Information received on 24 December 2004 from Dr Chang-Seob Kim, Chief Veterinary Officer, Animal Health Division, Ministry of Agriculture and Forestry (MAF), Gwacheon:

Date of the report: 24 December 2004.

A heightened awareness campaign is being implemented from November 2004 to February 2005 to prevent reintroduction and resurgence of highly pathogenic avian influenza (HPAI). As part of this campaign, sero-surveillance focused on breeding and broiler ducks, considered as major reservoirs and important risk factors for HPAI, is being conducted both in farms and slaughterhouses, and virological tests are being carried out on faeces sampled in migratory birds´ habitats.

During this heightened sero-surveillance, avian influenza antibody-positive samples were detected on 1 December 2004 in a breeding duck farm in Kwangju Province through agar-gel precipitation (AGP) test carried out by the Kwangju Provincial Veterinary Laboratory.

Following this finding and subsequent pathogenicity test, the National Veterinary Research and Quarantine Service (NVRQS) identified this case by 23 December 2004 as low pathogenic avian influenza subtype H5N2, through AGP test, haemagglutin inhibition test, neuraminidase inhibition test, PCR⁽¹⁾, embryo inoculation and haemagglutinin cleavage site sequencing. The NVRQS identified H5N2 subtype through serological tests and PCR on 22 December, and on 23 December confirmed low pathogenicity with a weak response in embryo inoculation test and with the sequence of the amino acid at the haemagglutinin cleavage site of PQKETK/GLF.

Approximately 13,000 ducks were being raised in this farm and no clinical signs were found, there was no drop in the egg production rate, nor were there any deaths.

In view of the fact that this is the first detection of H5N2 subtype in the Republic of Korea, the Ministry of Agriculture and Forestry implemented stamping out of the infected flock in accordance with the HPAI contingency plan, and will further expand sero-surveillance to adjacent farms and epidemiological contact farms as well as conduct an investigation into the source of virus.

(1) PCR: polymerase chain reaction