Infectious hypodermal and haematopoietic necrosis,
United Kingdom
Information received on 04/12/2020 from Dr Christine Middlemiss, Chief Veterinary Officer, DEFRA, Department for Environment,Food and Rural Affairs , London, United Kingdom
Summary
Report type Immediate notification
Date of start of the event 30/10/2020
Date of confirmation of the event 03/12/2020
Report date 04/12/2020
Date submitted to OIE 04/12/2020
Reason for notification Recurrence of a listed disease
Date of previous occurrence 12/2019
Manifestation of disease Clinical disease
Causal agent Infectious hypodermal and haematopoietic necrosis virus
Nature of diagnosis Laboratory (basic), Laboratory (advanced)
This event pertains to a defined zone within the country
Related reports Immediate notification (04/12/2020)
Follow-up report No. 1 (18/12/2020)
New outbreaks (1)
Outbreak 1 (IHHNV 20202-01) Linconlshire, England
Date of start of the outbreak 30/10/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Farm
Water type Salt water
Population type Farmed
Production system Closed
Affected animals
Species Morbidity Mortality Susceptible Cases Deaths Killed and disposed of Slaughtered
Whiteleg Shrimp (Litopenaeus vannamei) (kg) 0 (scale 0 to 5) 1 (scale 0 to 5)
Affected population The affected population consists of imported farmed shrimp. The animals are imported as SPF post larval shrimp and grown on for human consumption for the UK market only. Live animals are not exported from the facility, and with the exception of one movement to a bio-secure research facility, live animals do not leave the site. The shrimp are grown on in a fully enclosed recirculation facility, using artificial seawater made up on site and which is heated to 28 degrees centigrade. The site is located inland approx. 55 kilometres from coastal waters, and except for a contained irrigation reservoir, there are no other water courses within 1000 m of the facility. All effluent discharges into a soak away, and waste is disposed of in a bio-secure manner.
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Whiteleg Shrimp (Litopenaeus vannamei) (kg) **
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Whiteleg Shrimp (Litopenaeus vannamei) (kg) ** ** ** **
*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 With the exception of one movements of live animals to a fully enclosed, bio-secure facility, which took place prior to the start of the investigation there have been no movements of live animals from this facility. The site produces animals for human consumption only, the animals leave the site as raw product, on ice
Control measures
Measures applied
  • Movement control inside the country
  • Surveillance within infected and/or protection zone
  • Traceability
  • Quarantine
  • Vaccination permitted (if a vaccine exists)
  • No treatment of affected animals
Measures to be applied
  • Disinfection
Diagnostic test results
Laboratory name and type Species Test Test date Result
Centre for Environment, Fisheries and Aquaculture Science (National laboratory) Whiteleg Shrimp (Litopenaeus vannamei) gene sequencing 03/12/2020 Positive
Centre for Environment, Fisheries and Aquaculture Science (National laboratory) Whiteleg Shrimp (Litopenaeus vannamei) real-time PCR 03/12/2020 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations