Investigation of Human and Bird Flu in Swine on Korean Farms
Recombinomics Commentary
May 7, 2005
At this point WHO should be well aware of the fact that the human H1N1 WSN/33 sequences in swine on Korean farms are quite real. The sequences at GenBank are not from 30 sequence files uploaded in error and they are not contamination from WSN/33 in the Sang Seo lab in South Korea. The case of WSN/33 is not closed.
WHO is now aware of the 9 new WSN/33 sequences from fatal infections of swine, including 7 sequences from PCR analysis of lung tissue. The origin of the sequences is unknown, but a full investigation is long over due. This process requires South Korea to notify the WHO that there is a problem with influenza infections in swine. These infections appear to involve Korean bird flu H9N2 sequences, as well as H1N2 and H1N1 sequences (WSN/33).
The H1N2 sequences have been described previously in swine in South Korea, as well as the United States. The WSN/33 sequences were first deposited at GenBank in October, 2004. The H9N2 sequences are most closely related to Korean avian sequences of 2004, which are distinct from 2003 sequences, suggesting these infections are recent. The H1N2 sequences were first reported in the United States in 2001.
WSN/33 was first isolated in London in 1940 in mouse brains following passage of WS/33 through mice. The first sequences at GenBank were from the early 90's. Thus, the time and location of WSN/33 infection is unclear. Therefore, an investigation of WSN/33 sequences in various labs around the world, as well as swine in the United States would help determine the origin of the WSN/33 sequences in swine on farms in Korea.
.