Crayfish plague (Aphanomyces astaci),
United Kingdom
Information received on 15/10/2018 from Dr Christine Middlemiss, Chief Veterinary Officer, DEFRA, Department for Environment,Food and Rural Affairs , London, United Kingdom
Report type Immediate notification
Date of start of the event 31/08/2018
Date of confirmation of the event 14/09/2018
Report date 15/10/2018
Date submitted to OIE 15/10/2018
Date event resolved 31/08/2018
Reason for notification Recurrence of a listed disease
Date of previous occurrence 06/2018
Manifestation of disease Clinical disease
Causal agent Aphanomyces astaci
Nature of diagnosis Clinical
This event pertains to a defined zone within the country
Related reports Immediate notification (15/10/2018)
Follow-up report No. 1 (01/02/2019)
New outbreaks (1)
Outbreak 1 Headwater of the River Blackwater, near Aughentaine, Blackwater, Tyrone , Northern Ireland
Date of start of the outbreak 31/08/2018
Outbreak status Resolved (31/08/2018)
Epidemiological unit River system
Water type Fresh water
Population type Wild
Production system Open
Affected animals
Species Morbidity Mortality Susceptible Cases Deaths Killed and disposed of Slaughtered
White clawed crayfish (Austropotamobius pallipes) 100 % 100 % 20 20 0 0
Affected population Twenty dead white-clawed crayfish, which were found during routine field surveys, have subsequently tested positive for crayfish plague. The location where the crayfish were found was at the headwater of the River Blackwater, near Aughentaine. This section of the river was enhanced for salmon habitat during the 1990ís and 2000ís. Surveillance is on-going. No further reports to date.
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
White clawed crayfish (Austropotamobius pallipes) 20 20 0 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
White clawed crayfish (Austropotamobius pallipes) ** ** 100.00% **
*Removed from the susceptible population through death, destruction and/or slaughter
**Not calculated because of missing information
Source of the outbreak(s) or origin of infection
  • Unknown or inconclusive
Control measures
Measures applied
  • Vaccination permitted (if a vaccine exists)
  • No treatment of affected animals
Measures to be applied
  • No other measures
Diagnostic test results
Laboratory name and type Species Test Test date Result
Marine Institute (Regional Reference Laboratory) White clawed crayfish (Austropotamobius pallipes) polymerase chain reaction (PCR) 14/09/2018 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations