January 20, 2005
Bird flu may evolve into epidemic: WHOTopics: Health Issues
in my Jan 10 post entitled "Avian influenza continues: Is their a tsunami of avian influenza brewing?" and in several earlier posts(such as here and here) on the same subject dating back to Dec 10, 2004 entitled "Bird Flu(Avian Influenza) Outbreak Fears Spark Action - Up To 100 Million People Could Die," I have been warning of the developing threat of an avian influenza epidemic. The following snipets are from my earliest post on the potential epidemic, in which I wrote:
(...) ...according to "Proc Natl Acad Sci U S A. 2004 May 25;101(21):8156-61. Epub 2004 May 17," the hemagglutinin of recent human isolates has undergone significant antigenic drift. Like the 1997 human H5N1 isolates, the 2003 human H5N1 isolates induced the overproduction of proinflammatory cytokines by primary human macrophages in vitro, whereas the precursor H5N1 viruses and other H5N1 reassortants isolated in 2001 did not.
(...) This acquisition by the viruses of characteristics that enhance virulence in humans and waterfowl and their potential for wider distribution by infected migrating birds (unlike the precursor H5N1 viruses and other H5N1 reassortants of 2001) are causes for renewed pandemic concern.
(...) I predict that we are going to hear much more about this in the near future.
It appears that the future I spoke of may be now much closer, and the preventative concern and action that I expressed a need for may soon be too late. Avian influenza (bird flu) kills people, and lots of them.
ABCNewsonline (Australia) Jan 21
The bird flu virus endemic in Asia appears to be evolving in ways that increasingly favour the start of a deadly human influenza outbreak, the World Health Organisation (WHO) warns.
In its latest report on preparedness for an influenza pandemic, the organisation says the situation "may resemble that leading to the 1918 pandemic", which killed more than 40 million people.
The United Nations health agency fears that the H5N1 bird flu virus could mutate into a deadly human form.
It is again urging countries and drugs companies to speed development and production of a vaccine.
The death toll in Asia stands at 38 - 26 in Vietnam and 12 in Thailand - from the latest outbreak.
However, there are so far no signs that the virus is being transmitted easily between people.
But the agency says that recent epidemiological and laboratory studies reveal unusual features that "suggest that the virus may be evolving in ways that increasingly favour the start of a pandemic".
The WHO has forecast a potential death toll of 2 million to 7 million as a "best case scenario" for an outbreak, which it says is overdue.
The last one, which claimed between 1 million and 4 million lives, was in 1968.
The deadly virus has become "hardier", surviving several days longer in the environment.
Evidence also suggested that the virus is expanding its range of mammal hosts, including captive tigers and experimentally-infected domestic cats.
Migratory birds and domestic ducks show no symptoms but excrete the
highly pathogenic virus, indicating an "important silent role in
- Reuters - End item
Avian influenza affects most types of birds and occurs in epidemics on poultry farms. The fatal disease is named "highly pathogenic avian influenza" and is caused by influenza A virus subtypes H5 and H7. The natural reservoir is the migratory waterfowl that occasionally infects domestic poultry.
For FAQs about avian influinza go to the Ministry of Health site in Singapore.
From the same site, "Is there anyway to treat avian influenza?
Answer: At present, there is no human vaccine effective against the H5N1 influenza virus. Currently available vaccines do not protect against human disease caused by the H5N1 strain. However, two pharmaceutical companies will be starting clinical trials on a H5N1 vaccine soon.
Yale New Haven Health is a good source for learning more about "Preventing a Pandemic: Understanding Avian Influenza"
Posted by Hyscience at January 20, 2005 11:06 AM
Articles Related to Health Issues:
- Bird flu may evolve into epidemic: WHO - Jan 20, 2005