Spiders and Spider bites
Spiders and spider bites
There are over 1800 known spider species in South Africa and many tend to be out and about in the warmer summer months. Most are pretty harmless and have an important environmental role helping to control pesky flies, mosquitoes and other flying insects. In most instances spider bites are no more troublesome than a bee sting.
But some spiders can be extremely venomous. Their bites can be really serious but fortunately are rarely fatal. As always, children and older folks are more at risk of complications.
To minimise risk it is good to be able to identify them – you need to be able to recognise the dangerous local spiders, know how to avoid bites and what to do if someone is bitten.
Four Dangerous Spiders in South Africa
SPIDERS WITH NEUROTOXIC VENOM: this affects the victim’s nervous system.
• Baboon Spider: Baboon Spiders – unmistakably large (up to 200 mm long), grey-back and very hairy – are found in houses in many parts of the country. They are usually fairly slow moving, not aggressive and easy to avoid.
Due to its large fangs the bite can be very painful but occurrences are fortunately rare. There is one species of Baboon Spider in the Cape that has Neurotoxic venom that causes symptoms like those of the Button Spider – paleness and sweating, pain and cramps, weakness in the limbs, cramp and vomiting.
If necessary, victims with severe symptoms should be hospitalised for treatment with anti-venom.
• Black Widow/Button Spider: Probably the most well-known South African spider, it is identified by the red hourglass shape on its shiny black body.
Button spiders usually found in dark places and occur through- out the country. Most bites occur when people accidentally disturb the spider in its hiding place.
The venom of Button spiders is neurotoxic and affects the victim’s nervous system. The bites are extremely painful and symptoms such as increased blood pressure, weakness in the limbs and cramps, flushed and sweating skin and possibly droopy eyelids and swollen lips soon appear. In bad cases the body can contort and shake uncontrollably.
Victims should be hospitalised for treatment with anti-venom and should recover after 48 hours.
For our useful list of Emergency Numbers click here.
SPIDERS WITH CYTOTOXIC VENOM: this destroys tissue and causes open wounds.
• Sac Spiders: Sac spiders have a black head and a yellow-brown, straw-coloured body.
An aggressive nocturnal spider, 5-16mm long, it bites at the slightest provocation. It is believed to deliver most spider bites throughout the country.
Most bites happen at night when a person disturbs or contacts a wandering Sac Spider. Venom of a Sac Spiders is cytotoxic. At first the bite may be relatively unnoticeable and later stings and itches mildly like a mosquito bite might do, accompanied by mild swelling and redness which then heals with general treatment. In some cases, after 2-3 days the bite location becomes painful, swells and an open wound develops. As there is no anti-venom for a Sac Spider bite, treatment aims to minimise infection and encourage healing.
Antibiotics assist reduce secondary infection.
In severe cases ulcerated wounds may develop and can take four weeks or more to heal but usually do so without scarring.
• Violin Spiders: occur all over South Africa.
Usually brown-yellow in colour, Violin Spiders have a violin-shape on the front part of their bodies. They are small, being 15-20mm long with a long spindly legs spanning up to 40mm.
Bites are rare and and tend to happen at night. Violin Spiders have cytotoxic venom. Bites initially seem small with burning accompanied by itching and may cause only mild swelling and redness with healing taking place with only general treatment. However, in some cases within 6-8 hours the site swells, reddens, then a white blister forms with red rings around it and the skin around the wound peels. The wound may stay open and, if untreated, infection and septicaemia can set in and tissue around the wound may die. Surgery may be needed to repair ulcerated wounds.
Seek medical help in all severe cases, especially if nausea, vomiting and fever set in. Treatment mainly aims to quell infection and hasten healing.
Precautions:
- Spiders often hide in rubble so keep your garden free of rubble piles.
- Button spiders tend to hide in dark places like under window sills – clean there often.
- Reduce clutter – spiders hide amongst items lying on the floor.
- Inspect curtains and bed frills for Sac Spiders – they form silky sacs in the pleats.
- Dust regularly and check behind pictures on the walls.
- Check your children’s beds at bedtime.
- Wear gloves when handling rubble of clutter in the garden or garage.
- Knock and shake your shoes out before putting them on.
- Empty the kettle and add fresh water before boiling for the first time in the morning.
- If washing is left hanging out overnight, check it carefully before packing away.
- If you have a problem with spiders at home, it may pay to have a pest specialist spray the house and furnishings to eliminate the spiders (it will reduce flies and mosquitoes as well). A do-it-yourself method is to spray insecticide around window frames and doors.
When Someone Is Bitten By A Spider
Spider bites are not always severe and it is best to keep calm. Most cases only require a painkiller, antihistamine and wound care.
In the instance of a button spider bite get the victim to hospital as soon as possible however, it is essential to get the to hospital immediately.
Children and the elderly should be seen by a doctor in all instances after a bite as they are more vulnerable.
Tips:
- If you can, photograph the spider to make identification and treatment easier (only try to catch the spider if you are sure to be able to do so without being bitten yourself).
- Use soap and water to clean the bite and cool it with an ice pack.
- Keep bites and wounds clean and apply an antiseptic,.
- If you can, keep the bitten limb elevated above the heart.
- If in doubt or symptoms become severe and ulcers develop, see a doctor immediately.
- A tetanus injection is recommended for all spider bite victims.
To learn more about Snakes and Snake Bites, click here.
To learn more about Scorpions and Scorpion Stings, click here.