Published Date: 2022-11-22 05:27:41 EST 
Subject: PRO/AH> Rabbit hemorrhagic disease - South Africa: (WC,NC) wild, RHDV, 1st rep, WOAH 
Archive Number: 20221122.8706840

A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases

In this post:
[1] WOAH report
[2] Press release

[1] WOAH report
Date: Fri 18 Nov 2022
Source: WOAH-WAHIS (World Organisation for Animal Health-World Animal Health Information System) 2022 [edited]

South Africa - rabbit hemorrhagic disease
Report type: immediate notification
Started: 31 Aug 2022
Confirmed: 14 Nov 2022
Reported: 18 Nov 2022
Reason for notification: 1st occurrence in the country
Causal agent: rabbit hemorrhagic disease virus
Genotype: pending
Nature of diagnosis: necropsy, clinical, laboratory
This event pertains to the whole country.

Outbreak location: Karoo Hoogland, Namakwa, Northern Cape
Started: 31 Aug 2022
Epidemiological unit: other
Total animals affected:
Species / Susceptible / Cases / Deaths / Killed and disposed of / Slaughtered or killed for commercial use / Vaccinated
Leporidae (unidentified) (wild) / - / 100 / 100 / 0 / 0 / 0

Source of the outbreak(s) or origin of infection: unknown or inconclusive

Applied control measures at event level, domestic animals: quarantine

Diagnostic test results
Laboratory name and type: Onderstepoort Veterinary Institute (OVI)
Species / Test / Outbreaks / Last result date / Result
Leporidae (unidentified) / reverse transcription-polymerase chain reaction (RT-PCR) / 1 / 14 Nov 2022 / positive

[The location of the outbreak can be seen on the interactive map included in the WOAH report at the source URL above.

Please note that any discrepancies in event start, confirmation, and other dates in ProMED posts and the WOAH corresponding reports are the result of a technical problem already being addressed by WOAH. - Mod.CRD]

communicated by:

[2] Press release
Date: Fri 18 Nov 2022
Source: South African Government News Agency [edited]

The Department of Agriculture, Land Reform and Rural Development (DALRRD) has confirmed the outbreak of rabbit hemorrhagic disease (RHD) in the Western Cape and Northern Cape provinces. The department said it has received reports of die-offs of wild rabbits and hares from the Karoo areas in the Western and Northern Cape.

"State veterinary services, private veterinarians, and the Department of Forestry, Fisheries and the Environment were involved in field investigations. Post-mortems were performed and samples collected to confirm the cause of the deaths. Diagnostic tests were performed at the Onderstepoort Veterinary Research Laboratory, and the cause was confirmed as rabbit haemorrhagic disease," the department said in a statement.

RHD is a disease caused by a virus, calicivirus, resulting in a high number of deaths in rabbits and hares, and the sudden death of animals due to bleeding in the organs including the liver, kidney, and spleen.

The department said this is the 1st detection of the disease in South Africa, and at this stage it is still unclear how the disease could have entered the country, since the importation of rabbits and hares is not allowed. The department said investigations are under way to determine whether illegal importation could be the source.

"Control of RHD in rabbitries relies mainly on vaccination, but the vaccine is not available in South Africa. This increases the importance of biosecurity measures in rabbitries and anywhere where rabbits or hares are kept. Biosecurity measures are difficult to implement in wild populations. The occurrence of RHD in the Karoo is therefore of great concern, as our indigenous Red Rock rabbit, endangered Riverine rabbit and hare species are highly susceptible to this disease," the department said.

The department warned that carcasses of RHD-infected rabbits might be a major source for viral spreading, since the virus seems to be highly resistant and stable, even when exposed to harsh environmental conditions. Rabbit owners have been advised to ensure that their rabbits are secured and must prevent any contact with other rabbits or hares, either directly or indirectly through people or equipment. Members of the public have also been encouraged to report any dead or dying rabbits or hares to the nearest state veterinarian for investigation.

communicated by:

["Rabbit hemorrhagic disease is a serious and extremely contagious viral disease of the European rabbit (_Oryctolagus cuniculus_). Morbidity and mortality rates are high in unvaccinated animals; on some farms, most or all naive rabbits may die. ... The disease caused dramatic declines in some wild rabbit populations, particularly when it was first introduced...

"Classical RHDV and/or RHDVa are endemic in some areas with wild European rabbits, including Australia, New Zealand, some islands (e.g., Cuba), parts of Asia and Africa, and most of Europe. Susceptible wild lagomorphs do not exist in most of North America, though feral European rabbits do occur in a few locations. RHDV was found in both domestic and wild rabbits in South America (Uruguay) in 2005, but there are no reports of its occurrence since that time, and Uruguay reported itself to be free of rabbit hemorrhagic disease as of 2012.

"As of 2020, RHDV2 has become established in wild lagomorphs in a number of European countries, Australia, and parts of Africa. In some locations, RHDV2 has largely replaced classical RHDV or RHDVa. Outbreaks have also been reported in New Zealand and some countries in the Middle East, Asia, and North America, but whether the virus will persist in some of these locations is not yet certain. In North America, this virus was found in both domestic and feral rabbits." ( - Mod.CRD