General information
Report type: Immediate notification
Started: 29 Jun 2024
Confirmed: 4 Jul 2024
Reported: 19 Jul 2024
Reason for notification: Recurrence of an eradicated strain
Date of last occurrence: 25 Jun 2024
End date: -
Disease: High pathogenicity avian influenza viruses (poultry) (Infection
with)
Causal agent: Highly pathogenic avian influenza virus
Nature of diagnosis: Clinical, laboratory
Genotype/serotype/subtype: H5N1
Event status: Ongoing
This event pertains to the country/territory.

Quantitative data summary
Outbreak location: Yulin, Taiwan, Taipei
Start date: 13 Jun 2024
End date: -
Total animals affected:
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Birds (domestic) / 53 140 / 9538 / 9538 / 43 602 / 0 / 0

Epidemiology
Source of event or origin of infection: Unknown or inconclusive
Epidemiological comments: This outbreak indicates the recurrence of
highly pathogenic avian influenza (HPAI) H5N1 subtype (clade 2.3.4.4b)
in 2 poultry farms in Chinese Taipei. The owner of these 2 farms
reported the situation to the local veterinary authority in Yunlin
County, and samples were collected on 29 Jun 2024. The samples were
sent to the National Reference Laboratory for diagnosis on 1 Jul 2024.
Clinical signs included increased mortality rates, reduced appetite,
and decreased egg production. The outbreak was confirmed as HPAI on 4
Jul 2024. Subsequently, 43 602 chickens were culled, and comprehensive
cleaning and disinfection were conducted on 6 Jul 2024. Farms within a
3-km (1.9 mi) radius of this location will undergo heightened
surveillance for the next 28 days.

Control measures at event level: Disinfestation, movement control,
stamping out, surveillance outside the restricted zone, surveillance
within the restricted zone, zoning
To be applied: Screening

Diagnostic test results
Test name / Laboratory / Species sampled / Number of outbreaks sampled
/ First result date / Latest result date / Result
Reverse transcription-polymerase chain reaction (RT-PCR) / Veterinary
Research Institute (VRI), MOA / Birds / 2 / 3 Jul 2024 / 3 Jul 2024 /
Positive
Gene sequencing / Veterinary Research Institute (VRI), MOA / Birds / 2
/ 4 Jul 2024 / 4 Jul 2024 / Positive

New outbreaks [1]
Quantitative data summary
Outbreak location: Dounan Township, Yulin County, Chinese Taipei
Epidemiological unit: Farm
Start date: 29 Jun 2024
End date: -
Affected population description: Meat chickens
Detailed characterization: Clade 2.3.4.4b; Lineage: Fully Eurasian
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Birds (domestic) poultry / 27 629 / 550 / 550 / 27 079 / 0 / 0

New outbreaks [2]
Quantitative data summary
Outbreak location: Dounan Township, Yulin County, Chinese Taipei
Epidemiological unit: Farm
Start date: 29 Jun 2024
End date: -
Affected population description: Meat chickens
Detailed characterization: Clade 2.3.4.4b; Lineage: Fully Eurasian
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Birds (domestic) poultry / 25 511 / 8988 / 8988 / 16 523 / 0 / 0