Rabbit haemorrhagic disease,
United States of America
Information received on 18/12/2020 from Dr Mark Davidson, Associate Administrator, USDA-APHIS, United States Department of Agriculture, Washington, United States of America
Report type Immediate notification
Date of start of the event 10/12/2020
Date of confirmation of the event 16/12/2020
Report date 18/12/2020
Date submitted to OIE 18/12/2020
Reason for notification First occurrence of a listed disease
Manifestation of disease Sub-clinical infection
Causal agent Rabbit haemorrhagic disease virus
Serotype RHDV2
Nature of diagnosis Laboratory (advanced)
This event pertains to a defined zone within the country
Related reports Immediate notification (18/12/2020)
Follow-up report No. 1 (04/01/2021)
New outbreaks (1)
Outbreak 1 Albany County, Albany, Wyoming
Date of start of the outbreak 10/12/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Eastern Cottontail:Sylvilagus floridanus(Leporidae) 1 1 0 0
Affected population Wild Eastern cottontail rabbit (Sylvilagus floridanus)
Summary of outbreaks Total outbreaks: 1
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Eastern Cottontail:Sylvilagus floridanus(Leporidae) 1 1 0 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Eastern Cottontail:Sylvilagus floridanus(Leporidae) ** ** 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
Epidemiological comments Wyoming (WY)--RHDV2 confirmed in a wild Eastern cottontail rabbit (Sylvilagus floridanus) in Albany County, Wyoming. This is the first detection of RHDV2 in Wyoming and the first detection of RHDV2 in an Eastern cottontail rabbit in the United States. The Wyoming State Animal Health and Wildlife Officials and USDA, Animal Plant Health Inspection Service (APHIS) will continue to investigate reports of suspect sick or dead wild rabbits and feral or pet domestic rabbits for surveillance.
Control measures
Measures applied
  • Surveillance within containment and/or protection zone
  • 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
National Veterinary Services Laboratories (National laboratory) Eastern Cottontail reverse transcription - polymerase chain reaction (RT-PCR) 16/12/2020 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations