Information received on (and dated) 5 Feb 2008 from Dr Thomas Sit,
assistant director, Inspection & Quarantine, Agriculture, Fisheries
and Conservation Department, Cheung Sha Wan, Hong Kong, Hong Kong (PR China)

Summary
Report type: immediate notification
Start date: 18 Nov 2007
Date of 1st confirmation of the event: 5 Dec 2007
Report date: 5 Feb 2008
Date submitted to OIE: 5 Feb 2008
Reason for notification: reoccurrence of a listed disease
Date of previous occurrence: January 2007
Manifestation of disease: clinical disease
Causal agent: highly pathogenic avian influenza virus, serotype H5N1
Nature of diagnosis: laboratory (advanced)
This event pertains to the whole country

New outbreaks

Outbreak 1: Tuen Mun Park, Hong Kong
Date of start of the outbreak: 3 Dec 2007
Outbreak status: continuing (or date resolved not provided)
Epidemiological unit: not applicable
Species: wild species
Susceptible: 100
Cases: 1
Deaths: 1
Destroyed: 0
Slaughtered: 0
Affected population: a little egret (_Egretta garzetta_) found dead

Outbreak 2: Tuen Mun Park, Hong Kong
Date of start of the outbreak 18 Nov 2007 Outbreak status: Continuing
(or date resolved not provided)
Epidemiological unit: Not applicable
Species: wild species
Susceptible: 100
Cases: 1
Deaths: 1
Destroyed: 0
Slaughtered: 0
Affected population: a little egret (_Egretta garzetta_) found sick;
it died the next day.

Summary of outbreaks
Total outbreaks: 2
Total animals affected
Species: wild species
Susceptible: 200
Cases: 1
Deaths: 1
Destroyed: 0
Slaughtered: 0

Outbreak statistics
Species: wild species
Apparent morbidity rate: 1 percent
Apparent mortality rate: 1 percent
Apparent case fatality rate: 100 percent
Proportion susceptible animals lost*: 1 percent
* Removed from the susceptible population through death, destruction,
and/or slaughter

Epidemiology
Source of the outbreak(s) or origin of infection: unknown or inconclusive.

Epidemiological comments
This species is common and present all year round in Hong Kong. The
majority is resident but migrants have also been recorded in all seasons.

Local poultry farms are routinely under a constant monitoring and
surveillance programme involving serological and virological testing
and have individual farm biosecurity plans, which include bird
proofing of all sheds. All chicken farms are routinely vaccinated
with inactivated H5N2 vaccine and each batch of chickens has 60
unvaccinated individually identified sentinels, which are monitored
over the production life of the batch.

An intensive surveillance system is in place on all poultry farms,
poultry markets, pet bird shops, park birds, and wild birds in Hong
Kong. To date, no spread detected.

Diagnostic test results
Laboratory name and type: Department of Microbiology, University of
Hong Kong (local laboratory)
Species: wild species
Test: gene sequencing
Test date: 5 Dec 2007
Result: positive

Laboratory name and type Tai Lung Veterinary Laboratory, Hong Kong
(National laboratory)
Species: wild species
Test: haemagglutination inhibition test (HIT)
Test date: 5 Dec 2007
Result: positive

Species: wild species
Test: real-time reverse transcriptase/polymerase chain reaction (RRT-PCR)
Test date: 5 Dec 2007
Result: positive

Species: wild species
Test: real-time reverse transcriptase/polymerase chain reaction (RRT-PCR)
Test date: 5 Dec 2007
Result: positive