Migrating birds spread bird flu? Japanese and Korean bird flu strain match

Main Category: Bird Flu / Avian Flu
Also Included In: Flu / Cold / SARS
Article Date: 21 Mar 2004 - 0:00 PDT

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Bird flu of Japan, S. Korea match / Officials believe migrating ducks may have carried virus from Korea.

The bird flu virus detected in South Korea was confirmed Thursday to be almost genetically identical to that of cases found in Japan, which indicates the disease was spread by migrating birds, according to an analysis by the National Institute of Animal Health (Japan).

The institute in Tsukuba, Ibaraki Prefecture (Japan), said more than 99 percent of the genetic sequences of each virus matched.

The Agriculture, Forestry and Fisheries Ministry (Japan) said it was highly likely that recent cases were caused by wild birds that migrated from South Korea to Japan because bird flu cases were found in western Japan and the timing coincided with outbreaks in South Korea.

The analysis signals the first time a relationship between a strain of bird flu detected in Japan and that of another country has been confirmed. It also is the first data to indicate a likely route of contamination.

After obtaining in mid-March a sample of the virus that caused the South Korean bird flu, the institute ran an analysis of it against samples of the virus detected in poultry farms in Yamaguchi, Oita and Kyoto prefectures.

In mid-December, bird flu was detected in mainly central and southern South Korea after the H5N1 strain was discovered at a poultry farm in the country.

In January, a case was confirmed at a poultry farm in Yamaguchi Prefecture, which was followed by similar discoveries in Oita and Kyoto prefectures. Samples taken from sites where bird flu was detected were identified as the H5N1 strain, and all were almost genetically identical.

An expert said ahead of the release of the findings: 'It's likely that a virus spread to the three prefectures from one place of origin. There also is a possibility that migrating birds, such as ducks, passed the virus to small birds, which then infected chickens at the poultry farms.'

Japanese government studies continue

Agriculture, Forestry and Fisheries Minister Yoshiyuki Kamei told reporters Friday that the bird flu virus appears to have a well-defined route of infection, and that the government would further study the matter.

'We'll proceed with discussions following results of epidemiological and wild bird studies, among others, conducted by institutions such as the Environmental Ministry,' he said at a press conference after a Diet session.

Based on results from an analysis of the current strain of the epidemic, there seems to be a defined route of infection, he said.

The agriculture ministry plans to pick a team of specialists next week to study the virus infection route.

From:
http://www.yomiuri.co.jp/newse/20040320wo32.htm