I believe Environment Australia is considering giving approval to the use of RCD baits as a biological control of wild introduced European rabbits in Australia.

I have researched the RCD issue in Australia for six years and it is my opinion RCD should not be spread on food baits in Australia.

Here are some of the reasons why I believe Environment Australia should not give its approval to the use of RCD baits in Australia.

Short list of some reasons why RCD baits should not be approved for use in Australia

In the future RCD/RHD may change its host range (no-one can predict with certainty the future host range of RHD)

· There have been negative effects on Australian birds of prey numbers due to a decline in the number of European rabbits in Australia- introduced wild European rabbits are a major food source of many Australian birds of prey. Wedge tailed eagle numbers have declined by 30-40% in parts of Australia in the past few years since the arrival of RHD and I believe a bird count is still underway in the Eastern states of Australia.

· No Environmental Impact Statement for the RHD virus has been prepared (a draft EIS was prepared but never formalised)

· Ear rot and protracted deaths of wild European rabbits infected with RCD have been observed in New Zealand (the only country ever to spread RHD on baits). There has been lack of funding to research why the ear-rot appeared in New Zealand. (See New Zealand Veterinary journal article)

· RCD/RHD baits may confer immunity to wild rabbits against RCD according to New Zealand researchers.

· Australia has a large number of animal species existing no-where else in the world - they may eat the RCD/RHD baits or rabbits heavily infected with RCD/RHD and consume large doses of live RCD/RHD virus and no testing using large doses of RHD virus fed orally to native Australian animals (or humans) has been conducted as far as we know.

· There is no monitoring program to monitor any effects of the use of baits on Australian animals.

· The increase in the amount of RHD in the environment due to the use of RCD/RHD live virus on baits may increase the likelihood of outbreaks of RHD in other countries where the disease is unwanted (the RCD/RHD virus is resilient and may travel on clothing and may be carried by migratory birds or sea mammals and on insects and dust particles. An outbreak of RHD occurred in Mexico in the 1980's and was thought to have arrived on frozen food).

· There are no safe vaccines to protect Australian native animals or humans should RHD choose to switch on in another host species.

· RHD is NOT species specific to the European rabbit. RCD/RHD most probably changed hosts to European rabbits from an unknown reservoir species and RHD has killed European brown hares (a different genus to the European rabbit). According to CSIRO tests, some animal species tested positive to RCD/RHD when injected with low doses of the RCD virus and their antibody levels were above the 30% cut-off level).

· At the time RCD/RHD was released, 4 out of 5 caliciviruses were known to infect humans and RCD/RHD antibodies were found in a Mexican laboratory worker according to the Australian RCD program (Hepatitis E [a calicivirus that kills a large percentage of pregnant women infected with Hepatitis E] has since been re-classified ).

· RCD/RHD is a relatively new virus, only having appeared for the first time in China in 1984. Little is know or understood about the RCD/RHD virus which kills a mammal often within 2 days - faster than Ebola. The disease has no cure and cannot be grown in vitro. Conventional wisdom dictates deliberately spreading such a disease on edible baits is foolhardy and dangerous and may expose many animal species to large, unmonitored doses of RHD with unknown consequences.

· The RCD/RHD virus in Australia has not been successful in some areas of Australia and the RCD virus escaped from open air testing on Wardang Island in 1995 (showing an inability of humans to contain the RCD/RHD virus). If there is a risk to other animals in Australia and the RHD virus has a low success rate, why spread the RHD virus which may be a potential threat to other animals?

Dr Alvin Smith and Dr David Matson, USA specialists in caliciviruses have warned Australian authorities of the dangers of the spreading the RHD virus but their warnings have been ignored.
See Dr Smiths website at the Oregon State University website to read his letters to Australian and New Zealand authorities. Also see letters from other international scientists who are very concerned at the spread of RCD/RHD in Australia http://www.iinet.net.au/~rabbit/sci.htm

Origins of the virus are unknown

Rabbit haemorrhagic disease appeared for the first time in China in 1984 in a shipment of Angora rabbits flown in from Germany. There are many theories about the origins of the RCD/RHD virus. Some researchers believe the RHD virus jumped species from another reservoir species in China and switched on in European rabbits to become the deadly heamorrhagic killer of mammals (ie European rabbits). There is research that shows the excreta of many animal species was used as fertilizer to grow food for other animals in China (including rabbits) at the time of the original appearance of RHD in China. Some researchers believe this is how the Angora rabbits in China acquired RHD (from an unknown reservoir species through ingestion of food contaminated with RHD virus). Some researchers believe a parvovirus was involved in the evolution of RHD (see the OIE report on RHD) and some researchers believe RHD emerged from a benign calicivirus and switched on to kill rabbits.

Whatever the truth is regarding the origins of RHD, no-one has yet proven how RHD emerged and no-one can predict which species this virus may infect in the future.

Koch’s postulate showed RHD was a parvovirus.

(1)Doug Gregg’s letter

In a letter to Elayne Ravji of New Zealand in August 1996, Dr Doug Gregg (Plum Island Laboratory, USA) said "When a new virus occurs in the world, any claims as to the cause must meet many standards. The classical standards which are still valid today were described by Koch in the 1800’s and are referred to as Koch’s postulate. That is, a disease agent must first be isolated in culture and then reintroduced into the host and the same disease should be reproduced. With RHD, this simply has not been accomplished except perhaps by the workers in the Peoples Republic of China. They claim to have isolated and passed the virus more than 10 times in cell culture and reproduce the same disease in rabbits from the cell cultured virus. No other laboratory has replicated their results. They claimed to have found a parvovirus and present considerable supportive evidence for this claim. I would refer you to several articles in the Technical review book published by the OIE on Viral Hemorrhagic Disease of Rabbits. OIE is the Office of International Epizootiology in Paris. It is an independent organization of member countries dedicated to the control of animal diseases. This book reviewed nearly all the work done on this disease at the time of publication. Each article was written by the primary investigator. All reviews were presented by the original investigators. Nearly all of our findings were published in this book. It is still available from OIE, and I strongly recommend anyone with a strong interest in this disease to study this reference book. "

"Now, perhaps this is the long answer. The short answer is that I agree with the Chinese workers that there is likely a parvovirus involved in the disease. This opinion is based on comparative pathology, electron microscopy, comparative immunology, immunohistochemistry, and in-situ hybridization. Many other workers in Europe, using less traditional methods of molecular biology claim that the agent is a calicivirus. Their results are interesting and cannot be ignored. The final answer awaits the fulfillment of Koch’s postulate in more than one laboratory. Until the agent can be isolated in vitro and the disease then reproduced, most scientists should be skeptical. "

(2) Dr David Matson et al’s letter to CDC Emerging Infectious Diseases journal re the use of RHD as a biocide - also refers to koch’s postulate determining RHD to be a parvovirus as well as inaccuracies in Australian human health data.
Reply to Drs. Capucci, Lavazza, and Mead
April-June 1998
http://www.cdc.gov/ncidod/EID/vol4no2/letters.htm

To the Editor: We are aware of Capucci and Lavazza's excellent work. Indeed, one of the best characterized calicivirus genomes is that detected in rabbit hemorrhagic disease (RHD); however, the virus' infectivity, pathogenesis, modes of transmission, reservoirs, survival in nature, host of origin, virulence factors, number of neutralization serotypes, and multispecies infectivity are poorly characterized. Propagating this virus in vitro could provide insight for addressing questions relevant to caliciviruses that cannot be propagated in vitro.

We are unclear about the confusion regarding Norwalk virus and feline calicivirus (FCV). Both are caliciviruses. Norwalk virus is a human pathogen. FCV is in a different genus (1) that includes strains infecting humans (2). We know of no documented FCV infections in humans nor of detailed studies to search for such occurrences, although some evidence suggests the possibility (3).

Capucci and Lavazza's remaining questions address the etiology of RHD, diagnostic reagents, and possible human infection. They report nine laboratory workers as antibody negative but do not report test results on persons at high risk, such as rabbit farm workers, nor do they mention having positive control human or primate sera. Koch's postulates have been fulfilled for RHD: a parvovirus was isolated in vitro and was cell-passaged 15 times; at a second laboratory, the parvovirus was identified in materials causing RHD (4,5). In Europe the parvovirus etiology for RHD was deemed hypothetical but has not been refuted on a scientific basis. The calicivirus consistently identified in European materials has not been isolated in vitro, and Koch's postulates have not been fulfilled. Are the parvovirus-associated outbreaks of RHD in Mexico and China (4,5) and the calicivirus-associated RHD outbreaks in Europe identical disease manifestations of two different viruses? Is RHD multifactorial requiring two or more agents? Is RHD caused by only a calicivirus or only a parvovirus? A calicivirus and a parvovirus can be isolated in vitro from the same fecal sample of a sick rabbit (N. Keefer, D.E. Skilling, A.W. Smith, unpub. data). Our comments on RHD diagnostic assays referred to those used in Australia (6,7) to screen humans and experimentally infected animals to support legalizing the spread of RHD in Australia and New Zealand.

Public health protection requires prudent avoidance of pathogens associated with risk of adverse outcome, not necessarily proof of causation (8). In this context, human health risk for RHD goes largely unaddressed. The deliberate introduction of a new disease agent (RHD) known to cause death in mammals requires prudence rather than proof of human illness, especially when the scientific literature includes reports that the agent has induced antibody reactions in a wide range of mammalian and avian species (6). Mead et al. (9) conclude, "No significant association between exposure to RCV and subsequent bouts of sickness could be demonstrated." Their recorded data do not support a statistically significant risk of illness because sample sizes in the monthly groups were too small for any meaningful interpretation. Mead et al. (9) state a "lack of any serologic reaction of the respondents," but a 50% cut-point was used for the competitive ELISA test, and some individual sera were repeated up to six times with percent inhibition reactions ranging from approximately 1% to 44% in one instance and 12% to 100% in another. Results were selected from these laboratory data and reported "lack of serologic reaction."

We derived our findings from data obtained under a freedom of information request. Mead et al. used the same data to support an opposite conclusion. Opposing conclusions "red flag" the quality of the study. In summary, the reporting of negative results of such a study cannot be used to support the important biologic, health, and political conclusion that humans are not at risk from infection with RHD.

We encourage a well-designed longitudinal study of persons at high risk of RHD exposure to answer conclusively whether RHD has infected humans. If "the rule" means that most humans exposed to RHD would become infected, we agree with Dr. Capucci "that infection is unlikely to be the rule," but transmission of equine morbillivirus, Rift Valley fever, and H5N1 influenza to humans is also "unlikely to be the rule" (10).

Alvin W. Smith,* Neil J. Cherry,† and David O. Matson‡ *Oregon State University, Corvallis, Oregon, USA; †Lincoln University, Christchurch, New Zealand; ‡Center for Pediatric Research, Norfolk, Virginia, USA References

1.Berke T, Golding B, Jiang X, Cubitt WD, Wolfaart M, Smith AW, et al. A phylogenetic analysis of the caliciviruses. J Med Virol 1997;52:419-24.
2.Smith AW, Berry ES, Skilling DE, Barlough JE, Poet SD, Berke T, et al. In vitro isolation and characterization of a calicivirus causing a vesicular disease of the hands and feet. Clin Infect Dis 1998;26:434-9.
3.Cubitt WD. Proceedings of the European Society of Veterinary Virology. Reading, United Kingdom: Reading University, Oct 1996.
4.Xu WY. Viral hemorrhagic disease in rabbits in the People's Republic of China: epidemiology and virus characterization. Rev Sci Tech, 1991;10:2393-408.
5.Gregg DA, House C, Meyer R, Berninger M. Viral haemorrhagic disease of rabbits in Mexico: epidemiology and viral characterization. Rev Sci Tech, 1991;10:2434-51.
6.Bureau of Resource Sciences, Australia. Rabbit calicivirus disease. Canberra, Australia: Australian Government Printing Office; 1996.
7.Collins BJ, White JR, Lenhaus C, Boyd V, Westbury HA. A competition ELISA for the detection of antibodies to Rabbit Hemorrhagic Disease Virus. Vet Microbiol 1995;43:85-96.
8.Brad-Hill A. The environment and disease: association or causation? Proceedings of the Royal Society of Medicine, 1965;58:295-300.
9.Mead C, Kaldor J, Canton M, Gamer G, Crerar S, Thomas S. Rabbit calicivirus and human health. Canberra, Australia: Department of Primary Industries and Energy, Australian Government (Released under the Official Information Act). Report of the Rabbit Calicivirus Human Health Study Group; 1996.
10.Vogel G. Sequence offers clues to deadly flu. Science News. Science 1998;279:324.

Precautionary Principle

Australian scientists have not proven RHD will not infect any other species except the European rabbit. In fact it is quite likely RCD has emerged from a host species somewhere in China and RHD is also known to have killed European brown hares. Therefore there are three species RHD already infects that we know of (European rabbits, European brown hares and an unknown original host species) and RHD antibodies were found in a Mexican laboratory worker according to the Australian RCD program (which has been closed down) .

Australia has many unique species of animals found nowhere else in the world. RHD has never been fed to these animals in large quantities over time to see if they would become infected with RHD.
Early CSIRO tests were conducted on a statistically insignificant number of each of a range of Australian native animals and the doses of RHD given to these animals was a deliberately low dose so as not to provoke a reaction. Even so, some animals tested in these experiments tested positive to RHD by CSIRO’s own criteria (ie there antibody reactions were above the 30% cut-off).
Humans have not been deliberately infected with RHD in large doses to look for any responses such as abortive effects of the virus in women or any other illnesses that may occur. A re-analysis of the human health data based on data I obtained under FOI and sent to the USA showed there may be some ill-health in humans subjected to large amounts of RHD virus.

Lack of Funding for testing Australian Native Animals / RCD Program termination.

The RCD program has ceased at the time when RCD baits are being considered as a biocide by the NRA in Australia. If a deadly haemorrhagic virus is to be spread across a continent on edible baits, it is appalling that the only monitoring program in Australia was closed down prior to the possible approval and spread of RCD baits.

RCD bait use in New Zealand coincides with Ear-rot and protracted death of European wild rabbits.

The New Zealand Veterinary Journal published research showing the appearance of ear-rot in wild rabbits infected with RCD from consuming RCD baits. Rabbits affected with RCD were seen to take weeks to die while their ears rotted away. This phenomena has been seen no-where else in the world other than New Zealand and lack of funding prevented the researchers who published this paper from conducting further tests to find out why the ear-rot was occurring . Could the "ear-rot" effect occur in Australian wild rabbits? If so, this would be seen as inhumane and not the "fast quiet death" as promoted by the RCD program. Could the "ear-rot" occur in other native animals consuming baits such as kangaroos? If New Zealand is to considered as a testing ground for RCD baits, the lack of initiative to find why the "ear-rot" effect occurred in wild introduced rabbit in New Zealand is a great concern for Australia if we intend to use RCD baits here. (I have provided the NRA with the NZ ear-rot article which also appears on my website http://www.iinet.net.au/~rabbit/rabbit.htm )

RCD Antibodies found in other animals in New Zealand

High levels of RCD antibodies were found in animals known to consume wild European rabbits in New Zealand. Antibodies are often a sign of the immune system fighting infection. Here is an excerpt from the article concerned.

"Richard Heyward1, John Parkes2 and Grant Norbury1. Landcare Research: PO Box 282, Alexandra; P0 Box 69, Lincoln. Email:Heywardr@landcare.cn..nz

Feral cats, ferrets, harrier hawks, and to a lesser extent hedgehogs, use rabbits as a food source either by scavenging or predation By eating rabbits that have died of, or are infected with, RHD they may produce antibodies in response to the virus, as occurs in foxes (e.g., Leighton at at 1995, Journal of Wildlife Diseases 31: 541-44) Hares, a close relative of the rabbit, may be at risk from cross-infection. Our objective was to determine whether any predators, scavengers, or hares produced an antibody response when exposed to rabbits with RHD.

We collected serum samples from predators and scavengers, from an area of mass biociding in the Mackenzie Basin and from spot-baited areas in North Canterbury, during February and May 1998. The samples were tested for RHD antibodies using a competition ELI SA test at' 1:40 diluton. We also tested small numbers of cats, ferrets, and hares from areas without RHD.

Fifty-three percent (n=51) of cats, 10% (n=51) of ferrets, 11% (n=18) of hawks, and 3%(n=30) of hedgehogs were seropositive (Those with greater than 50% inhibition).

RCD baits may immunise wild rabbits

Veterinary Microbiology 1999 March 31;66(1):29-40

Serology of rabbit haemorrhagic disease virus in wild rabbits before and after release of the virus in New Zealand. O'Keefe JS, Tempero JE, Motha MX, Hansen MF, Atkinsona PH AgResearch, Wallaceville, Upper Hutt, New Zealand. okeefej@maf.govt.nz

Rabbit haemorrhagic disease virus (RHDV) was illegally released in New Zealand in August 1997. The initial release and spread of the virus was conducted by landholders in an effort to reduce costs associated with more conventional control methods (poisoning and shooting). Serum was collected from wild rabbits throughout the Otago region prior to the release and from 13 sites in the months following the first epizootic.

Following the occurrence of the first RHDV epizootic on 13 pastoral farming properties a range of survival rates was found. The major factor influencing the survival rate was found to be the method of release, with widespread use of carrot or oat baits containing RHDV resulting in poor kills.

Widespread use of baits also resulted in higher levels of antibody in surviving adult rabbits with a higher proportion of adult females surviving the epizootic, compared with properties where the disease was allowed to spread naturally. A correlation was found between survival rate and the percentage of surviving adults with high levels of antibody.

These results suggest that poor kill rates are not due to poor spread of the virus, that the large-scale use of baits resulted in protective immunisation and that rabbit control should in the future be achieved through establishing naturally spreading epidemics rather than widespread use of baits.

Lack of an EIS and the Australian birds of prey

Environment Australia has not commissioned a formal Environmental Impact Statement with regard to RCD or RCD baits (I realise there was a draft EIS by Dr Brian Coman but this draft was never formalised) . There have been reports from Birds Australia that numbers of Wedge-tailed eagles have declined 30-40% in parts of Australia and a bird count is apparently still underway. Wedge-tailed Eagles rely heavily on rabbits as a major food source as do many other diurnal birds of prey (refer draft EIS by Brian Coman). Birds also seemed to be more likely to have antibody reactions to RCD in the RCD testing by CSIRO referred to in the 1996 RCD report. If RCD made some birds of prey ill or caused abortive affects, where is the research or study to show whether this is so? According to past BRS reports, wedge-tailed eagles have ceased to breed for years in some parts of Australia since the introduction of RCD (eg Strzelecki Ranges).

Starvation diet
by Rachel Nowak
New Scientist 31st October 1998
Raptors are paying the price as Australia wins the war against rabbits

THE deadly calicivirus that has devastated Australia's rabbits may be having a knock-on effect on indigenous wildlife. Wedgetailed eagles (Aquila audax) have not bred for the past three years in the Strzelecki Creek region of South Australia, according to a study from the Australasian Raptor Society and the state's government. Rabbits had become the food of choice for many birds of prey so the researchers suspect that the failures are due to food shortages.

The calicivirus reached the mainland in 1995 from Wardang Island, off South Australia, where it was being tested as a method of controlling rabbit numbers. It spread quickly across the country, decimating rabbit populations. But from the start, conservationists have worried that either the virus itself, or the shortage of rabbits for food, would affect Australia's natural fauna.

Those fears now appear to be being realised-although to date there is no evidence that any species is seriously threatened. The overall abundance of birds of prey has declined in areas affected by the calicivirus, according to Birds Australia, an organisation that uses volunteers to estimate bird populations. Brown falcons (Falco berigora) are the hardest hit, with the number of sightings down by half over large swathes of temperate Australia.

Curiously, the number of roadside sightings of wedge-tailed eagles has doubled during the summers since the introduction of the virus. But that may be due to changes in the bird's behaviour bought about by hunger, claims Will Steele, a project officer with Birds Australia in Melbourne. He suspects that the eagles are being driven to feed on road kills.

Roger Pech, a population ecologist in Canberra with the Wildlife and Ecology division of CSIRO, Australia's national research organisation, is sceptical of the Birds Australia data. For long-lived raptors it should be too early to see the effects of the reduction in rabbits, he says. But breeding success could be hit more quickly. CSIRO's own studies of wedge-tails around Lake Burrendong in New South Wales have so far been inconclusive. In the first year following the virus outbreak, most of the eagles bred successfully. This year however, breeding activity has fallen markedly. Another CSIRO study in the same region has found early indications that more brushtail possums, a native species, are being eaten by foxes and feral cats since the rabbit decline. "In the short term, it's a real concern that feral cats and foxes will eat the indigenous species," says Pech. But the reduction in rabbits may in the long term be beneficial to native animals. In the Journal of Applied Ecology (vol 35, p 434), Pech describes a model of prey-predator interactions which predicts that the lack of rabbits will eventually lead to a reduction in the number of introduced predators such as foxes and feral cats.

End

NZ Ministry of Health and NZ Association of Scientists said No to RCD/Secrecy of RCD bait consideration by the NRA

The New Zealand Ministry of Health and the New Zealand Association of Scientists both submitted reports to New Zealand authorities opposing the introduction of RCD/RHD into New Zealand. New Zealand decided NOT to adopt RCD as a biocide but farmers illegally imported the disease and the New Zealand Government backed down from its earlier decision based on science. The New Zealand Government capitulated to vested interests who went to the extreme of breaking New Zealand laws to import the RCD virus. Australians and overseas scientists never had an opportunity to submit submissions prior to the escape of RCD from Wardang Island in an open public consideration process and much consideration of whether to legalise RCD baits by the NRA is being conducted in secrecy and behind closed doors by the NRA. This does not allow for any virologists or overseas scientists interested in this issue to examine any of the data being presented to the NRA for faults and flaws.

The RHD virus is not a chemical but a deadly live virus which may change hosts at some future date and there should be full and open discussion (including public input) on the RHD bait issue / Environmental concerns allowing submissions by the Australian public and interested parties.

No vaccines - difficulty in vaccine manufacture

There are no vaccines to protect any species other than rabbits from RHD/RCD. CSIRO could not grow the RHD/RCD virus in vitro and most laboratories have the same problem. To make the present RCD vaccine to protect rabbits, live rabbits are infected with RCD and they are killed. The RCD virus is taken from their livers and is killed and used as a basis for the vaccine used to protect pet and meat rabbits etc. Environment Australia should consider the difficulties in vaccine manufacture that would occur if an Australian animal species was found to be susceptible to RCD/RHD. Also, how would such a vaccine be spread? Would food baits be used? How difficult would this be? All these issues need to be addressed by environment Australia.

Biowarfare - who is responsible if RHD/RCD causes Australian animals or humans to become ill?

Despite the existence of the Biological Control Act and the assertion that the benefits of RCD/RHD outweigh the risks (according to the 1996 BRS report on RCD), there are concerns in the scientific community that those responsible for spreading an agent of biowarfare be held accountable for their actions across international boundaries.

If RCD/RHD is proven to cause illness in people or animals and Australian authorities have contributed to the spread of the disease, will Australian scientists and officials be held personally responsible for the action of spreading a little known deadly virus across a whole continent? This is a factor for the Australian authorities to take into account especially since the use of RCD/RHD baits will be transmitting the RHD/RCD virus on edible baits which is a widespread and unmeasurable way of spreading RCD/RHD virus. Injecting virus into live rabbits is more species specific than broadcasting baits that may come into contact with so many animal species.

FOI requests

I am currently trying to obtain RCD bait information under FOI to send to scientists overseas and within Australia for scrutiny. I would like to obtain the raw data from RCD bait testing as well as the information I have been denied before the RCD baits are considered for legalisation in Australia. I am in my second year of trying to obtain the RCD bait information and I have a lawyer helping me. I have continually been denied access to the RCD bait data. If the RCD baits are safe, why all the secrecy? Environment Australia should be concerned about this secrecy and Environment Australia should be doing my job and obtaining the raw data for consideration by scientists unaligned with those whose reputations rest on the RCD saga. The safety of Australian animals and humans should come before egos or the possible convoluted science of those who are trying to make names for themselves out of this sorry saga. In the meantime, RCD has not been successful in many parts of Australia and it would do no harm not to approve the RCD baits until more is known about how Australian scientists are attempting to guarantee no harm to any other species in Australia from the spread ad hoc of RCD/RHD on edible baits (bring all the RCD bait data and the research out into the open public domain). People need to know whether the RCD bait testing raw data is being interpreted in a biased manner or whether the raw data itself is flawed or showing so many inconsistencies, it cannot be relied on as a basis to make any decisions at all.

Threats to our food supply.

At one time a British politician’s daughter ate a burger on TV to allay public concerns about Mad Cow Disease (the message was British beef was safe to eat) - later CJD in humans posed such a threat, British beef was regulated and CJD and Mad Cow disease have since been considered a threat to the health and well being of humans and animals as well as a threat to animal husbandry/agriculture.

The RCD program once said it was safe to eat rabbit meat infected with RCD/RHD. They later withdrew this statement. If RHD/RCD is spread on food baits in agricultural areas, it is quite likely our food may be dosed with increased levels of RHD virus. The food of animals in the Australian web of life will also be dosed with large doses of RHD virus and it is quite likely the virus may cause illness in Australian humans or animals (no-one can promise this won’t happen). Therefore commonsense would dictate we don’t spread RHD virus on food baits.

Brian Cooke’s letter/report to the NRA (14/2/2000) and scientific concerns about cross species transmission of RHD/RCD

I believe the NRA is making decisions on reports/letters which answer none of the questions raised by overseas scientists as to the safety of RCD/RHD on baits or otherwise. I have a copy of a report by Brian Cooke to the NRA on a CSIRO letterhead which states, for example (in answer to questions posed by the NRA),

1.’The application does not contain the information the NRA requires"

Brian Cooke’s answer says "To the best of our ability we have provided NRA with sound scientific advice on the efficacy and environmental safety of bait delivered RCV. As the crux of your letter appears to be that Rabbit Calicivirus Disease (RCD) will cross to non-target species if these are orally exposed to RCV treated bait. We stress again that the only known species to be vulnerable to RCV is the European Rabbit. The evidence for such an extremely narrow host range is overwhelming."

Brian Cooke is wrong. RCV is known to have killed European hares (a different genus to European rabbits) and the virus probably originated from an unknown reservoir host species. CSIRO’s own tests showed other species reacted to being injected with RHD (so much so that some of them tested POSITIVE under CSIRO’s own testing criteria. Not every animal may drop dead from RHD and no-one knows what ill-health RHD may cause in other species.(there have been no funded searches for evidence of RHD infection in other animal species in the wild areas of the world as far as I am aware). Lack of evidence should NEVER be used as evidence that an event (such as cross species infection) has or has not occurred. RHD only emerged in 1984 and CSIRO testing on Australian and domestic animals was deficient. The CSIRO RCD tests used a statistically insignificant number of each species (only 4 of each species) and immunocompromised and young and old animals of each species were not tested. Also, the amount of RHD virus used to infect Australian animals was deliberately low (the opposite of the unregulated amount of virus that may be consumed if RHD virus is spread on baits) and I believe the testing used injection rather than baits as a method of infecting these animals.

Professor David O. Matson is world authority on caliciviruses . He wrote to me (in reply) that he thought RHD may cross species barriers to infect other animals.

Dr Matson said "My comments are as follows:

1) The fact that the rabbit calicivirus is killing 90% of rabbits is a clue that this agent is new to rabbits. The rabbit population could not survive if 90% mortality was the routine outcome of exposure. We don’t know from which species the virus arose. I will say that I don’t think the rabbit hemorrhagic disease calicivirus release will work in Australia, or anywhere. Genetically resistant and immune rabbit populations will arise and repopulate the same areas unless a "second hit" mechanism is used to eliminate them.

2)The close proximity of rabbits to other mammals, and other families, increases the possibility of transmission of the agent to species other than rabbits. One scenario would be the consumption of a sick rabbit by a dog. In this instance, one could expect an inoculum to the dog far exceeding that used in the CSIRO experiments. Because inoculum is an important determinant of outcome of exposure, barriers to infection that might have been apparent in experimental settings may be overcome in wild exposures.

3) All caliciviruses share some common genomic features. We anticipate that those common features will result in common utilization of replicative mechanisms in the host cell. We know already that some calicivirus strains can replicate in a wide range of hosts. This suggests the possibility that a virus like the rabbit hemorrhagic disease calicivirus at a minimum will be able to replicate in livers or other tissues from mammals other than rabbits.

4) We know that caliciviruses affecting humans are genomically diverse. In fact, on the basis of genomic comparisons it is difficult to draw the line between different clusters of human calicivirus strains. Rabbit caliciviruses have not been as well characterized as human and other calicivirus strains. We do not know the limits of antigenic types in the rabbit hemorrhagic disease calicivirus and we don’t know the diversity of a population of wild rabbit hemorrhagic disease calicivirus strains. Knowledge of this diversity would be one prerequisite to releasing any calicivirus strain deliberately.

5) I am not fundamentally opposed to the release of biologic agents for controlling exotic species. I am opposed to such releases being poorly executed, as was the case for the rabbit hemorrhagic disease calicivirus release in Australia. I am hoping that the New Zealanders will learn from the Australian mistakes and delay release in their country until proper methods are in place, as well as the Australian government refusing to authorize deliberate rabbit hemorrhagic disease calicivirus release."

The New Zealand Ministry of Health implied that CSIRO data promoting the species specificity of RCD was lacking when they stated in October 1996 "The data presented by CSIRO on the cross-species transmission of RCD is preliminary in nature and of rather poor quality. Better data would be required to enable the concerns expressed by Prof Smith to be addressed."

Dr Alvin Smith (Head of Oregon State University’s Laboratory of Calicivirus Studies) also made some observations that should be considered by Environment Australia.

Dr Smith said "1. The origins (mutation or non-rabbit host) of RHD in China in 1984 remain unknown.

2. The genetic determinants and mechanisms resulting in a rapid and bloody RHD induced death are unknown.

3. The modes of RHD transmission across ocean channels and between continents are unknown.

4. The mechanisms of RHD transmission, which is sometimes rapid and sometimes leap-frog (hundreds of kilometers), are unknown.

5. The reason for failure of RHD to transmit even under contact conditions in fenced enclosures (Wardang Island) are unknown.

6. The host range of RHD is virtually certain to extend well beyond rabbits (Geelong experiment showing 2-17 fold antibody increases in 11 test species using purported subimmunogenic virus doses) but remains unknown.

7. Diagnostic reagents for RHD lack the specificity and sensitivity to carry out adequate epidemiologic assays, particularly in non-rabbit species including humans.

8. RHD vaccines for rabbits in Spain are reported over time to have become less protective.

9. RHD vaccines are not available to protect any non-rabbit species at risk, including humans.

10. RHD has not been shown (using proven and acceptable scientific methods) to be caused by a calicivirus alone; therefore, the infectious makeup of RHD is unknown.

11. RHD cannot be propagated in cell culture. Yet, that was a stated essential CSIRO requirement to be met before infectivity studies were to be carried out (1994 BRS report).

12. RHD may have already impacted human health (see Dr. Cherrys' Report #1000) and the extent of the suspected threat to human health is unknown.

13. In Australia, RHD is uncontrollable, unpredictable, and often unreliable as a rabbit control agent. Thus, the reality of RHD now loose in the countryside has turned virtually every Australian/New Zealand RHD program prediction and pronouncement into a statement of foolishness. "

I hope Environment Australia does not give its approval to the RCD baits. Controlling rabbit numbers and spreading RHD in Australia are two entirely different matters and rabbit control does not mean that Australia has to spread RHD. My own personal belief is that there are a small group of scientists in Australia who believe they can determine what a virus may or may not choose to infect. These scientists are NOT experts in caliciviruses and may have a false sense of security that Myxomatosis has been used without documented ill effects to non-rabbit species in the past and therefore other viruses such as RCD may also be spread around like water without the need for concern. These scientists have not proven RHD is safe to spread across the Australian continent and as custodians of the survival of Australian animals, I believe Environment Australia should err on the side of caution and common sense and should NOT give their approval to the use of RCD baits in Australia.

Kind regards,

Marguerite Wegner.

Please find attached an article about the disbanding of the Calicivirus Management Group and an article by Dr Alvin Smith from Nature Australia Winter 2000. Also please find attached my letter to Dr Brian Cooke and a letter I received in reply from Dr Brian Cooke. Note that he would rather not have me place his report on the internet (and he is sole signatory of the report) and yet this type of report is the basis for decisions made by the NRA. His reference to peer reviewed papers being more appropriate to the public domain is irrelevent because peer reviewed papers do not predict what is happening at the leading edge of science (including what species a virus will or will not infect in the future). There are no peer reviewed papers that have foreseen current outbreaks of Mad Cow disease, foot and mouth disease or any other viral epidemic. Such epidemics just happen and peer reviewed papers are written later.


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