Key Takeaways – Funnel-Web Spider Bites & First Aid
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Funnel-web spiders, especially Atrax robustus, are among the world’s most dangerous spiders, with venom that can be fatal to humans.
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Australia records the majority of serious funnel-web spider bites, though true funnel-web species are not found in Perth.
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Male funnel-web spiders are more dangerous due to their potent Robustoxin venom and greater likelihood of human encounters.
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Symptoms of a bite can include tingling, muscle twitching, nausea, sweating, breathing difficulties, and, in severe cases, coma or death.
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Immediate first aid involves calling 000 and applying a pressure immobilisation bandage to slow venom spread.
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Funnel-web spider antivenom is available in Australia and has significantly reduced fatalities since its introduction.
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Only males possess venom strong enough to cause death; female bites are typically less severe and have no recorded fatalities.
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Funnel-web spiders inhabit moist forests, gardens, rockeries, and tree crevices, but not typically in Perth.
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First aid training courses in Perth teach correct pressure immobilisation techniques for spider bites and other emergencies.
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Learning accredited first aid can be lifesaving, providing the skills to respond effectively to venomous bites before medical help arrives.
Funnel-web spiders are considered among the most dangerous spiders in the world. Their venom contains toxins that may kill humans. Unfortunately, these hazardous spiders are found in Australia. Let’s find out if there have been reported encounters and bites from funnel-web spiders in Perth. In addition, tips on first aid practices for spider bites will also be discussed.
Funnel-Web Spider Bite
The funnel-web spider has at least forty species. One is called Atrax robustus, responsible for all recorded deaths (13) and many medically serious spider bites, as stated by the Australian Museum. In addition, a study by The Medical Journey of Australia identified 77 cases of severe funnel-web spider envenoming. It included cases when antivenom was not yet available wherein:
- Six adults and seven children died
- 13 incurred non-fatal bites
When an anti-venom was introduced, 48 of the 77 cases were treated.
Symptoms of a Funnel-Web Spider Bite
The following symptoms may be felt with a Sydney funnel-web spider bite:
- Tingling around the mouth and tongue.
- Facial muscle twitching.
- Nausea.
- Vomiting.
- Profuse sweating.
- Salivation.
- Shortness of breath.
Agitation, confusion, and coma may also develop. These are associated with hypertension, metabolic acidosis, pupil dilation, generalised muscle twitching, and pulmonary oedema.
First Aid Treatment to a Funnel-Web Spider Bite
The dangerous health effects of a funnel-web spider bite may be prevented by:
- Call 000 for emergency help.
- Immediately respond to it with first aid, such as applying a pressure immobilization bandage.
- Treatment using anti-venom by a doctor.
Step 2 in the mentioned first aid management for a funnel-web spider bite only slows down the movement of the venom. The mainstay of the treatment is anti-venom.
How to Apply a Pressure Immobilization Bandage?
The best thing to do is to apply the funnel web spider pressure immobilisation technique. This first aid step applies not only to funnel-web spider bites but also to other animal bites and wounds. It may be done by:
- Having the victim lie down to prevent walking or moving around.
- Applying a firm bandage over the bitten area.
- Bandaging the entire limb tightly.
- Applying a splint to the limb.
Doing the above may be confusing to do, especially for non-first-aiders. Fortunately, these are now part of a first aid course at 123C Colin St West Perth 6005. In these accredited first aid courses, you may acquire the skills and knowledge to appropriately perform first aid in emergencies like spider bites containing venom.
The Male Funnel-Web Spider’s Venom
Only the male funnel-web spiders contain very toxic venom. It is called Robustoxin (d-Atracotoxin-Ar1), a unique component that severely affects the nervous systems of humans and monkeys.
Description of Robustoxin (d-Atracotoxin-Ar1)
The toxin produced by a male funnel-web spider is under the protein class, which is a low-molecular-weight neurotoxic polypeptide, according to the Toxin and Toxin Target Database (T3DB). It is in a liquid state and contains different compound types. Its route of exposure is through injection (sting/bite).
The Mechanism of Toxicity by the Male Funnel-Web Spider’s Venom
The funnel-web spider’s venom inhibits insect and mammalian voltage-gated sodium channels. Then, it binds to site 3 in tetrodotoxin-sensitive sodium channels. This process slows their inactivation and prolongs the duration of action potentials. When this occurs, repetitive firing occurs in autonomic and motor nerve fibres.
The Metabolism of the Male Funnel-Web Spider’s Venom
Removing the funnel-web spider’s venom may be done either by:
- Opsonization via the reticuloendothelial system (which involves the liver and the kidneys).
- Degradation through cellular internalization via the lysosomes (membrane-enclosed organelles that contain an array of digestive enzymes, including several proteases).
Health Effects of the Male Funnel-Web Spider’s Venom
The following circumstances may happen if a funnel-web spider bites you and injects its venom:
- Progressive hypotension.
- Raised intracranial pressure resulting from cerebral oedema.
Death from a funnel-web spider bite may result from the above effects.
The Female Funnel-Web Spider
According to the Australian Museum, the poisonous chemical found in a male funnel-web spider is not present in a female one. This may be why female funnel-web spider bites have not reported any deaths.
Why are there more spider bites from a male funnel web?
Aside from the venom being present only in the male funnel-web spider, they also wander at night during the warmer months (November-April) to look for females in their burrows. They often wander in suburban gardens, where they may be trapped inside houses or garages. These are familiar places where encounters with humans may happen, leading to a spider bite incident. Thankfully, this may still be treated with the help of a first aid response and antivenom.
The Funnel-Web Spider Antivenom
Fortunately, according to NPS Medicine Wise, the antivenom for this dangerous spider is also distributed in Australia. It contains an active ingredient injected to neutralise the effect of the funnel-web spider’s venom.
What Did a Funnel-Web Spider Antivenom Look Like?
The Funnel-Web Spider Antivenom is in a vial containing a freeze-dried powder. Before use, the solution is dissolved in sterile water and becomes colourless and clear, ranging from clear to slightly milky.
The Dose for the Funnel-Web Spider Antivenom
The dose of the antivenom is the same for both adults and children. It contains two vials that may be repeatedly injected as necessary.
Side Effects of the Funnel-Web Spider Antivenom
The following are considered common side-effects of the funnel-web spider antivenom:
- Allergic reactions.
- Rash.
- Hives.
Below are the possible serious side effects of the venom:
- Swelling of particular body parts such as the face, lips, or tongue.
- Wheezing, shortness of breath, or trouble breathing.
- Rapid, shallow breathing, cold, clammy skin, a rapid, weak pulse, dizziness, weakness, and fainting.
- Swellings on the skin may be pinkish and itchy.
- Fever, swelling, skin rash, joint pains, and swelling of the glands (may be in the neck, armpit, or groin).
These may occur anytime up to two weeks after the injection. If you experience any of the above, you are advised to inform your doctor immediately.
Identifying Funnel-Web Spiders
Let’s learn how to identify funnel-web spider species. The male funnel-web spiders are built more lightly than the females. In addition, they have the following characteristics:
- Medium to large.
- Black to brown body colour.
- Sparsely-haired and glossy hard carapace covering the front part of the body.
A male funnel-web spider may only have a body length of up to 25mm, while the females may reach over 35mm. In addition, males have slender legs, and a spur is located on the third segment of the second leg.
Funnel Web Spider Locations Australia
Below are each of the identified funnel-web spider locations or habitats where they live:
- Different forests (moist, dry, upland, rainforest).
- In or under rocks, rotting logs, crevices, rot and borer holes in rough-barked trees
- Rockeries and dense shrubberies in gardens.
- Holes in the ground.
People who garden and dig soil are advised to be cautious, as they may encounter funnel webs in burrows at any time of the year.
Funnel-Web Spiders in Perth and Other Locations
The above locations are not common in Perth. Instead, these funnel web spider locations and habitats are more available in other cities. In addition, the Western Australian Museum states that there are no true funnel-web spiders in the area. If you are wondering whether there are funnel web spiders in Victoria, the answer is yes. Funnel-web spiders on the Victoria side are found in the Dandenong Ranges.
Conclusion
The effects of an Australian funnel-web spider bite include symptoms that may lead to the development of severe ones. The danger of its bite may risk a victim’s life, primarily if the venom flow is not controlled while an antivenom is not yet available. This can be done by applying a pressure immobilization bandage, which is one of the skills that may be learned in a first aid course.