The illegal introduction of rabbit haemorrhagic disease virus in New Zealand

As part of a longitudinal study of the epidemiology of rabbit haemorrhagic disease virus (RHDV) in New Zealand, serum samples were obtained from trapped feral animals that may have consumed European rabbit (Oryctolagus cuniculus) carcasses (non-target species). During a 21-month period when RHDV infection was monitored in a defined wild rabbit population, 16 feral house cats (Felis catus), 11 stoats (Mustela erminea), four ferrets (Mustela furo) and 126 hedgehogs (Erinaceus europaeus) were incidentally captured in the rabbit traps. The proportions of samples that were seropositive to RHDV were 38% for cats, 18% for stoats, 25% for ferrets and 4% for hedgehogs. Seropositive non-target species were trapped in April 2000, in the absence of an overt epidemic of rabbit haemorrhagic disease (RHD) in the rabbit population, but evidence of recent infection in rabbits was shown. Seropositive non-target species were found up to 2.5 months before and 1 month after this RHDV activity in wild rabbits was detected. Seropositive predators were also trapped on the site between 1 and 4.5 months after a dramatic RHD epidemic in February 2001. This study has shown that high antibody titres can be found in non-target species when there is no overt evidence of RHDV infection in the rabbit population, although a temporal relationship could not be assessed statistically owning to the small sample sizes. Predators and scavengers might be able to contribute to localised spread of RHDV through their movements.

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Variable changes in nematode infection prevalence and intensity after Rabbit Haemorrhagic Disease Virus emerged in wild rabbits in Scotland and New Zealand

International Journal for Parasitology Parasites and Wildlife ◽

10.1016/j.ijppaw.2018.05.002 ◽

2018 ◽

Vol 7 (2) ◽

pp. 187-195 ◽

Cited By ~ 1

Author(s):

Alexander D. Hernandez ◽

Brian Boag ◽

Roy Neilson ◽

Naomi L. Forrester

Keyword(s):

New Zealand ◽

Disease Virus ◽

Nematode Infection ◽

Infection Prevalence ◽

Rabbit Haemorrhagic Disease Virus ◽

Rabbit Haemorrhagic Disease ◽

Haemorrhagic Disease

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Temporal dynamics of rabbit haemorrhagic disease virus infection in a low-density population of wild rabbits (Oryctolagus cuniculus) in New Zealand

Wildlife Research ◽

10.1071/wr03059 ◽

2006 ◽

Vol 33 (4) ◽

pp. 293 ◽

Cited By ~ 7

Author(s):

J. Henning ◽

D. U. Pfeiffer ◽

P. R. Davies ◽

J. Meers ◽

R. S. Morris

Keyword(s):

New Zealand ◽

Disease Virus ◽

Oryctolagus Cuniculus ◽

Temporal Dynamics ◽

Population Decline ◽

Adult Survivors ◽

European Rabbit ◽

Rabbit Haemorrhagic Disease Virus ◽

Rabbit Haemorrhagic Disease ◽

Haemorrhagic Disease

A longitudinal capture–mark–recapture study was conducted to determine the temporal dynamics of rabbit haemorrhagic disease (RHD) in a European rabbit (Oryctolagus cuniculus) population of low to moderate density on sand-hill country in the lower North Island of New Zealand. A combination of sampling (trapping and radio-tracking) and diagnostic (cELISA, PCR and isotype ELISA) methods was employed to obtain data weekly from May 1998 until June 2001. Although rabbit haemorrhagic disease virus (RHDV) infection was detected in the study population in all 3 years, disease epidemics were evident only in the late summer or autumn months in 1999 and 2001. Overall, 20% of 385 samples obtained from adult animals older than 11 weeks were seropositive. An RHD outbreak in 1999 contributed to an estimated population decline of 26%. A second RHD epidemic in February 2001 was associated with a population decline of 52% over the subsequent month. Following the outbreaks, the seroprevalence in adult survivors was between 40% and 50%. During 2000, no deaths from RHDV were confirmed and mortalities were predominantly attributed to predation. Influx of seronegative immigrants was greatest in the 1999 and 2001 breeding seasons, and preceded the RHD epidemics in those years. Our data suggest that RHD epidemics require the population immunity level to fall below a threshold where propagation of infection can be maintained through the population.

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Detection of RNA of rabbit haemorrhagic disease virus from New Zealand wild rabbits

Wildlife Research ◽

10.1071/wr01071 ◽

2002 ◽

Vol 29 (6) ◽

pp. 683 ◽

Cited By ~ 17

Author(s):

Tao Zheng ◽

Anna M. Napier ◽

John P. Parkes ◽

Joseph S. O'Keefe ◽

Paul H. Atkinson

Keyword(s):

New Zealand ◽

Disease Virus ◽

Rabbit Haemorrhagic Disease Virus ◽

Rt Pcr ◽

Specific Primers ◽

Tissue Samples ◽

Wild Isolate ◽

Rabbit Haemorrhagic Disease ◽

Polymerase Chain ◽

Haemorrhagic Disease

Rabbit numbers have returned to high levels in some areas of New Zealand following the initial spread of rabbit haemorrhagic disease virus (RHDV). We undertook to determine whether possible infection with an RHDV-related virus was interfering with the initiation of new outbreaks of rabbit haemorrhagic disease (RHD). RHDV RNA was detected by polymerase chain reaction with reverse transcription (RT-PCR) using RHDV-specific primers from tissue samples of wild rabbits that had been shot in the field. RHDV RNA was detected in 11 of 19 rabbits from an area of Otago where the rabbit population had greatly expanded and in 2 of 8 rabbits from the West Coast where outbreaks of RHD had not been previously reported. Among the 13 rabbits positive for RHDV RNA, 10 had detectable antibodies against RHDV. The nucleotide sequences of the isolates — a segment of the RHDV capsid gene — shared about 99% identity with that of the Czech strain V351 and that of a 1997 New Zealand wild isolate, but shared only about 84% identity with that of a European benign rabbit calicivirus. These results provide evidence for persistent infection of RHDV in rabbits.

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