Efficient H5N1 Transmission in Medan Indonesia?
Recombinomics Commentary
May 17, 2007
The Ks assumption flattest bird flu strengthened because of the patient still the neighbour Nefri, the patient who died resulting from bird flu. Ks lived in the Delapan Village, Desa Medan Estate, Kecamatan Percut Sei Mr, Kabupaten Deli Serdang, only 100 metre from the Nefri house.
The above translation describes the location of the latest H5N1 suspect case, which is just 100 meters from the latest confirmed H5N1 case in Deli Serdang, a suburb of Medan, North Sumatra.
Suspect or confirmed H5N1 cases near Medan are of concern, because of last year's Karo cluster, which involved 8 family members near Medan, almost exactly one year ago. 7 of the 8 family members died, and the spread of H5N1 involved human-to-human-to-human transmission.
The relationship of the H5N1 linked to the latest confirmed case with the H5N1 isolated from the Karo cluster is unclear, because samples from the past 15 confirmed cases in Indonesia have been withheld. Three samples from two patients have been sent to Tokyo for analysis, but it is unclear if these samples are from the two latest cases, both of whom have been on Sumatra. The penultimate case was also transferred to Adam Malik hospital in Medan, and the two confirmed cases have died.
The neighbor of the latest case is not stable, and is hospitalized with bird flu symptoms.
The sequences from the Karo cluster had the consensus HA cleavage site, RERRRKKR, which is unusual for human cases in Indonesia. The vast majority of the human H5N1 sequences from Indonesia had a novel HA cleavage site, RESRRKKR. The Karo sequences however, had a number of polymorphisms that were also found in Qinghai sequences. The timing of the latest cases may signal new acquisitions from migrating birds.
Sequence matches between human and bird sequences in Indonesia have been poor, yet there have been no public swine or wild birds sequences, so the situation in Indonesia remains unclear.
The symptoms in the latest confirmed cases raise concerns over an increase in transmission efficiencies. Sequences from the past two confirmed cases on Sumatra, and the status of the latest suspect case would be useful.
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