More H5N1 Mis-matches in Indonesia
Recombinomics Commentary
November 29, 2007
The bird flu vaccine for Medan for example, could not be compared with giving of the vaccine that was same in Java. Giving of the wrong vaccine, said NIDOM, even could change the vaccine into the trigger increasing the strength of the bird flu virus.
Along with the NIDOM explanation, [Audio ounce Demand]. NIDOM said that must be attention now and no longer to the poultry that was regarded as the virus bearer. But must think about how the pattern of the spread of the bird flu virus to humankind.
With the Tropical Diseases Centre Universitas Airlangga Team, NIDOM was researching anywhere the bird flu virus could spread after from the poultry, the cat and the pig.
The above translation notes that H5N1 is rapidly evolving in Indonesia, and the reservoir remains uncertain. Although the H5N1 in Indonesia is clade 2.1, many sub-clades have evolved, and the new subclades are frequently not well represented in bird isolates.
These match failures were seen shortly after the first human isolates were sequenced. Most were from Java and did not match poultry isolates. The isolates had a novel cleavage site and the first related sequences were found in a cat from Indramyu. Although additional matches in isolates from birds were subsequently found, the H5N1 evolution in birds trailed the human sequences.
New human H5N1 sequences have not been released since early January, and the most recent sequences again form a new branch not well represented by the avian sequence. Recently a large number of bird sequences from 2006 and 2007 were released, and the closest match to the most recent human isolates from the end of 2006 and beginning of 2007 was a quail isolate from Bantul, A/quail/Indonesia/Bantul1631-40/2006.
These match failures again suggests that many of the human infections are linked to reservoirs not well represented by current isolates, and more extensive testing of other sources, including wild birds is warranted.
The H5N1 is evolving into multiple sub-clades, which are also not well represented in current vaccines. Vaccine mis-matches can also drive H5N1 evolution. Therefore a broader testing of potential H5N1 reservoirs and release of recent human H5N1 samples would be useful.
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