Scorpions

Some of the species in southern Africa

Parabuthus granulatus (Granulated thick-tailed scorpion)

The Granulated thick-tailed scorpion is large, about 115 mm in length and dark yellow to brown colour. It has a relatively small vesicle compared to other species. It is common from just north of Cape Town to northern Namibia and eastwards into the Northern Province. This scorpion is responsible for most of the serious cases of envenomation in South Africa. The venom is more toxic than Parabuthus transvaalicus.

Parabuthus stridulus

P. stridulus occurs in the Namid dunes from Oranjemund in the south to the Ugab River in the north. This scorpion has a shiny integument.

Parabuthus planicauda

This scorpion is commonly found under stones in the Boland, south coast and Karoo and is often misidentified as P. capensis.

Parabuthus capensis (Cape thick-tailed scorpion)

70 to 100 mm in length and a yellowish-brown colour although a black variety also occurs. It occurs just north of the Cape Peninsula northwards into southern Namibia and extending eastwards into the Eastern Cape becoming less common with this eastward distribution.

Parabuthus transvaalicus (Transvaal thick-tailed scorpion)

The Transvaal thick-tailed scorpion is large, about 140 mm in length and dark brown to black and hairy. It is reputed to be the second most venomous southern African scorpion. This scorpion can also be active in the morning and can be found in thatched roofs.

Parabuthus mossambicensis

This scorpion is very common in the far Northern Province and southern Zimbabwe and looks similar to P. transvaalicus.

Parabuthus villosus (Black hairy thick-tailed scorpion)

The Black hairy thick-tailed scorpion is large, about 140 mm in length and is black in colour. It is often seen during the day and is common from the Northern Cape and Namibia. Besides its normal prey it also captures lizards and mice.

There’s something about that viciously efficient combination of grasping pincers and curved sting that sparks terror in the human brain. But as long as you apply a smidgen of common sense, the chances of getting fatally stung by a scorpion in Southern Africa are in fact very low.

South Africa has quite a few scorpion species, but luckily for those of us who like the bundu and can’t resist turning over rocks, not many of our scorpions are highly venomous, and the risk of a fatal sting is slim. In the great majority of cases, stings cause pain that lasts no more than a few hours, with no further symptoms. The annual death rate from stings is only about one to four.

The sting’s the thingScorpions with broad pincers often look fearsome, but the pincers are just for grabbing; the sting’s in the tail. There’s a general rule of thumb to distinguish highly venomous scorpions from the mildly venomous (i.e. harmless to humans):

Highly venomous: thick tails, thin pincers Mildly venomous: thin tails, thick pincers

This rule applies to scorpions throughout the world.

In South Africa, it’s almost always scorpions belonging to the genus Parabuthus that cause fatalities. These scorpions typically inhabit dry areas, and like digging burrows in sandy soil, sometimes under rocks or at the base of vegetation.

How to avoid being stungFirst, do a bit of research on the area you’re going to, and find out if scorpions are endemic there. If they are, it’s even more important than usual to follow these precautions:

Wear shoes, particularly covered shoes and particularly at night. Most stings happen at night, to people going unshod.

Take care when lifting up rocks and fallen branches. It’s a good idea to wear sturdy gloves when doing camping chores like building a fire, moving rocks to put up a tent etc.

Scorpions and other fearsome beasts are a good motivation to set up and pack up camp while there’s daylight.

Shake out bedding before you get into it and when packing up. Do the same with clothes and shoes before dressing.

Don’t sleep directly on the ground – use a groundsheet at least. Your sleepingbag and tent also afford protection, but keep them zipped up.

Avoid sleeping right next to where scorpions may be hanging out, like at the base of thick vegetation.

Keep in mind that most stings occur in the period from October to March, with January-February, i.e. summer, as the peak.

What happens if you get stungIf a scorpion stings you, you’ll usually know about it. Even if you don’t actually see the culprit, you’ll feel the result: a sudden, often burning pain at the sting site. The pain may persist from a few minutes to a few hours, and there may be redness and swelling at the sting site. Fewer than 5% of stings result in symptoms requiring medical attention. Such symptoms, which suggest a serious sting, generally only start to occur after about half an hour, and sometimes only after several hours. These may include any of the following:

Abdominal cramps A burning sensation, or pins-and-needles, usually of the hands, feet, face and scalp. Hypersensitivity to tactile stimuli e.g. your clothing or bedding become irritating to your skin. Sometimes

you also become extremely sensitive to noise. Lack of co-ordination with stiff-legged or ‘drunken’ walking. Involuntary movements, tremors, muscle weakness High or low pulse rate Difficulty swallowing and excessive salivation i.e. drooling Difficulty speaking normally Excessive sweating Headache, nausea, vomiting, diarrhea Droopy eyelids Restlessness and anxiety Urine retention Difficulty breathing.

The severity of the sting will depend on several different factors: the species of scorpion, its size and level of agitation, and where it stings you. A bigger scorpion packs a bigger venom punch, as does a deeper sting.

Your health and age are also significant; stings are more dangerous for children and the elderly, and someone with cardiac or respiratory problems is at higher risk of a serious reaction.

What do to if you get stungThis is one time when you’ll be forgiven for killing wildlife*: it’s useful to keep the scorpion for identification purposes. But only try to bag the specimen if you can do so without risking another sting! Unless you’re an expert (i.e. you’ve done it many times before) don’t attempt taking the prisoner alive.

Clean the wound and apply a clean cloth, wrapped in ice or moistened with cold water, to the sting site. Take an over-the-counter painkiller like aspirin or paracetamol. If possible, get to the nearest hospital or doctor. Take note of any changes or additional symptoms that may occur.

No-one, except a medical professional trained to treat scorpion stings, should attempt to use any additional methods of treatment. Using the wrong kind or amount of anti-venom or other medications can be very dangerous.

It’s also important to reassure the scorpion’s victim that death from a sting is most unlikely. Sometimes people get into such a panic that they can even start to show false symptoms!

Differential diagnosis

The following possibilities must be considered when making a diagnosis: Alcohol withdrawal, Botulism, Diphtheria, Drug overdose, Encephalitis, Guillain-Barré syndrome, Hysteria, Meningitis, Myasthenia gravis, Myocardial infarction, Organophosphate poisoning, Poliomyelitis, Subdural haematoma, Tetanus.

Scorpionism management

Do’s.

1. First aid treatment is the application of a cold compress, if the hyperaesthesia will allow and an analgesic (Asprin, Paracetamol) to relieve pain and transport to a hospital.

2. Monitor cardiac and respiratory functions and treat as required.3. Patient with systemic symptoms, especially children and the elderly must be hospitalized for 24 to 48 hours.4. Immobilize and clean wound.5. Antivenom must only be administered in the case of severe systemic envenomation.6. Antihistamine and steroids only to be administered in cases of allergic reaction to antivenom. In the event of

anaphylactic reaction, which must always be anticipated, administer adrenaline.7. Atropine may be administered in cases of confirmed Parabuthus transvaalicus envenomation to control excessive

secretions.8. Intravenous administration of 10 ml of 10% calcium gluconate IV over 10 to 20 minutes may provide relief from pain

and cramp, but is only effective for 20 to 30 minutes.9. Administer a tetanus toxoid to prevent infection.10. Envenomation of the eyes must be flushed with water or any bland fluid (milk, urine). In severe cases antivenom can

be diluted 1 to 5 or 1 to 10 with water.

Don’ts

1. Do not use traditional remedies such as incisions, suction, tornique or the application of ointments.2. Do not use alcohol as it will only mask any symptoms.3. Do not administer antivenom if no signs or symptoms of severe envenomation presents itself.4. Do not administer spider or snake antivenom.5. Do not administer atropine to reduce salivation in the case of Parabuthus granulatus stings as it may lead to

unopposed adrenergic reaction.6. Do not administer barbiturates, opiates, morphine or morphine derivatives as this could greatly increase convulsions

and cause respiratory distress.

Research on local venomous species

Research in the Western Cape was done to improve the treatment for victims stung by Buthidae scorpions as it was felt that the treatment previously administered was not very effective. Eventually the scorpions responsible for the stings were obtained when patients were stung and it was established that in the majority of cases it was Parabuthus granulatus that was responsible. Once this had been established, a more specific anti-venom was developed. This proved very successful and patients thereafter recovered rapidly from stings. In just about all the cases that were researched, patients were stung under very similar conditions - at night, not wearing shoes on gravel roads

Dangerous scorpions: how to identify them

Highly venomous(see stings and venom)

Non-venomous

Thick-tail scorpions (family Buthidae). They have thick tails and thin pincers.

Thin-tail scorpions (families Scorpionidae, Ischnuridae). They have thin tails and broad, well developed pincers.

Parabuthus granulatus Hadogenes minor female.

Parabuthus granulatus sting Opisthacanthus capensis.

Uroplectes lineatus. Painful sting but not life-threatening. Opistophthalmus adustus.

Parabuthus capensis Opistophthalmus capensis

Parabuthus transvaalicus Cheloctonus sp.