RHDV2 overcoming RHDV immunity in wild rabbits (<i>Oryctolagus cuniculus</i>) in Australia

Peacock, David; Kovaliski, John; Sinclair, Ron; Mutze, Greg; Iannella, Amy; Capucci, Lorenzo

doi:10.1136/vr.104135

Cited by 38 publications

(47 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the limited information of the vaccination status of domestic rabbits in this study and, perhaps more importantly, the lack of information about numbers of vaccinated rabbits that have survived GI.2 infection, it is not possible to estimate the effectiveness of the GI.1 vaccine in preventing disease caused by GI.2. However, the detection of GI.2 in 15 vaccinated domestic rabbits supports previous work demonstrating that cross-protection between GI.1 and GI.2 is at best incomplete, and a vaccine covering GI.2 is urgently needed to protect farmed and pet rabbits in Australia (20).…”

supporting

confidence: 75%

“…Based on these data, the GI.2 infection rate was higher than would have been expected with GI.1 alone, and GI.1 detections were well below what would be expected normally. This replacement may have been driven by the lack of immunological cross-protection against GI.2 afforded by the Cylap RCD vaccine (Zoetis Australia) or previous GI.1 infection (20), leading to a large number of susceptible individuals at the start of the epidemic. In addition, the ability of GI.2 to cause lethal infection in young rabbits at a much higher rate than GI.1 (8) implies that new cohorts of rabbits are becoming susceptible to severe outbreaks of GI.2 at an earlier age, which likely provides a strong competitive advantage for virus transmission in the field.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Rabbit Hemorrhagic Disease Virus 2 (RHDV2; GI.2) Is Replacing Endemic Strains of RHDV in the Australian Landscape within 18 Months of Its Arrival

Mahar

Hall

Peacock

et al. 2018

J Virol

106

122

View full text Add to dashboard Cite

(RHDV2; GI.2) is a pathogenic calicivirus that affects European rabbits () and various hare () species. GI.2 was first detected in France in 2010 and subsequently caused epidemics in wild and domestic lagomorph populations throughout Europe. In May 2015 GI.2 was detected in Australia. Within 18 months of its initial detection GI.2 had spread to all Australian states and territories and rapidly became the dominant circulating strain, replacing (RHDV/GI.1) in mainland Australia. Reconstruction of the evolutionary history of 127 Australian GI.2 isolates revealed that the virus arrived in Australia at least several months before its initial description and likely circulated unnoticed in wild rabbit populations in the east of the continent prior to its detection. GI.2 sequences isolated from five hares clustered with sequences from sympatric rabbit populations sampled contemporaneously, indicating multiple spillover events into hares rather than an adaptation of the Australian GI.2 to a new host. Since the presence of GI.2 in Australia may have wide ranging consequences for rabbit biocontrol, particularly with the release of the novel biocontrol agent GI.1a/RHDVa-K5 in March 2017, ongoing surveillance is critical to understanding the interactions of the various lagoviruses in Australia, and their impact on host populations. This study describes the spread and distribution of (GI.2) in Australia since its first detection in May 2015. Within the first 18 months following its detection, RHDV2 spread from east to west across the continent and became the dominant strain in all mainland states of Australia. This has important implications for pest animal management and for owners of pet and farmed rabbits, as there is currently no effective vaccine available in Australia for GI.2. The closely related RHDV (GI.1) is used to control overabundant wild rabbits, a serious environmental and agricultural pest in this country, and it is currently unclear how widespread circulation of GI.2 will impact ongoing targeted wild rabbit management operations.

show abstract

supporting

confidence: 75%

mentioning

confidence: 99%

Rabbit Hemorrhagic Disease Virus 2 (RHDV2; GI.2) Is Replacing Endemic Strains of RHDV in the Australian Landscape within 18 Months of Its Arrival

Mahar

Hall

Peacock

et al. 2018

J Virol

106

122

View full text Add to dashboard Cite

show abstract

“…The reciprocal positive association between RHDV and the rate of increase of RHDV2 was most likely the result of partial cross‐immunity, where some RHDV seropositive individuals are susceptible to RHDV2 infection. RHDV2 can overcome immunity from previous RHDV infection or vaccination (Le Gall‐Reculé et al, ; Neave et al, ; Peacock et al, ) and partial cross‐immunity has been recognized as a key process facilitating the incursion and coexistence of competing pathogen strains (Adams & Sasaki, ; Best & Hoyle, ). Several outcomes from the competition among strains under partial cross‐immunity are possible, including strain extinction, coexistence or strain oscillation (Lion & Metz, ; Restif & Grenfell, ).…”

Section: Discussionmentioning

confidence: 99%

“…However, other studies using more recent RHDV2 isolates report very high levels of virulence in both adult and young rabbits (Capucci, Cavadini, Schiavitto, Lombardi, & Lavazza, ; Neimanis, Pettersson, Huang, Widén, & Strive, ). Unlike RHDV (Robinson, So, Müller, Cooke, & Capucci, ), RHDV2 causes fatal infections in juvenile rabbits <5 weeks of age (Neave et al, ) and can also infect rabbits recovered from previous RHDV infection or vaccination (Le Gall‐Reculé et al, ; Neave et al, ; Peacock et al, ). Initial estimates of the impact of RHDV2 on wild populations from two sites in South Australia indicated a reduction in rabbit abundance of around 80% (Mutze et al, ).…”

Section: Introductionmentioning

confidence: 99%

Emerging RHDV2 suppresses the impact of endemic and novel strains of RHDV on wild rabbit populations

Ramsey

Cox

Strive

et al. 2020

Journal of Applied Ecology

View full text Add to dashboard Cite

Multi‐strain, host‐disease dynamics describe a system where multiple strains of a pathogen compete for susceptible individuals of a single host. The theoretical properties of these systems have been well studied, but there are few empirical studies in wildlife hosts. We examined the impacts of two novel strains of rabbit haemorrhagic disease virus (RHDV) recently introduced into Australia, one inadvertently (RHDV2) and one deliberately for rabbit biocontrol (RHDV‐K5), by analysing long‐term monitoring data for introduced European rabbits Oryctolagus cuniculus from 18 sites throughout Australia. We examined population‐level impacts using rabbit spotlight counts pre‐ and post‐arrival of the two strains. We also analysed serological data to determine potential interactions among the introduced and existing field strains of RHDV, as well as a pre‐existing benign strain of calicivirus (RCV‐A1). Serological analyses suggested that RHDV2 arrived in Australia during spring 2014 and spread rapidly through the Australian rabbit population within 2 years. Following the establishment of RHDV2, rabbit abundance was reduced by an average of 60%, with impacts most pronounced in South and Western Australia. In contrast, the deliberate release of RHDV‐K5 had little impact on rabbit populations. Although RHDV2 has spread rapidly throughout Australia, our serological analyses do not support the observation that RHDV2 is rapidly replacing existing field strains of RHDV, as was previously reported in Australia and Europe. Nevertheless, RHDV2 has negatively impacted the ability of RHDV and RCV‐A1 to spread within rabbit populations, most likely due to its ability to infect juvenile rabbits, thereby removing them from the pool of susceptible individuals available to be infected by competing strains. Synthesis and applications. The impact of the release of a novel strain of rabbit haemorrhagic disease virus (RHDV‐K5) for rabbit biocontrol in Australia has been suppressed by the emergence of a competing strain, RHDV2. Hence, the success of further releases of similar RHDV strains for rabbit biocontrol appears doubtful. Despite this, RHDV2 has suppressed rabbit abundances by an average of 60%, with impacts most pronounced in South and Western Australia. Whether the incursion of RHDV2 leads to the competitive exclusion of other endemic RHDV strains remains to be resolved. However, the existence of partial cross‐immunity could allow some level of coexistence between RHDV2 and RHDV strains, at least in the medium term.

show abstract

“…During the first RHDV2 outbreak emergency vaccination with classical myxomatosis/RHDV vaccine was reported to offer some protection, reducing mortality within seven to 15 days (Bárcena and others 2015); however, conflicting information has since emerged (Peacock and others 2017). Cross-protection between variants is variable and difficult to predict.…”

Section: Available Vaccines and Cross-protectionmentioning

confidence: 99%

Diagnosis and prevention of rabbit viral haemorrhagic disease 2

Rocchi¹,

Dagleish²

2018

In Practice

View full text Add to dashboard Cite

Rabbit haemorrhagic disease (RHD) is a highly infectious, often fatal, disease of rabbits and it is commonly found throughout the UK. RHD is caused by rabbit haemorrhagic disease virus (RHDV), also known as rabbit calicivirus (RCV). Since 2010, a new virus variant (RHDV2/RHDVb) emerged in Europe, and was identified in the UK in 2014; this new variant has now replaced the original virus in many countries. This article discusses the diagnosis and prevention of RHDV2 and the resources, such as diagnostic laboratories and vaccines, currently available in the UK.

show abstract

RHDV2 overcoming RHDV immunity in wild rabbits (Oryctolagus cuniculus) in Australia

Cited by 38 publications

References 26 publications

Rabbit Hemorrhagic Disease Virus 2 (RHDV2; GI.2) Is Replacing Endemic Strains of RHDV in the Australian Landscape within 18 Months of Its Arrival

Rabbit Hemorrhagic Disease Virus 2 (RHDV2; GI.2) Is Replacing Endemic Strains of RHDV in the Australian Landscape within 18 Months of Its Arrival

Emerging RHDV2 suppresses the impact of endemic and novel strains of RHDV on wild rabbit populations

Diagnosis and prevention of rabbit viral haemorrhagic disease 2

Contact Info

Product

Resources

About