Terry Slevin
There’s a kind of perverse pride I (and I suspect many) Australians harbour about growing up in a country which is home to 20 of the 25 most venomous snakes on the planet, including ALL of the top 10! Beyond snakes, we ‘boast’ spiders, jellyfish, flying and crawling insects, fish, octopus, ants, ticks, scorpions, centipedes, plants and assorted other critters that have the capacity to inject venom. All up, there are 66 species with such capacity.
So why is it that, rather than treating this as any other public health threat – to be measured, and managed – we revel in the threat? But let’s set that question aside for a moment.
Our friends at the Australian Institute of Health and Welfare (AIHW), with the lead being taken by the National Injury Surveillance Unit at Flinders University in South Australia, have produced a report quantifying hospitalisations due to these various beasties in 2017-18. And here is where I confess – I could not put this report down.
Like most Australians I’ve come across many of these magnificent creatures in the wild. And have my fair share of stories. Being a keen swimmer (and ocean swimmer when I can get to the sea) I’ve long been frustrated by the distorted perception of risk posed by sharks. Rarely does a week pass without someone telling me that swimming in the ocean is a foolish and risky pursuit, given the perceived ubiquity of these aquatic predators.
While shark attacks are not enumerated in the “Venomous bites and stings 2017 – 18 report”, almost every other such fear-inducing creature is, so let’s do what public health types do, and delve into the facts, as – hopefully an antidote to the media-headline-driven belief about what might send us to the hospital – or the morgue.
A total of 3,520 people were hospitalised due to contact with venomous animals and plants in 2017-18. In addition, another 1,943 people were hospitalised as a result of being bitten or crushed by snakes (venomous or non-venomous). Think constriction by pythons and the like, or bites from more common but non-venomous species like pet carpet snakes.
Data questions
Let’s get the caveats out of the way. This can only ever be a report based on the data that is recorded and reported. And let’s not pretend that the recording and reporting of such events is complete or perfect. It’s not hard to imagine a busy A&E department of a regional hospital on a busy Saturday afternoon dealing with sports injuries and MVAs not quite completing all the paperwork on a minor suspected spider bite or a difficult to diagnose but suspected allergic reaction to a wasp sting.
So, it is worth highlighting there are almost 5,500 cases turning up to hospitals each year. And possibly a similar number, maybe more, who don’t go to a hospital where the data is recorded.
And when thinking of context, another AIHW report released this week puts these numbers into a bigger picture. There were more than 532,000 injuries and 13,028 deaths reported in that same year, making these critters responsible for about 1% of those, with the big three coming as a result of falls, contact with objects (e.g. knives, tools, machines, sports equipment and guns) and transport related injuries.
And the biggest threat?
To the surprise of many, the biggest health burden is caused by the humble (not necessarily bumble) bee. Of the 19 deaths reported, 12 were due to bees and wasps. Seven were due to snake bites.
Bees, essential for the environment…but not so great for those stung by them!
Hospitalisations
Bees and wasps
There were 927 bee stings, and 329 wasp stings. In some cases, species were reported (honey bees – 36 – or paper wasps – 26) but for the most part they were ‘unspecified’. Interestingly, these were most common in the 45-64-year-olds age group. Gardeners perhaps?
Spiders
666 (ominous) spider bites were recorded. ‘Unspecified’ spider (‘I dunno Doc – it was a xxxxing spider’) was out in front with 300, closely followed by redbacks at 283. White tails and other necrotising spiders (38) and funnel webs (25) were also in the mix. Curiously only 26 cases were reported of antivenom being administered, all for redback bites. One can only guess this is a considerable under-reporting of antidote use.
Snakes
There were 606 snake bites. Brown snakes (215) were most common followed by ‘unspecified’ (208). Black snakes (83) Tiger snakes (65) and death adders (10) were also reported. Of the 606, only 161 were recorded as ‘principal diagnosis of toxic effect of snake venom’. It seems ‘dry bites’ are an explanation, as is the phenomenon of there being difficulties in identifying a specific toxic effect in the patient presenting. That might explain why there are only 86 cases of antivenom being administered, spread across brown (27), tiger (24) and other specified venomous snakes (23). Death adder (10) Taipan (7) and sea snakes (4) round out the list of known species.
As a helpful aside, the report tells us there are five monovalent snake antivenoms (brown, tiger, black, death adder and taipan) and a polyvalent (combining all five above) in a cocktail used when the species responsible for the bite is a mystery.
Brown snake, commonly spotted in open grasslands, pastures, and woodlands.
Ants and other arthropods
A total of 478 landed in hospital due to these creepy crawlies. Venomous ticks head this list (144) with ‘jumper and bull’ ants next (124) and then a few ‘other’ categories. Unspecified venomous arthropod (89) unspecified venomous ant (49) and other venomous arthropod – including venomous and urticating caterpillar (42) frustrate the detail-hungry researcher, and reader. Again, in this category the 45-64 and 65+ age groups are heavily over represented – again suggesting those of us spending time digging about in the garden might be more frequent ‘bitees’.
Venomous marine animal or plant
In total, 393 of us suffered for our coastal lifestyle. Stinging fish were out in front here (393) made up of 145 ‘other specified venomous animals and plants – including venomous octopus’, then stingrays (63 – hard not to immediately think of Steve Irwin), ‘specified stinging fish’ (59) and stonefish (30).
Jelly fish were another major sub category, totalling 73 cases. Irukandji jelly fish (41) ‘unspecified jellyfish’ (17) and box jellyfish (10) were listed. The ‘common as muck’ Bluebottle (Portuguese man o’ war) resulted in five hospitalisations but no doubt there were many thousands of unreported but painful stings. My own frequent experience of the – not terribly helpfully named – ‘stingers’ off the WA coast seem not to feature but I can attest they also cause thousands of painful stings every year that are rarely, if ever reported.
Bluebottle jellyfish – a common sight on Australian beaches
A favourite line among many pearls in the report is ‘unsurprisingly, the majority of hospitalisations due to contact with venomous marine animals and plants (72%) occurred in a large area of water (150 cases) or at the beach (131 cases)’. One wonders about the remaining 112 folk? I’m sure another data issue…
Sharks
While not covered in the AIHW report, an obvious comparator to these threats to Australians is the much-feared shark attack. Any such attack, fatal or otherwise, including many sightings in the absence of any harm coming to a single soul, seems to attract national headline news in Australia and often beyond.
Despite the enormous risk perceived from these extraordinary animals, in the similar period (in fact combining two years rather than one financial year July 1 2017 to 30 June 2018 so twice the time period when comparing the figures above) there were a total of 48 cases reported. Of those, there were two fatalities, 31 injuries and 14 ‘attacks’ resulting in no injury. Of those, ten were considered ‘provoked’, presumably linked to fisher folk attempting to catch or kill the shark.
Based on available data it seems in the period from 1791 to 2005 there have been a total of 639 attacks by sharks on humans in Australian waters, resulting in 190 deaths. My simple maths tells me that’s less than one death and just three recorded attacks each year off Australia’s vast coastline in that 214-year period.
Great white shark – majestic and unfairly maligned?
Crocodiles
Another prospect that horrifies many is that of an encounter of the croc kind. Again, this is one where most, if not all such attacks, attract blanket international media coverage.
But again, the numbers just don’t compare to the snakes and spiders report data. Drawing on media reports rather than hospital data there appear to have been four non-fatal and one fatal crocodile attack in Australia between 1 July 2017 and 30 June 2018.
And in the period from 1986 to 2019 there were 319 croc attacks – that’s closing in on 10 a year.
Context
A fundamental tenant of public health is to quantify a risk and put it in the context of other threats to our health and wellbeing. Of course, the psychological horror linked to the prospect of attacks from grand and deadly creatures like sharks and crocodiles is real and understandable. The extent to which they pose a substantial threat to us is far, far less than more common, and perhaps less frightening creatures.
And of course, these creatures contribute a relatively minor health challenge to the many other concerns that should and do occupy our attention. As mentioned earlier, In 2017–18, over 532,500 cases of injury resulted in admission to hospital in Australia. Suggesting the critters and creatures are responsible for about 1% of that burden of health trauma.
Action
So, should we ignore and dismiss concerns about the native threats to our safety in Australia? Certainly not. But is it worth us all being able to put these risks into context, and not be led by what bleeds on the 6pm news, or the lead story on our social media news feed?
I, for one, most certainly think so. Must be time for a swim!
Terry Slevin is the CEO of the Public Health Association of Australia, and is also Adjunct Professor in the School of Psychology at Curtin University and Adjunct Professor in the College of Health and Medicine at the Australian National University.