Rabbit haemorrhagic disease,
United States of America
Information received on 05/05/2020 from Dr Mark Davidson, Associate Administrator, USDA-APHIS, United States Department of Agriculture, Washington, United States of America
Summary
Report type Follow-up report No. 13
Date of start of the event 08/07/2019
Date of confirmation of the event 17/07/2019
Report date 05/05/2020
Date submitted to OIE 05/05/2020
Date event resolved 03/07/2020
Reason for notification Recurrence of a listed disease
Date of previous occurrence 16/04/2019
Manifestation of disease Clinical disease
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 (19/07/2019)
Follow-up report No. 1 (08/08/2019)
Follow-up report No. 2 (16/08/2019)
Follow-up report No. 3 (30/08/2019)
Follow-up report No. 4 (03/12/2019)
Follow-up report No. 5 (07/01/2020)
Follow-up report No. 6 (06/03/2020)
Follow-up report No. 7 (13/03/2020)
Follow-up report No. 8 (27/03/2020)
Follow-up report No. 9 (06/04/2020)
Follow-up report No. 10 (13/04/2020)
Follow-up report No. 11 (20/04/2020)
Follow-up report No. 12 (27/04/2020)
Follow-up report No. 13 (05/05/2020)
Follow-up report No. 14 (13/05/2020)
Follow-up report No. 15 (19/05/2020)
Follow-up report No. 16 (27/05/2020)
Follow-up report No. 17 (01/06/2020)
Follow-up report No. 18 (09/06/2020)
Follow-up report No. 19 (17/06/2020)
Follow-up report No. 20 (23/06/2020)
Follow-up report No. 21 (29/06/2020)
Follow-up report No. 22 (02/07/2020)
New outbreaks (29)
Outbreak 1 Maricopa County, Maricopa, Arizona
Date of start of the outbreak 24/03/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 2 1 1 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 2 Curry County, Curry, New Mexico
Date of start of the outbreak 25/03/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 84 84 0 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 3 Cochise County, Cochise, Arizona
Date of start of the outbreak 01/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 30 22 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 4 Cochise County, Cochise, Arizona
Date of start of the outbreak 08/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 1 1 0 0
Affected population Wild Black-tailed jackrabbit (Lepus californicus)
Outbreak 5 Cochise County, Cochise, Arizona
Date of start of the outbreak 08/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Desert Cottontail:Sylvilagus audubonii(Leporidae) 1 1 0 0
Affected population Wild Desert cottontail rabbit (Sylvilagus audubonii)
Outbreak 6 Cochise County, Cochise, Arizona
Date of start of the outbreak 08/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 1 1 0 0
Affected population Wild Black-tailed jackrabbit (Lepus californicus)
Outbreak 7 Terrell County, Terrell, Texas
Date of start of the outbreak 14/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 40 40 0 0
Affected population Wild Black-tailed jackrabbits (Lepus californicus)
Outbreak 8 Otero County, Otero, New Mexico
Date of start of the outbreak 18/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 30 1 29 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 9 Santa Fe County, Santa Fe, New Mexico
Date of start of the outbreak 19/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Desert Cottontail:Sylvilagus audubonii(Leporidae) 20 20 0 0
Affected population Wild Desert cottontail rabbits (Sylvilagus audubonii)
Outbreak 10 El Paso County, El Paso, Texas
Date of start of the outbreak 20/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Desert Cottontail:Sylvilagus audubonii(Leporidae) 3 3 0 0
Affected population Wild Desert cottontail rabbits (Sylvilagus audubonii)
Outbreak 11 Pecos County, Pecos, Texas
Date of start of the outbreak 20/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Desert Cottontail:Sylvilagus audubonii(Leporidae) 2 2 0 0
Affected population Wild Desert cottontail rabbits (Sylvilagus audubonii)
Outbreak 12 Luna County, Luna, New Mexico
Date of start of the outbreak 21/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 7 7 7 0 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 13 Hamilton County, Hamilton, Texas
Date of start of the outbreak 23/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 18 2 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 14 Navajo County, Navajo, Arizona
Date of start of the outbreak 24/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 1 1 0 0
Affected population Wild Black-tailed jackrabbit (Lepus californicus)
Outbreak 15 Pima County, Pima, Arizona
Date of start of the outbreak 24/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Desert Cottontail:Sylvilagus audubonii(Leporidae) 1 1 0 0
Affected population Wild Desert cottontail rabbit (Sylvilagus audubonii)
Outbreak 16 Randall County, Randall, Texas
Date of start of the outbreak 24/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 1 1 0 0
Affected population Wild Black-tailed jackrabbit (Lepus californicus)
Outbreak 17 Pima County, Pima, Arizona
Date of start of the outbreak 24/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Antelope jackrabbit :Lepus alleni(Leporidae) 1 1 0 0
Affected population Wild Antelope Jackrabbit (Lepus alleni)
Outbreak 18 Apache County, Apache, Arizona
Date of start of the outbreak 24/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Mountain cottontail:Sylvilagus nuttallii(Leporidae) 1 1 0 0
Affected population Wild Mountain cottontail rabbit (Sylvilagus nutalli)
Outbreak 19 Valencia County, Valencia, New Mexico
Date of start of the outbreak 25/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 1 1 1 0 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 20 Clark County, Clark, Nevada
Date of start of the outbreak 27/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 5 3 0
Affected population Non-commercial pet rabbits (Oryctolagus cuniculus) housed at a rabbit rescue group foster residence
Outbreak 21 Bernalillo County, Bernalillo, New Mexico
Date of start of the outbreak 27/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 1 1 0 0
Affected population Wild Black-tailed jackrabbit (Lepus californicus)
Outbreak 22 Dona Ana County, Dona Ana, New Mexico
Date of start of the outbreak 28/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 3 2 1 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 23 Navajo County, Navajo, Arizona
Date of start of the outbreak 29/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 1 1 1 0 0
Affected population Non-commercial domestic rabbit (Oryctolagus cuniculus)
Outbreak 24 Apache County, Apache, Arizona
Date of start of the outbreak 29/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 1 1 1 0 0
Affected population Non-commercial domestic rabbit (Oryctolagus cuniculus)
Outbreak 25 Maricopa County, Maricopa, Arizona
Date of start of the outbreak 29/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 4 1 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 26 Coconino County, Coconino, Arizona
Date of start of the outbreak 29/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Mountain cottontail:Sylvilagus nuttallii(Leporidae) 1 1 0 0
Affected population Wild Mountain cottontail rabbit (Sylvilagus nutalli)
Outbreak 27 Apache County, Apache, Arizona
Date of start of the outbreak 30/04/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 1 1 1 0 0
Affected population Non-commercial domestic rabbit (Oryctolagus cuniculus)
Outbreak 28 Lampasas County, Lampasas, Texas
Date of start of the outbreak 01/05/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Backyard
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 79 26 43 0
Affected population Non-commercial domestic rabbits (Oryctolagus cuniculus)
Outbreak 29 Alamosa County, Alamosa, Colorado
Date of start of the outbreak 01/05/2020
Outbreak status Continuing (or date resolved not provided)
Epidemiological unit Not applicable
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Jackrabbit:Lepus(Leporidae) 1 1 0 0
Affected population Wild Jackrabbit (Lepus sp)
Summary of outbreaks Total outbreaks: 29
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Rabbits 266 11 ** 153 74 0
Black-tailed Jackrabbit:Lepus californicus(Leporidae) 45 45 0 0
Desert Cottontail:Sylvilagus audubonii(Leporidae) 27 27 0 0
Antelope jackrabbit :Lepus alleni(Leporidae) 1 1 0 0
Mountain cottontail:Sylvilagus nuttallii(Leporidae) 2 2 0 0
Jackrabbit:Lepus(Leporidae) 1 1 0 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Rabbits ** 57.52% ** **
Black-tailed Jackrabbit:Lepus californicus(Leporidae) ** ** 100.00% **
Desert Cottontail:Sylvilagus audubonii(Leporidae) ** ** 100.00% **
Antelope jackrabbit :Lepus alleni(Leporidae) ** ** 100.00% **
Mountain cottontail:Sylvilagus nuttallii(Leporidae) ** ** 100.00% **
Jackrabbit:Lepus(Leporidae) ** ** 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 Update May 5, 2020: Nevada (NV)--RHDV2 confirmed in domestic rabbits (Oryctolagus cuniculus) from one non-commercial premises in Clark County, NV on 30 Apr 2020. This is the first detection of RHDV2 in Nevada. The premises fosters rescued rabbits and received a rescue rabbit from an animal shelter on 24 Apr 20 which subsequently died. The affected premises has been quarantined. Nevada State Animal Health Officials and the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Services (APHIS) have begun an epidemiological investigation into the outbreak. Colorado (CO)--RHDV2 confirmed in a wild Jackrabbit (Lepus sp.) from Alamosa County. Colorado State Animal Health Officials and USDA, APHIS continue an epidemiological investigation into the current outbreaks. Arizona (AZ)--RHDV2 confirmed in domestic rabbits (Oryctolagus cuniculus) on six additional non-commercial premises. Total positive premises in Arizona is 13. All affected premises have been quarantined and depopulation has been completed on six of the affected premises. Disposal activities are ongoing. There have also been eight new wild rabbit detections of RHDV2, including confirmation in Mountain cottontail rabbits (Sylvilagus nutalli) and an Antelope Jackrabbit (Lepus alleni). These are the first detections in the named wild species of RHDV2 in the United States. Arizona State Animal Health Officials and the USDA, APHIS continue an epidemiological investigation into the current outbreaks. Texas (TX)--RHDV2 confirmed in domestic rabbits (Oryctolagus cuniculus) on two additional non-commercial premises in Hamilton and Lampasas Counties. Total positive premises in Texas is five. There have been four new wild rabbit detections of RHDV2 in Desert cottontail rabbits (Sylvilagus audubonii) and Black-tailed jackrabbits (Lepus californicus) from several counties within the state. Texas State Animal Health Officials and the USDA, APHIS continue an epidemiological investigation into the current outbreaks. New Mexico (NM)--RHDV2 confirmed in domestic rabbits (Oryctolagus cuniculus) from five additional non-commercial premises. Total positive premises in New Mexico is 26. All affected premises have been quarantined and depopulation has been completed on 22 of the affected premises. Disposal activities are ongoing. Three of the affected premises completed cleaning and disinfection activities and now begin a 90-day fallow period. In addition, there have been wild rabbit detections in Desert cottontail rabbits (Sylvilagus audubonii) and a Black-tailed jackrabbit (Lepus californicus). New Mexico State Animal Health Officials and the USDA, APHIS continue their epidemiological investigation into the current outbreaks. Washington (WA)--State officials have extended the quarantine period at the affected animal sanctuary in Clallam County due to continued rabbit deaths. General clinical signs seen in confirmed cases from all the affected states include lethargy, seizures, and sudden death. Full genome sequencing and analysis was completed on RHDV2 isolates detected in the United States from 2018 through 2020, including from the ongoing outbreak in the southwestern United States. Phylogenetic analysis indicates isolates cluster by geographical region. Recent 2020 isolates from CO, AZ, NM, and TX formed a single genetic cluster suggesting the outbreak of RHDV2 in these states was caused by introduction of a single genetic isolate into the region; this virus is responsible for RHDV2 in both wild rabbits and domestic rabbits. Virus circulating in the southwest United States is distinct from RHDV2 isolates collected from domestic rabbits in New York, Washington State, and Ohio as well as British Columbia, Canada.
Control measures
Measures applied
  • Surveillance within containment and/or protection zone
  • Traceability
  • Quarantine
  • Disinfection
  • 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
National Veterinary Services Laboratories (National laboratory) Antelope jackrabbit reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
National Veterinary Services Laboratories (National laboratory) Black-tailed Jackrabbit reverse transcription - polymerase chain reaction (RT-PCR) 29/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Black-tailed Jackrabbit reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
National Veterinary Services Laboratories (National laboratory) Desert Cottontail reverse transcription - polymerase chain reaction (RT-PCR) 27/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Desert Cottontail reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
National Veterinary Services Laboratories (National laboratory) Jackrabbit reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
National Veterinary Services Laboratories (National laboratory) Mountain cottontail reverse transcription - polymerase chain reaction (RT-PCR) 29/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Mountain cottontail reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
National Veterinary Services Laboratories (National laboratory) Rabbits antigen (Ag) detection ELISA 30/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Rabbits reverse transcription - polymerase chain reaction (RT-PCR) 27/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Rabbits reverse transcription - polymerase chain reaction (RT-PCR) 29/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Rabbits reverse transcription - polymerase chain reaction (RT-PCR) 30/04/2020 Positive
National Veterinary Services Laboratories (National laboratory) Rabbits reverse transcription - polymerase chain reaction (RT-PCR) 01/05/2020 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations