Summary
Report type: immediate notification
Started: 13 Nov 2022
Confirmed: 17 Nov 2022
Reported: 18 Nov 2022
Reason for notification: recurrence
Last occurrence: 29 Apr 2022
Causal agent: highly pathogenic avian influenza virus
Serotype: H5N1
Nature of diagnosis: clinical, laboratory
This event pertains to the whole country.

Outbreak: Seuzach, Winterthur, Zurich
Started: 13 Nov 2022
Epidemiological unit: other
Total animals affected:
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Grey heron (wild) / - / 1 / 1 / 0 / 0 / 0
Birds (domestic) / 100 / 1 / 1 / 0 / 0 / 0

Affected population: the 2 birds have been found in a parcel of land
in the municipality of Seuzach, where around 100 birds of several
species are kept in an aviary and in a natural pond. A wild grey heron
(_Ardea cinerea_) was found dead on 14 Nov 2022. Samples were sent to
the National Reference Center for Poultry and Rabbit Diseases (NRGK,
Zurich, Switzerland), where they tested positive for avian influenza
of the subtype H5N1 in RT-qPCR on Datum. Confirmation and sequencing
analyses were carried out at the Institute of Virology and lmmunology
(IVI, Mittelh鋟sern, Switzerland) where highly pathogenic avian
influenza was confirmed on Datum. A peacock (_Pavo cristatus_) was
found dead on 16 Nov 2022. Samples were sent to the National Reference
Center for Poultry and Rabbit Diseases (NRGK, Zurich, Switzerland),
where they tested positive for avian influenza of the subtype H5N1 in
RT-qPCR on Datum. Confirmation and sequencing analyses were carried
out at the Institute of Virology and lmmunology (IVI, Mittelh鋟sern,
Switzerland) where highly pathogenic avian influenza was confirmed on
18 Nov 2022. Epidemiological investigations are ongoing. There have
been no movements of animals or products of animal origin from the
establishment. However, the pond is accessible for wild birds. The
establishment has been put under movement restriction. Killing and
sampling of remaining birds is under preparation. Further measures
such as establishing a protection and a surveillance zone are foreseen
for the next days.

Epidemiology
Source of the outbreak(s) or origin of infection: contact with wild
species

Control measures applied in domestic animals: zoning; surveillance
within the restricted zone; disinfection; screening; movement
control.
Control measures applied in domestic animals: zoning; screening;
control of wildlife reservoirs.

Diagnostic test results
Laboratory name and type / Species / Test / Last result date / Result
National Reference Centre for Diseases of Poultry and Rabbits (NRGK),
Vetsuisse Faculty Zurich, University of Zurich / birds, grey heron /
reverse transcription-polymerase chain reaction (RT-PCR) / 17 Nov 2022
/ positive