Global Avian Influenza Network for Surveillance (GAINS)

Wildlife Conservation Society
www.wcs.com

WCS Global Health Program

The laboratory results from the avian influenza surveillance samples collected by the WCS team in 2008 were received from the University of California Davis in February. Of the 2,763 samples collected from wild birds in Mongolia, 143 tested positive by RT-PCR for matrix sequences indicating the presence of avian influenza sequences.  

Only one sample tested positive for H5. This was collected from a Red-necked Stint (Calidris rufficollis).  The bird was a juvenile and was caught in a mist net at Bayannuur near Daschinchilen, Bulgan aimag on 20 August 2008. The bird showed no signs of ill-health when captured, and was marked and released. This bird was approximately 2-4 months old at the time of capture and likely hatched in the tundra of northern Russia. At this stage there is no reason to indicate that this virus was a highly pathogenic subtype.

The team did not detect any unusual mortality at Bayannuur during the two weeks at the site. WCS will, however, be investigating this sample further. The next stages of analysis will be to attempt to amplify HA and NA sequences from the H5-positive sample at UC Davis. If successful, the strands will be sequenced which should provide an indication of pathogenicity.  The frozen duplicate sample from this bird that is in Hong Kong University will also be submitted for viral isolation in an attempt to culture the virus.