Pig tested H5N1 bird flu positive in Java in 2005

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H5N1 detected in pig in Banten (Java) in 2005

Also in April, a researcher in Jawa Timur detected H5N1 virus in throat swabs and
blood samples from a pig in Tangerang, Banten Province, by RT-PCR ( Reverse transcription-polymerase chain reaction) Inactivated RNA isolates were sent to Japan for confirmation, where eight fragments (HA, NA, PA, PB1, PB2, M, NP, NS) were sequenced.

The haemagglutinin (HA) gene of the isolated virus was a more than 98 percent match to samples taken from infected chickens and quail from Indonesia. The virus has been characterized as HPAI (based on the cleavage site structure).

The Ministry of Agriculture has conducted tests on pigs in several regions.
So far, only one area in Banten, in the western part of Jawa Island, has tested positive.


ftp://ftp.fao.org/docrep/fao/010/a0115e/a0115e04.pdf (p. 2)

 

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Re: Pig tested H5N1 bird flu positive in Java in 2005

H5N1 virus may be adapting to pigs in Indonesia


CIDRAP report (Center for Infectious Disease Research & Policy Uni Minnesota)
http://www.cidrap.umn.edu/cidrap/content/influenza/panflu/news/mar3109swine-jw.html

Mar 31, 2009 (CIDRAP News) ? Scientists report that H5N1 avian influenza viruses may be adapting to pigs, as evidenced by the finding that H5N1 viruses isolated from pigs in Indonesia were less harmful to mice than were H5N1 viruses from chickens.

An intermediate host
Pigs are seen as a possible intermediate host that can help avian flu viruses adapt to humans, because the epithelial cells in pigs' trachea can be infected by both avian and human flu viruses, the article notes. If avian and human viruses infected a pig at the same time, they could mix or reassort, giving rise to a novel strain that might be able to spread in humans. The flu pandemics of 1957-58 and 1968-69 were caused by avian-human hybrid viruses, though it is not known if they arose in pigs.

Prelude to a pandemic strain?
The authors offer this interpretation of their findings: "Since our swine strains were isolated from pigs with no apparent influenza-like symptoms, the decrease of pathogenicity in mice suggests that the H5N1 viruses may have lost their pathogenicity in mammals during replication in pigs. Given that for the H5N1 viruses to cause a pandemic, they would likely become attenuated in humans, becoming attenuated in mammals may be a prelude to the generation of a pandemic strain."

 

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Re: Pig tested H5N1 bird flu positive in Java in 2005

H5N1 Avian Virus Adapting to Pigs, Closer to Human Variation


4 April 2009 | http://www.digitaljournal.com/article/270449

The deadly H5N1 virus, a scourge among avian species in Asia, appears to have adapted to operate in swine populations, a report in the Archives of Virology finds

The H5N1 virus - a headline-producing species that regularly ravages avian populations throughout Asia - appears to have successfully mutated toward residence in pigs. While the pig variety may be less virulent than its avian-oriented cousins, it is acknowledged among virologists that the transference to the swine environment is a precursor to human infection.

The H5N1 viruses were isolated from pigs in Indonesia and were tested on mice. The pig-oriented variation was considerably less devastating to the exposed mice than the avian H5N1 species.

 

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Re: Pig tested H5N1 bird flu positive in Java in 2005

From source above

Pigs are a notable concern because they have cells in their trachea that allow for both avian and human influenza infections. Influenza species commonly trade information, and if pigs carry both human and avian strains at a given time valuable replication detail can be traded among the influenza species within the pig host - and new combinations can arise.