Summer and Stiletto Snakes
Snake expert, Johan Marais shares a bit about Stiletto snakes that become more active in the warmer weather:
I have addressed issues around Stiletto snakes and snakebite previously but with the recent warm weather we have already had a number of Stiletto bites in the past few days.
The genus Atractaspis – the Stiletto snakes – is distributed across much of sub-Saharan Africa and consists of 21 species. Bibron’s Stiletto snake (Atractaspis bibronii) is the common species in Southern Africa and is responsible for a significant number of serious snakebites in the region.
The Stiletto snake is nocturnal and is often found under logs and rocks or in disused termite mounds. It emerges on hot summer nights, especially after heavy rains. It is an irascible snake that bites readily. Individuals are usually dark brown to blackish brown with a similarly-coloured belly but in some areas individuals have a white belly. The head is small with small pig-like eyes. Sadly this snake is often mistaken for one of the harmless snakes and handled, invariably resulting in one or more bites.
This snake has large, moveable fangs in the front of the mouth, not unlike that of adders. The fangs can be protruded independently and the snake, when feeding on reptiles and small rodents, will protrude a fang and stab its prey. When handled, it may strike suddenly with slashing backwards movements. Many of the victims are children in rural areas that step on these snakes at night. Please note that this snake cannot be handled safely in any way – if it is gripped behind the head it will twist its head sideways and a fang will get you.
The venom of this snake is potently cytotoxic, causing severe pain, swelling, blistering and in many cases necrosis that could require amputation of a digit. The venom may also affect the lymph nodes. The pain sets in immediately and local swelling starts quickly. Within a day (in severe bites) there is discoloration and blistering. Stiletto snake venom also contains sarafotoxins, a group of cardiotoxic peptides that induce coronary vasocontrictions. While no fatal bites have been recorded from Bibron’s Stiletto snake, there have been a number of fatal bites from some of the other Stiletto snakes elsewhere in Africa. The venom yield of the Stiletto snake is small (1.3 – 7.4 mg compared to 100 – 400 mg in the Black Mamba) but the potency is comparable to that of the Boomslang in an LD 50 test.
There is no antivenom for the venom of this snake and patients are treated symptomatically. This has been documented in a scientific paper by Dr. Colin Tilbury and Prof. Bill Branch in which they state that victims require oral analgesics (paracetamol and codeine phosphate), elevation of the swollen limb and clear intravenous fluids.
Treatment must be conservative and surgical intervention delayed for at least 6 – 7 days. Antibiotics are not indicated except in cases where patients have self-inflicted cuts. Anti-tetanus must be given to all non-immunised patients.
While some bites result in alarming symptoms and severe local tissue damage, the majority of victims recover remarkably well provided that the above protocols are followed.