WSN/33 H1 in Fatally Infected Korean Swine Lungs
Recombinomics Commentary
April 28, 2005
New data is coming out of South Korea indicating WSN/33 sequences are now being detected in fatal swine infections. These new sequences are beginning to diverge from the WSN/33 sequence at GenBank as well as the two H1 isolates previously described. Two new H1N1 viruses have been isolated. WSN/33 sequences have also been PCR generated from lung tissues from fatal WSN/33 infections, including 3 aborted fetuses.
The fatal infections are on different farms in several provinces in South Korea. Partial sequences on the H1 have been obtained from two viral isolates as well as seven lung tissues. The new sequences are all unique from the two deposited swine H1 sequences (A/swine/Korea/S10/2004(H1N1) and A.swine/Korea/S175/2004(H1N1)). Analysis of approximately 600 bp in HA identifies 2 or 3 polymorphisms in the viral isolates not present in the 2004 isolates. The two polymorphisms shared between the two viral isolates can also be found in several of the PCR sequences (one polymorphism is in 6 of the 7). However, the PCR sequences show more diversity, with up to nine polymorphisms not found in any of the four viral sequences. However, most of the PCR sequences have several polymorphisms shared between the PCR sequences.
All sequences are clearly related to WSN/33. The homology is over 99% and the 3 nucleotide deletion in WSN/33 is also in all 9 sequences. Isolation of virus and sequencing of additional genes will determine how many avian genes are in these isolates. The new data increases the number of WSN/33 H1 sequences in pigs in Korea to 11 from 2.
11 different H1 WSN/33 sequences in swine on farms in many provinces in South Korea is a clear public health concern. The H1 in WSN/33 is human and should be fully transmissible to and between humans. Moreover, since WSN/33 is from 1933, those born after 1933 will have limited immunity.
WHO has made declarations that these sequences are lab errors and has written a press release indicating they had better things to do, yet they have failed to offer any evidence that the WSN/33 deposited at Genbank were due to lab error, other than citing a disputed virus shipment. The latest data include PCR analysis of lung tissue, which did not involve virus isolation and only two of the seven sequences match each other, reducing the likelihood of contamination. None of the sequences are exact matches of WSN/33, or the previously deposited WSN/33 H1 sequences, but all are over 99% homologous to each other and WSN/33.
There has been no attempt by WHO to explain this data, other than hand waving about lab error and issuing a statement that they had better things to do.
It has been over six months since the sequences were deposited at Genbank, and over five months since WHO was notified of a potential serious public health hazard. Their half hearted efforts at resolving this issue are scandalous.
WSN/33 has spread and evolved while WHO tried to prove it did not exist.
Pigs are dying with WSN/33 in the lungs.
Action is long overdue.