posted
The computer modeling studies are being carried out by different flu experts, including Emory University biostatistician Ira M. Longini, Jr.
Nancy J. Cox, chief of the Influenza Branch at the U.S. Centers for Disease Controls and Prevention says that such modeling enables officials to get a handle on how much antiviral would be required to control an outbreak.
World Health Organization spokesman Dick Thomson says the agency will convene experts to talk about implementing a concrete plan based on the modeling studies.
So it seems that the models are being taken seriously.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
What is your preferred plan? That we try to stay healthy in general and do nothing specific to combat bird flu? The flu seems to prefer healthy young people at this point, and to kill over half of those infected, though the latest clusters show that it's spreading out more into all age groups and starting to become better at human to human transmission, meanwhile the mortality rate is dropping to around 1/3 which helps some but also means easier spreading since survivors tend to infect more people than corpses. It still means hundreds of millions of deaths worldwide are to be expected.
I suppose doing nothing at all is one option, but I don't feel it's a very wise course.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
Ya know, when any corporations' minutest desire to maximise profit by even the minutest amount overides species survival -- eg Disney's sharkfin soup -- I'm approaching the point where I wouldn't care if it weren't for a pandemic's effect on children who don't have any control over their elders' behaviour.
posted
Turns out that the 1918 Great Influenza was a bird flu which mutated into being directly infectious between humans. "...changes in just 25 to 30 out of about 4,400 amino acids in the viral proteins turned the [bird flu] virus into a killer [of humans] ...the 1918 virus' hemagglutinin protein differs in just two critical amino acids from the protein of a typical avian flu virus."
posted
So far I've read very little except the National Geo article and a few online. It does have me scared.
Posts: 2711 | Registered: Mar 2004
| IP: Logged |
posted
I'm a little more worried about Bush demanding that he be given control of the military to use to quarantine parts of the country in the event of an outbreak.
Posts: 21898 | Registered: Nov 2004
| IP: Logged |
quote:Scientists have recreated the 1918 Spanish flu virus, one of the deadliest ever to emerge, to the alarm of many researchers who fear it presents a serious security risk.
quote:When injected into mice, it quickly took hold and they started to lose weight rapidly, shedding 13% of their original weight in just two days. Within six days, all mice injected with the virus had died.
quote:Publication of the work and the filing of the virus's genetic make-up to an online database followed an emergency meeting last week by the US National Science Advisory Board for Biosecurity, which concluded that the benefits of publishing the work outweighed the risks.
posted
It's important for us to know why the 1918 pandemic was so very virulent compared to the other two pandemics we had in the last century. If we understand what it was genetically that caused the Spanish flu H1N1 it to kill so many millions of people, we would know for sure whether the Bird flu H5N1 had the same qualities.
According to this NPR item that AJ linked me to today, the virus was all bird flu genes and no human flu genes. That's very interesting because it means the virus came about through mutations of the bird flu H1N1 virus rather than reassortment when human flu plus bird flu genes were mixed in the cells of an animal who was sick with both at once. That makes me feel better, in a way. Perhaps it will take several mutations before our current H5N1 avian flu virus can be good at human to human transmission.
We need to know for sure what mutations caused the H1N1 Spanish flu virus to be easily transmissible from person to person, and compare that to the H5N1 current Avian flu viruses we are sampling from the sick people in Asia. So to me it makes a lot of sense to recreate the actual organism and study how it works.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
quote: So to me it makes a lot of sense to recreate the actual organism and study how it works.
quote:but let's just hope that it's protected
I agree it is important to understand it, but it does need to be protected. I am sure we have much worse cases of Ebola in labs, HOWEVER we do not publish how we make killer viruses for the world.
The article states:
quote: The genetic sequence is also being made available to scientists online, a move which some fear adds a further risk of the virus being created in other labs.
It is the making the process available online that worries me.
Posts: 2445 | Registered: Oct 2004
| IP: Logged |
posted
lem, the reason pandemics are so deadly is that they are from a NEW strain of flu that nobody has any immunity to. H1N1, the Spanish flu virus that killed so many in 1918, is no longer new. All or nearly all the common flu viruses circulating yearly these days are of the H1N1 subtype. So if this did get loose or if someone recreated it and spread it for evil purposes, it would be no worse than any ordinary flu year. The scary one is now H5N1 since nobody has any immunity to that.
Even H5N1 is not of any use as a weapon, though, since it will spare no country over the face of the entire earth. There's no way to target it towards one group of humans and spare others. Once it's loose (in a form that spreads easily between humans) everyone is equally vulnerable, from heads of state to newborns, rich and poor, everyone. Access to respirators and antiviral drugs can increase someone's survival chances from 30% to 50%, perhaps, but is that a gamble anyone would want to take? I don't think we need fear its use as a weapon.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
quote: Originally posted by mackillian: You know, the whole "Bird flu" and "screechowl" connection is just TOO easy to make. --------------------------------------------------------------------------------
Ha! I was tellin' myself, "I will not snicker...I will not snicker..."
space opera
I am doomed to go through my entire life as an unwitting straight man. Posts: 440 | Registered: Oct 2001
| IP: Logged |
Printer-friendly view of this topic
![[Wink]](wink.gif)
