Australian Venom Research Unit
The Australian Venom Research Unit (AVRU) aims to provide world class expertise on Australia's venomous creatures, their toxins and the care of the envenomed patient. It has a number of research projects underway, some of which are described below.
Toxinology of Australian Sea Snake Venom Sea snakes are amongst the most venomous snakes in the world, but relatively little research has been done on these snakes or their venom. The Australian Venom Research Unit is undertaking a joint project with the Melbourne Aquarium to establish a reference collection of Australian sea snake venom and a sea snake genetic library. This unique resource will allow the analysis of intra- and interspecific variation in venom composition and gene construction. Such information will improve sea snake bite management, the knowledge of sea snake diversity, evolution and conservation status as well as potentially leading to the development of new disease treatments.
Bee and Wasp Stings in Australia Bee and wasp (hymenopteran) stings are one of the most numerically important envenomation injuries in Australia. The relatively recent arrival of European wasps in Australia has added another cause of morbidity, since these wasps are more likely to be involved in multiple stingings, due to their ability to sting more than once (unlike bees), their territoriality and the large numbers of individuals in the nests. Bee and wasp stings are also a leading cause of death related to venomous creatures. In Australia, deaths from anaphylaxis (severe allergic reaction) due to bee and wasp stings approximately equal deaths due to snakebite. The Australian Venom Research Unit has recently published papers on deaths from Hymenoptera stings based on Australian Bureau of Statisitics mortality data.
Characterisation of the Venom of the Irukandji Jellyfish, and Development of an Antivenom Carukia barnesi (known as irukandji) is a small cubozoan jellyfish found in the northern waters of Australia. It is thought to live mostly in the deep waters of the reef, although it may be swept onshore by prevailing currents. Stings have been recorded from Childers, Queensland to Broome, Western Australia. Although the sting itself is only moderately painful, it causes an illness called the Irukandji Syndrome (see below). It has been suggested that other jellyfish, such as the Jimble (Carybdea rastoni) may sometimes cause a milder version of this syndrome, which has also been described throughout the Pacific from Hawaii to China and offshore Florida, USA. With the assistance of Dr Peter Fenner, formerly the Chief Medical Officer with Surf Lifesaving Australia, and Mr Russell Hore, marine biologist with Quicksilver Connections in Port Douglas, AVRU is in the process of characterising the venom of these jellyfish, and investigating the biological activity of the venom fractions. Also involved in the Irukandji research is Lisa-ann Gershwin, marine biologist and doctoral student from James Cook University who is involved in catching and identifying irukandji. The Unit aims to produce an experimental antivenom for the treatment of the irukandji syndrome, and ultimately to make such an antivenom commercially available.
Investigations into Necrotising Arachnidism Necrotising arachnidism is the name give to a syndrome of blistering and ulceration of the skin that sometimes follows bites from spiders. In some cases, ongoing pain and tissue destruction occur, requiring extensive debridement and skin grafting. Several spiders have been implicated in this syndrome in Australia, including the white-tailed spider (Lampona sp.) and the black window or house spider (Badumna sp.), although definitive evidence is lacking. Both these spiders are commonly found in and around houses throughout Australia. Necrotising arachnidism is at present poorly understood in Australia. Research is hampered by the lack of reliability in reproducing necrotic effects in experimental models to date.
Epidemiology of Envenomation in Australia The Australian Venom Research Unit collates reports of patients receiving CSL antivenoms, and maintains a database on these cases. This represents an invaluable source of clinical and epidemiological data on envenomations for which antivenom is available. The unit is involved in collaborations with the Research Centre for Injury Studies, under the auspices of the Australian Institute of Health and Welfare, and the Monash University Accident Research Centre (MUARC) to investigate envenomation epidemiology using novel sources of data, such as hospital inpatient and outpatient records, coronial databases, general practitioner databases and ambulance records . AVRU collaborated with MUARC (Monash University Accident Research Centre) to produce an issue (Vol 35) of the quarterly "Hazard" publication of the Victorian Injury Surveillance System specifically devoted to venomous bites and stings in Victoria. This publication can be downloaded in full (Adobe pdf format) from the Published Resources section. These data sources are yielding a new level of understanding of the incidence and cost to the community of envenomation in Australia. They may also be used to investigate rare envenomations, such as scorpion stings, or envenomations of emerging importance, such as stings by the European wasp.
Snake bite in Papua New Guinea and Vietnam Snakebite is a significant medical problem in some parts of Papua New Guinea, with regional incidence rates as high as 563 cases per 100,000 population per annum. Rural mortality rates as high as 13.8 cases per 100,000 population per annum have been reported. At Port Moresby General Hospital the case fatality rate from snakebite over the ten years from 1992 to 2001 was 10.5% but recently that rate has increased to 18.3%. Paediatric case fatality rates between 1992 and 2001 were 14.6% but in the past year have risen to 25.9%.
Currently no national strategic plan exists for the identification of high snakebite risk regions or for the distribution of antivenoms based on empirical rather than anecdotal evidence. There are at least seven species of highly venomous snake distributed throughout Papua New Guinea (Acanthophis laevis, Acanthophis rugosus, Micropechis ikaheka, Oxyuranus scutellatus canni, Pseudechis papuanus, Pseudechis rossignoli and Pseudonaja cf. textilis). Although a polyvalent antivenom protective against all species is available, the high cost of this product and the higher rates of adverse reactions make it desirable to develop a system for reliable evidence-based distribution of lower cost monovalent antivenoms.
As the reduction in Australian snake bite mortality over the last century emphasizes, dedicated venom and antivenom research and production saves lives and alleviates suffering. Unfortunately the global tendency toward privatisating government-owned antivenom manufacturers, unleashing free market forces in countries with poor pharmaceutical regulation, threatens the humanitarian task of international snakebite control. Fake antivenoms, for example, are widely sold in Nigeria and in many countries only charlatans or traditional healers are available to manage snakebite. These difficulties, combined with the cessation or reduction in antivenom production by traditional manufacturers, such as Aventis Pasteur, have precipitated escalating snakebite mortality in Africa.
However there is room for optimism. The chosen theme of Papua New Guinea's 25th anniversary of Independence last September was "Walking Together", or Raka Hebou in Motu and Wokabaut Wantaim in Tok Pisin. This theme resonates strongly with our aspirations for regional and global partnerships towards snakebite control. Australia, with its distinguished record in antivenom research has the potential to play a leading role in international snakebite control. Countries with a high burden of snakebite, such as PNG and Vietnam, have well-organised national health systems effectively participating in global vaccination programs and disease eradication. Australian medical staff assist with snakebite management in regular regional toxinology teaching workshops and courses and by international hospital based exchanges, sponsored by Australian institutions. Indeed in the very week of PNG's Silver Jubilee celebrations two such snake bite workshops were held at PMGH by one of us. Nevertheless the need for global snakebite control is urgent and "action plans express no outrage". Unless affluent nations like Australia rise to this challenge, snakebite tragedies will be re-played daily throughout the Asia-Pacific region for want of a 19th century therapy. The AVRU and it's collaborators are developing an international snake bite initiative to address this global crisis. Come join us !
Sudden Death Following Brown Snake Bite Brown snake (Pseudonaja sp.) bite is the most common cause of death from snake bite in Australia. A number of these deaths have occurred within a relatively short period of time (less than 4-6 hours) following the bite, and have sometimes been associated with collapse and cardiac arrest, rather than the classic problems of neurotoxicity and coagulopathy. The mechanism for these deaths remains unclear, but may be related to a direct cardiotoxic effect of the venom. AVRU is interested in further study of the cardiovascular effects of brown snake venom components and the mechanism(s) underlying sudden deaths.