Should the 40-year-old practice of releasing virulent myxoma virus to control rabbits (Oryctolagus cuniculus) be continued?

2006 ◽  
Vol 33 (7) ◽  
pp. 549 ◽  
Author(s):  
D. Berman ◽  
P. J. Kerr ◽  
R. Stagg ◽  
B. H. van Leeuwen ◽  
T. Gonzalez
Keyword(s):  
Virulent Strain ◽  
Clinical Signs ◽  
Laboratory Strain ◽  
Myxoma Virus ◽  
South West ◽  
Rabbit Haemorrhagic Disease ◽  
Virulent Virus ◽  
Original Laboratory ◽  
The 1960S ◽  
Haemorrhagic Disease

Release of virulent myxoma virus has been a key component of rabbit-control operations in Queensland, Australia, since the 1960s but its use rests on anecdotal reports. During a routine operation to release virulent myxoma virus we found no evidence to support the continued regular use of the technique in south-west Queensland. Radio-tagged rabbits inoculated with virulent myxoma virus contracted the disease but failed to pass enough virus to other rabbits to spread the disease. Rabbits with clinical signs of myxomatosis that were shot were infected with field strain derived from the original laboratory strain released in 1950 rather than the virulent strain that has been released annually. There was no change in rabbit survival or abundance caused by the release. Nevertheless, the release of virulent virus may be useful against isolated pockets of rabbits mainly because field strains are less likely to be present. Such pockets are more common now that rabbit haemorrhagic disease virus is established in Queensland.

scholarly journals A Potential Atypical Case of Rabbit Haemorrhagic Disease in a Dwarf Rabbit

Animals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 40
Author(s):  
Fábio A. Abade dos Santos ◽  
Carolina Magro ◽  
Carina L. Carvalho ◽  
Pedro Ruivo ◽  
Margarida D. Duarte ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Myxoma Virus ◽  
European Rabbit ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Structural Genes ◽  
Bivalent Vaccine ◽  
Rabbit Haemorrhagic Disease ◽  
Cross Immunity ◽  
Domestic Rabbits ◽  
Haemorrhagic Disease

Rabbit haemorrhagic disease (RHD) is a highly contagious infectious disease of European wild and domestic rabbits. Rabbit haemorrhagic disease virus (RHDV, GI.1) emerged in 1986 in Europe, rapidly spreading all over the world. Several genotypes of RHDV have been recognised over time, but in 2010, a new virus (RHDV2/RHDVb, GI.2) emerged and progressively replaced the previous RHDV strains, due to the lack of cross-immunity conferred between RHDV and RHDV2. RHDV2 has a high mutation rate, similarly to the other calivirus and recombines with strains of RHDV and non-pathogenic calicivirus (GI.4), ensuring the continuous emergence of new field strains. Although this poses a threat to the already endangered European rabbit species, the available vaccines against RHDV2 and the compliance of biosafety measures seem to be controlling the infection in the rabbit industry Pet rabbits, especially when kept indoor, are considered at lower risk of infections, although RHDV2 and myxoma virus (MYXV) constitute a permanent threat due to transmission via insects. Vaccination against these viruses is therefore recommended every 6 months (myxomatosis) or annually (rabbit haemorrhagic disease). The combined immunization for myxomatosis and RHDV through a commercially available bivalent vaccine with RHDV antigen has been extensively used (Nobivac® Myxo-RHD, MSD, Kenilworth, NJ, USA). This vaccine however does not confer proper protection against the RHDV2, thus the need for a rabbit clinical vaccination protocol update. Here we report a clinical case of hepatitis and alteration of coagulation in a pet rabbit that had been vaccinated with the commercially available bivalent vaccine against RHDV and tested positive to RHDV2 after death. The animal developed a prolonged and atypical disease, compatible with RHD. The virus was identified to be an RHDV2 recombinant strain, with the structural backbone of RHDV2 (GI.2) and the non-structural genes of non-pathogenic-A1 strains (RCV-A1, GI.4). Although confirmation of the etiological agent was only made after death, the clinical signs and analytic data were very suggestive of RHD.

scholarly journals Molecular epidemiology of Rabbit haemorrhagic disease virus

2002 ◽  
Vol 83 (10) ◽  
pp. 2461-2467 ◽  
Author(s):  
S. R. Moss ◽  
S. L. Turner ◽  
R. C. Trout ◽  
P. J. White ◽  
P. J. Hudson ◽  
...  
Keyword(s):  
Disease Virus ◽  
Nucleotide Sequencing ◽  
Molecular Evidence ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Rabbit Haemorrhagic Disease ◽  
Molecular Phylogenetic ◽  
Virulent Virus ◽  
Rabbit Bone ◽  
European Rabbits ◽  
Haemorrhagic Disease

Millions of domestic and wild European rabbits (Oryctolagus cuniculus) have died in Europe, Asia, Australia and New Zealand during the past 17 years following infection by Rabbit haemorrhagic disease virus (RHDV). This highly contagious and deadly disease was first identified in China in 1984. Epidemics of RHDV then radiated across Europe until the virus apparently appeared in Britain in 1992. However, this concept of radiation of a new and virulent virus from China is not entirely consistent with serological and molecular evidence. This study shows, using RT–PCR and nucleotide sequencing of RNA obtained from the serum of healthy rabbits stored at 4 °C for nearly 50 years, that, contrary to previous opinions, RHDV circulated as an apparently avirulent virus throughout Britain more than 50 years ago and more than 30 years before the disease itself was identified. Based on molecular phylogenetic analysis of British and European RHDV sequences, it is concluded that RHDV has almost certainly circulated harmlessly in Britain and Europe for centuries rather than decades. Moreover, analysis of partial capsid sequences did not reveal significant differences between RHDV isolates that came from either healthy rabbits or animals that had died with typical haemorrhagic disease. The high stability of RHDV RNA is also demonstrated by showing that it can be amplified and sequenced from rabbit bone marrow samples collected at least 7 weeks after the animal has died.

scholarly journals Novel Trivalent Vectored Vaccine for Control of Myxomatosis and Disease Caused by Classical and a New Genotype of Rabbit Haemorrhagic Disease Virus

Vaccines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 441 ◽  
Author(s):  
Sylvia Reemers ◽  
Leon Peeters ◽  
Joyce van Schijndel ◽  
Beth Bruton ◽  
David Sutton ◽  
...  
Keyword(s):  
Disease Virus ◽  
Myxoma Virus ◽  
European Rabbit ◽  
Viral Diseases ◽  
Serological Response ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Rabbit Haemorrhagic Disease ◽  
New Genotype ◽  
Vectored Vaccine ◽  
Haemorrhagic Disease

Myxoma virus (MV) and rabbit haemorrhagic disease virus (RHDV) are the major causes of lethal viral diseases in the European rabbit. In 2010, a new RHDV genotype (RHDV2) emerged in the field that had limited cross-protection with the classical RHDV (RHDV1). For optimal protection of rabbits and preventing spread of disease, a vaccine providing protection against all three key viruses would be ideal. Therefore, a novel trivalent myxoma vectored RHDV vaccine (Nobivac Myxo-RHD PLUS) was developed similar to the existing bivalent myxoma vectored RHDV vaccine Nobivac Myxo-RHD. The new vaccine contains the Myxo-RHDV1 strain already included in Nobivac Myxo-RHD and a similarly produced Myxo-RHDV2 strain. This paper describes several key safety and efficacy studies conducted for European licensing purposes. Nobivac Myxo-RHD PLUS showed to be safe for use in rabbits from five weeks of age onwards, including pregnant rabbits, and did not spread from vaccinated rabbits to in-contact controls. Furthermore, protection to RHDV1 and RHDV2 was demonstrated by challenge, while the serological response to MV was similar to that after vaccination with Nobivac Myxo-RHD. Therefore, routine vaccination with Nobivac Myxo-RHD PLUS can prevent the kept rabbit population from these major viral diseases.

Potential use of myxoma virus and rabbit haemorrhagic disease virus to control feral rabbits in the Kerguelen Archipelago

2004 ◽  
Vol 31 (4) ◽  
pp. 415 ◽  
Author(s):  
B. D. Cooke ◽  
J.-L. Chapuis ◽  
V. Magnet ◽  
A. Lucas ◽  
J. Kovaliski
Keyword(s):  
Disease Virus ◽  
Disease Transmission ◽  
Biological Control Agent ◽  
Myxoma Virus ◽  
European Rabbit ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Rabbit Haemorrhagic Disease ◽  
Haemorrhagic Disease ◽  
Low Prevalence ◽  
Kerguelen Archipelago

Rabbits have caused enormous damage to the vegetation on seven islands in the sub-Antarctic Kerguelen archipelago, including the main island, Grande Terre. Rabbit sera collected during 2001–02 were tested for antibodies against myxoma virus and rabbit haemorrhagic disease virus with a view to considering the wider use of these viruses to control rabbits. The results confirmed work done 15–20 years earlier that suggested that myxoma virus has not spread across all parts of Grande Terre and occurs at low prevalence among rabbits. By contrast, on Ile du Cimetière, where European rabbit fleas were introduced in 1987–88, the prevalence of myxoma antibodies is high and the rabbit population is relatively low, supporting the idea that the fleas are effective vectors of myxoma virus. Consequently, there should be benefits in releasing fleas on Grand Terre to enhance disease transmission. Reactivity of some rabbit sera in RHD-specific ELISAs suggested that a virus similar to RHDV may be present at low prevalence on Grande Terre but most rabbits are likely to be susceptible and this virus could be considered for use as a future biological control agent.

scholarly journals Humoral immune response to different routes of myxomatosis vaccine application

2018 ◽  
Vol 26 (2) ◽  
pp. 149
Author(s):  
I. Manev ◽  
K. Genova ◽  
A. Lavazza ◽  
L. Capucci
Keyword(s):  
Clinical Signs ◽  
Humoral Response ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Response ◽  
Humoral Immune ◽  
Routes Of Administration ◽  
Monovalent Vaccine ◽  
Rabbit Haemorrhagic Disease ◽  
Different Types ◽  
Haemorrhagic Disease

The aim of our study was to monitor the dynamics of the serological response to different application routes of live attenuated myxomatosis vaccine. The study included 42 Californian breed rabbits, aged 3 mo, of both sexes. They were separated into 7 groups: 6 experimental and 1 control. All experimental groups were vaccinated on day 0 with a single dose of myxomatosis vaccine (min 10<sup>3.3</sup> tissue culture infective dose 50 [TCID<sub>50</sub>], max 10<sup>5.8</sup> TCID<sub>50</sub>). Three of the groups were injected with monovalent attenuated myxomatosis vaccine using different types of application: intradermal (i.d.), intramuscular (i.m.) and subcutaneous (s.c.). The other 3 groups were injected with bivalent attenuated vaccine against myxomatosis and rabbit haemorrhagic disease; again the routes of administration were i.d., i.m. and s.c.. There were no clinical signs or serious side effects after vaccination. The serological response was evaluated on days 7, 15 and 30 with a monoclonal antibody based-competition enzyme-linked immunosorbent assay (cELISA). More rapid and potent humoral response was detected in groups with i.d. inoculation in comparison to i.m. and s.c. routes. Vaccination with monovalent vaccine against myxomatosis induced higher antibody titre in comparison to bivalent vaccine. Our study showed that the vaccine application route and the type of vaccine used influence the speed and intensity of antibody response.

Rabbit Haemorrhagic Disease Virus: serological evidence of a non-virulent RHDV-like virus in south-western Australia

2004 ◽  
Vol 31 (6) ◽  
pp. 605 ◽  
Author(s):  
John S. Bruce ◽  
Laurie E. Twigg
Keyword(s):  
Disease Virus ◽  
Western Australia ◽  
Biological Control Agent ◽  
Clinical Signs ◽  
Wild Rabbit ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Serological Evidence ◽  
Rabbit Haemorrhagic Disease ◽  
European Rabbits ◽  
Haemorrhagic Disease

Although several different cELISAs have been used to assess the exposure of European rabbits to rabbit haemorrhagic disease (RHD), the interpretation of the results of such assays is not always straight-forward. Here we report on such difficulties, and on the likely presence of a non-virulent rabbit haemorrhagic disease virus–like virus (nvRHDV-LV) in south-western Australia. Analysis of sera collected from European rabbits at Kojaneerup (near Albany) in Western Australia provided the first serological evidence of the likely presence of a nvRHDV-LV in wild rabbit populations outside the east coast of Australia and New Zealand, before the deliberate introduction of RHDV as biological control agent in both countries. Six out of 30 rabbits (20%) sampled 1–2 months before the known arrival of RHDV at Kojaneerup were seropositive to RHD on the basis of their IgG isoELISAs. However, none of these positive samples were positive for the RHDV antibody cELISA (1 : 10), indicating likely exposure to nvRHDV-LV. Subsequent serological analysis of 986 rabbits sampled between September 1996 and August 1999 at Kojaneerup indicated that nvRHDV-LV persisted in these rabbits following the natural arrival of RHDV in September 1996. At least 10–34% of rabbits appeared to have been exposed to nvRHDV-LV during the 3-year study. The presence of nvRHDV-LV seemed to offer only limited protection to rabbits from RHDV during the initial epizootic; however, persistence of nvRHDV-LV may have mitigated further RHDV activity after this epizootic. Fewer than 1% of rabbits (9 of 986) showed evidence of RHDV-challenge during the 30 months following the initial RHDV epizootic. Furthermore, except for the epizootic in September 1996, no clinical signs of the disease were apparent in the population until RHDV was deliberately reintroduced in April 1999. Mortality of rabbits exposed to RHDV at this time appeared to be correlated with their IgG isoELISA titre.

Previous exposure to myxoma virus reduces survival of European rabbits during outbreaks of rabbit haemorrhagic disease

2018 ◽  
Vol 55 (6) ◽  
pp. 2954-2962 ◽  
Author(s):  
Louise K. Barnett ◽  
Thomas A. A. Prowse ◽  
David E. Peacock ◽  
Gregory J. Mutze ◽  
Ron G. Sinclair ◽  
...  
Keyword(s):  
Myxoma Virus ◽  
Previous Exposure ◽  
Rabbit Haemorrhagic Disease ◽  
European Rabbits ◽  
Haemorrhagic Disease

Myxoma virus and rabbit haemorrhagic disease virus 2 coinfection in a European wild rabbit (Oryctolagus cuniculus algirus), Portugal

2020 ◽  
Vol 8 (1) ◽  
pp. e001002 ◽  
Author(s):  
Carina Luisa Carvalho ◽  
Fábio Alexandre Abade dos Santos ◽  
Teresa Fagulha ◽  
Paulo Carvalho ◽  
Paula Mendonça ◽  
...  
Keyword(s):  
Disease Virus ◽  
Oryctolagus Cuniculus ◽  
Rare Event ◽  
Myxoma Virus ◽  
European Rabbit ◽  
Wild Rabbit ◽  
Rabbit Haemorrhagic Disease Virus ◽  
Sample Collection ◽  
Rabbit Haemorrhagic Disease ◽  
Haemorrhagic Disease

Myxoma virus (MYXV) and rabbit haemorrhagic disease virus 2 (RHDV2) are two major pathogens that affect the European rabbit (Oryctolagus cuniculus). Between August 2017 and August 2019, 1166 wild rabbits (971 legally hunted and 195 found dead) were tested by PCR-based methods for MYXV and RHDV2 within the scope of an ongoing surveillance programme on wild leporids in Portugal. Despite never having been reported before and being considered a rare event, coinfection by RHDV2 and MYXV was detected in one juvenile wild rabbit found dead in the Évora district located in Alentejo. The relative frequency of coinfection in the group of diseased rabbits (found dead in the field) was 0.52 per cent (1/195). The positivity percentage of each single virus was much higher, namely, 14.36 per cent (28/195) for MYXV and 55.38 per cent (108/195) for RHDV2, within the 2 years of sample collection considered.

scholarly journals Limited overlap in RNA virome composition among rabbits and their ectoparasites reveals barriers to virus transmission

2019 ◽  
Author(s):  
Jackie E. Mahar ◽  
Mang Shi ◽  
Robyn N. Hall ◽  
Tanja Strive ◽  
Edward C. Holmes
Keyword(s):  
Rna Virus ◽  
Virus Transmission ◽  
Myxoma Virus ◽  
Gut Contents ◽  
Mechanical Transmission ◽  
The Novel ◽  
Caecal Content ◽  
Rabbit Haemorrhagic Disease ◽  
Haemorrhagic Disease

AbstractEctoparasites play an important role in virus transmission among vertebrates. However, little is known about the extent and composition of viruses that pass between invertebrates and vertebrates. In Australia, flies and fleas support the mechanical transmission of viral biological controls against wild rabbits - rabbit haemorrhagic disease virus (RHDV) and myxoma virus. We compared virome structure and composition in rabbits and these associated ectoparasites, sequencing total RNA from multiple tissues and gut contents of wild rabbits, fleas collected from these rabbits, and flies trapped sympatrically. Meta-transcriptomic analyses identified 50 novel viruses from multiple RNA virus families. Rabbits and their ectoparasites were characterised by markedly different viromes: although viral contigs from six virus families/groups were found in both rabbits and ectoparasites, none were vertebrate-associated. A novel calicivirus and picornavirus detected in rabbit caecal content were vertebrate-specific: the newly detected calicivirus was distinct from known rabbit caliciviruses, while the novel picornavirus clustered with the Sapeloviruses. Several Picobirnaviridae were also identified, falling in diverse phylogenetic positions suggestive of an association with co-infecting bacteria. The remaining viruses found in rabbits, and all those from ectoparasites, were likely associated with invertebrates, plants and co-infecting endosymbionts. While no full genomes of vertebrate-associated viruses were detected in ectoparasites, suggestive of major barriers to biological transmission with active replication, small numbers of reads from rabbit astrovirus, RHDV and other lagoviruses were present in flies. This supports the role of flies in the mechanical transmission of RHDV and implies that they may assist the spread of astroviruses.

Sign in / Sign up

Export Citation Format

Share Document