Posted on 10/22/2004 6:42:19 PM PDT by Mother Abigail
A researcher from China's Harbin Veterinary Research Institute has today presented initial evidence that pigs from farms in parts of China have been infected with the H5N1 strain of avian influenza.
Pigs are known to be susceptible to infection with avian influenza viruses. However, natural infection of pigs with the H5N1 strain has not been previously reported.
In order to assess the implications for human health, it is important to know whether the reported infections in pigs are rare events, possibly caused by contact between pigs and wild birds. Wild aquatic birds, which are the natural reservoir of all influenza viruses, can carry the H5N1 strain without developing symptoms, and are known to excrete large quantities of the virus in their faeces.
A comparison of the H5N1 strain isolated in pigs with strains recently circulating in poultry populations in parts of Asia is needed to determine whether the virus is being passed directly from poultry to pigs. Evidence of direct transmission of H5N1 from poultry to large numbers of pigs would be of particular concern, as this would increase opportunities for a new influenza virus with pandemic potential to emerge.
Pigs have been implicated in the emergence of new influenza viruses responsible for two of the previous century's influenza pandemics. Pigs have receptors in their respiratory tract that make them susceptible to infection with human and avian influenza viruses. If a pig is simultaneously infected with both a human and an avian influenza virus, it can serve as a "mixing vessel", facilitating the exchange of genetic material between the two viruses in a process known as "reassortment". The resulting new virus, which will not be recognized by the human immune system, will have pandemic potential if it retains sufficient human genes to allow efficient human-to-human transmission, and if it causes severe disease in humans.
Confirmation of H5N1 infection in pigs would add complexity to the epidemiology of this disease, but needs to be viewed in perspective. During the peak of the poultry outbreak of H5N1 in Viet Nam earlier this year, extensive testing of pigs on farms where poultry were heavily infected failed to find evidence of infection in pigs. In addition, Hong Kong authorities regularly perform random testing for the H5 avian influenza virus subtype in pigs imported from mainland China. No infection in pigs has been detected to date.
While the 2001 World Series had the latest finish in baseball history, the 1918 series had the earliest. Both aberrations in scheduling were caused by world conflict - "the war to end all wars" in 1918, the war on terrorism following Sept. 11, 2001.
As the 1918 World Series was being played, America faced an outbreak of Spanish Flu. In what would be the worst pandemic since the Black Death of the 14th century, it took 500,000 lives in the United States and 21.64 million worldwide.
Because of the turmoil surrounding it, the 1918 World Series did not draw much attention. It opened Sept. 5 in Chicago with Ruth beating Hippo Vaughn 1-0 in one hour and 50 minutes.
It ended with Carl Mays winning 2-1 in Game 6 before a mere 15,238 at Fenway Park.
That finale was played Sept. 11 - a day of victory in 1918, a day of infamy in 2001.
ping
Well I'll be. Ain't that strange.
I love chaos! Strange attractors indeed.
FYI
Thank you for the ping. I had just finished reading the article, when I saw your alert.
This could make the ordinary yearly epidemic look mild.
The guy from the "Coast to Coast" thread predicted an influenza outbreak like 1918...hmmmm
http://www.freerepublic.com/focus/f-chat/1253947/posts
That's some sorta mineral water from the French Alps - no?
It is still early in the investigation. How widespread the the infection is will determine the level of concern, but this is not good news.
'Bout time we nuked 'em and sterlized 'em.
One of these times, the bug will get out of the box...
It`s just odd that the guy heard on Coast to Coast AM this morning predicted pandemic akin to 1918 and later they find THE strain from 1918. creepy.
None of us knows what's just around the corner.
Maybe nothing, maybe something.
26 tigers dead in a zoo in Chonburi, Thailand apparently from eating raw, infected, chickens.
I don't see why you say they found THE strain from 1918. H5N1 is an avian influenza. The actual 1918 strain, however, is being researched at the University of Washington.
A team of US scientists have demonstrated how miniscule changes to a current, relatively harmless flu virus can transform it into a disease as devastatingly deadly as the 1918 flu virus (Spanish Flu) which destroyed millions of human lives.
In an animal study (mice), the scientists added two genes to the 1918 strain (they had a sample).
The original sample never had any effect on mice. With these two added genes, the new virus killed the mice within days - as did the 1918 flu virus to humans.
You can read about this study in Nature, it was led by Dr Yoshihiro Kawaoka, Wisconsin University. He assured reporters that the studies were carried out under the strictest security.
Dr Yoshihiro Kawaoka said there are two genes which are key in the infection process. The scientists worked mainly on these two genes.
One of the genes regulates haemagglutinin (HA) production.
Scientists think HA is used by the virus to attach itself to its target cells (the cells it wants to attack/infect). Scientists are convinced the 1918 virus was so deadly because of HA.
When the team carried out post mortems on the infected mice (they had been infected via injections on the nose) they found that the virus rapidly entered their lungs, producing inflammation and haemorrhaging.
The scientists believe HA may also play a similar role with humans. However, they said their research can only prove this, so far, with mice.
Dr. Kawaoka said this research may help us asses the potential danger of new flu viruses more effectively.
Dr. Kawaoka, said "Once the properties of the (1918) HA gene that gave rise to its lethal infectivity are better understood, it should be possible to devise effective control measures and to improve global surveillance networks for influenza viruses that pose the greatest threat to humans as well as other animal species." (Nature).
It is thought the 1918 flu virus was a mutated bird flu virus that made the leap from bird-to-human to human-to-human contagion.
Scientists say it probably found its way there (to humans) by infecting pigs first. Pigs can get human flu viruses and bird flu ones and perhaps swap genes when the virus multiplies inside them.
The great concern today is what might happen with the current bird flu outbreaks that are taking place in some south east Asian countries. If they mutate and spread among humans (human-to-human infection) the result could be catastrophic.
Experts say the genetic difference between a giant flu killer virus and a relatively harmless one is very small - they are quite similar - meaning that the mutation does not have to be a big one.
Half of the world's population was infected with the 1918 flu virus, one billion people. It dwarfed the Black Death (the plague) of the Middle Ages.
Many say the 1918 flu pandemic brought about the end of the First World War.
As I recall, an Asian avian flu virus was shown to have spread between humans in an earlier outbreak, also there were some fatalities; can you confirm or debunk my recollection?
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