Information received on 23/12/2020 from Dr Christianne Bruschke, Chief Veterinary Officer , Agriculture, Nature and Food Quality, Ministry of Agriculture, Nature and Food Quality, The Hague, Netherlands
Summary
Report type
Follow-up report No. 1
Date of start of the event
16/10/2020
Date of confirmation of the event
27/10/2020
Report date
23/12/2020
Date submitted to OIE
23/12/2020
Reason for notification
New strain of a listed disease in the country
Causal agent
Highly pathogenic influenza A virus
Serotype
H5N1
Nature of diagnosis
Clinical, Laboratory (advanced)
This event pertains to
a defined zone within the country
Related reports
Immediate notification (07/11/2020)
Follow-up report No. 1 (23/12/2020)
New outbreaks (1)

Outbreak 1
Groet, Noord-Holland
Date of start of the outbreak
09/11/2020
Outbreak status
Continuing (or date resolved not provided)
Epidemiological unit
Other
Affected animals
Species
Susceptible
Cases
Deaths
Killed and disposed of
Slaughtered
Mute Swan:Cygnus olor(Anatidae)

1
1
0
0
Affected population
On the 9th of November, one mute swan (Cygnus Olor) was found dead in a wetland area. On the 23rd of November, the National Reference Laboratory confirmed highly pathogenic avian influenza H5N1 in the sample from the mute swan (Cygnus Olor).
Summary of outbreaks
Total outbreaks: 1
Total animals affected
Species
Susceptible
Cases
Deaths
Killed and disposed of
Slaughtered
Mute Swan:Cygnus olor(Anatidae)

1
1
0
0
Outbreak statistics
Species
Apparent morbidity rate
Apparent mortality rate
Apparent case fatality rate
Proportion susceptible animals lost*
Mute Swan:Cygnus olor(Anatidae)
**
**
100.00%
**
*Removed from the susceptible population through death, destruction and/or slaughter
**Not calculated because of missing information
Epidemiology
Source of the outbreak(s) or origin of infection
Unknown or inconclusive
Epidemiological comments
The haemagglutinin (HA) is nearly identical to the HA of the H5N8 wild bird isolates reported in 2020. The other genes are of LPAI origin.

Control measures
Measures applied
Vaccination prohibited
No treatment of affected animals
Measures to be applied
No other measures
Diagnostic test results
Laboratory name and type
Species
Test
Test date
Result
Wageningen Bioveterinary Research Lelystad (National laboratory)
Mute Swan
polymerase chain reaction (PCR)
23/11/2020
Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.