Jun 25, 2008
Bird Flu Flap
I’m not entirely convinced that bird flu (avian influenza) is going to be the next big emergent disease that will wipe out thousands, if not millions, of people across the globe. SARS, after all, had nothing to do with avians, nor does HIV, and certainly not malaria, tuberculosis, MRSA, Escherichia coli O157, or any of dozens of virulent strains of disease that have and are killing millions of people.
There are just so many different types of host within which novel microbial organisms and parasites might be lurking, just waiting for humans to impinge on their marginal domains, to chop down that last tree, to hunt their predators to extinction, and to wreak all-round environmental habitat on their ecosystems, that it is actually only a matter of time before something far worse than avian influenza crawls out from under the metaphorical rock.
In the meantime, there is plenty to worry about on the bird flu front, but perhaps nothing for us to get into too much of a flap over, just yet.
According to a report on Australia’s ABC news, researchers have found that the infamous H5N1 strain of bird flu (which is deadly to birds) can mix with the common-or-garden human influenza virus. The news report tells us worryingly that, “A mutated virus combining human flu and bird flu is the nightmare strain which scientists fear could create a worldwide pandemic.”
Of course, the scientists have not discovered this mutant strain in the wild, they have simply demonstrated that it can happen in the proverbial Petri dish.
Meanwhile, bootiful UK turkey company – Bernard Matthews Foods – has called for an early warning system for impending invasions of avian influenza. A feature in Farmers Weekly Interactive says the company is urging the government and poultry industry to work together to establish an early warning system for migratory birds that may carry H5N1 avian flu. “Armed with this knowledge, free range turkey producers would be able to take measures to avoid contact between wild birds and poultry.” That’s all well and good, but what if a mutant strain really does emerge that also happens to be carried by wild (and domesticated birds) or, more scarily by another species altogether? Then, no amount of H5N1 monitoring is going to protect those roaming turkeys.
While all this is going on, the Washington Post reports that the Hong Kong authorities announced Wednesday (June 10) that they are going to cull poultry in the territory’s retail markets because of fears of a dangerous bird flu outbreak. H5N1 virus was detected in chickens being sold from a stall in the Kowloon area and 2700 birds were slaughtered there to prevent its spread. In closely related news, the International Herald Tribune has reported that there has been an outbreak of bird flu in North Korea. “Bird flu has broken out near a North Korean military base in the first reported case of the disease in the country since 2005, a South Korean aid group said Wednesday.” But, note, “since 2005″, which means it happened before, and we didn’t then see the rapid emergence of the killer strain the media scaremongers are almost choking to see.
Finally, the ever-intriguing Arkansas Democrat Gazette reported, with the rather uninspiring headline: Test shows bird flu in hens. Apparently, a sample from a hen flock destroyed near West Fork, Arkansas, tested positive for avian influenza. A little lower down the page we learn that the strain involved is the far less worrisome H7N3. So, avian influenza is yet to crack the US big time. Thankfully.
Some good points Cindy. Things are never clear cut. Yes, of course H5N1 is constantly mutating, as are all “organisms”, those that reproduce most efficiently will be the ones that survive, natural selection in action. A highly virulent and lethal human pathogen will not necessarily persist in a host population, of course, and whether or not a mutant H5N1 is the next big epidemic to which we succumb is certainly open to debate, it could just as easily mutate into a H2H form but be less lethal and so merge into the general strains of influenza to which we are exposed each year, killing thousands as opposed to millions. Meanwhile, some yet unknown pathogen emerges from a different niche and begins infecting people in ways that could not be foreseen (viz HIV), what about an airborne version of a virus with similar effects to HIV, that would certainly cap anything an influenza virus can do…
H5N1 hasn’t mutated into a pandemic strain, but it is mutating.
We are seeing human deaths from both bird-to-human and from human-to-human transmission. The human-to-human transmission does not appear to be sustained, but that may be because the Indonesians are passing out Tamiflu to every potential case.
The Indonesians are saying that at least 25% aren’t linked to poultry. That doesn’t necessarily mean human-to-human transmission. We know both cats and dogs have been infected with H5N1 in Indonesia – either could have been the source of human infection as well, but there aren’t reports of large numbers of dogs or cats dying.
Over the past few months the majority of cases in Indonesia have been in clusters, this is a big change over the past threee years.
There have been mutations that enable the virus to more easiy latch onto the cells in the human respiratory tract .
And there have been mutations that make the virus resistant to antiviral drugs – or at least Tamiflu. I don’t know if you can really say that this advances a pandemic because we do not have enough Tamiflu to prevent a pandemic to begin with, but it makes attempts to slow the spread more difficult and has obvious impact during a pandemic.
Our preparedness is pathetic as well.
Yes, 1918 was originally avian and mutated into a human transmissable form at a time of international conflict and poverty. H5N1 is yet to mutate. Percentages are cruel. Deaths are tragic.
The 1918 influenza pandemic was an avian virus. The fact that SARS, HIV, malaria, tuberculosis, MRSA, etc aren’t avian disease doesn’t influence whether or not H5N1 will cause a pandemic.
Since H5N1′s current case fatality rate is 60% worldwide (with antiviral meds) and 80% in Indonesia (with antiviral meds) where the virus seems to be most active, I can’t think of much that would be worse.
Ya, I think I would be more afraid of ourselves than I would be of Bird Flu. I’m sure we will wipe eachother out before the next strain for birdflu takes me out. :). Good post, and very informative. Thanks for taking the time to look up all those sources.