It is summer and it is snakebite season. Close to 4,000 people are bitten by snakes in South Africa every year! Most of these bites happen in the early evening, largely between November and April and especially on hot rainy nights.

Snakes are not aggressive and usually bite in desperation – when stood on, accidentally cornered in a confined area or when someone attempts to kill one. They are very quick to escape when given the opportunity but many will not hesitate to bite when they feel in danger.

There is one exception – the Mozambique Spitting Cobra. This snake occurs from KwaZulu-Natal through Eswatini, Mpumalanga, northern Gauteng, Limpopo, Northwest Province and further northwards. It often accidentally ends up in homes when hunting at night and is known to bite people in their beds. Its not perfectly clear why these snakes do this but it appears to be somewhat of a feeding response with many people, including babies, being bitten in the face, on the chest, arms and hands. Its venom is potently cytotoxic and although fatal bites are uncommon, bites often result in a great deal of tissue damage.

The only treatment for serious snakebite envenomation is antivenom. The South African Vaccine Producers (SAVP), part of our National Health Laboratories, produce two snake antivenoms for Southern African snakes – a monovalent Boomslang antivenom that is seldom used, as the Boomslang rarely bites, and a polyvalent antivenom that is made from the venom of ten different snakes. It covers bites from cobras, mambas, the Rinkhals, Puff Adder and Gaboon Adder. Antivenom is only administered in hospitals as, like many other drugs, the patient may experience side effects. Up to 45% of patients that are treated with SAVP’s antivenom experience anaphylactic shock. Outside of a hospital environment, anaphylaxis can be difficult to manage and can lead to fatalities.

Since the onset of Covid, SAVP has experienced production problems, and over the past few years there have been multiple instances when antivenom was in severe short supply. Veterinarians have had great difficulty in sourcing antivenom, and many dogs died as they could not be treated after a snakebite.

The current situation is dire, and it appears that SAVP has no stock and nothing is being produced. Unfortunately, it is not possible to get any answers from SAVP, but in a recent email, they confirmed that they could not supply antivenom at present.

Most major hospitals in high-risk areas carry some antivenom, but often have far too little in stock. For a serious snakebite the initial dosage is around 6-12 vials of polyvalent antivenom and additional vials may be required.

An alternative antivenom called Pan African Premium is currently being imported under Section 21 of the South African Health Products Regulatory Authority and it appears to be a good alternative. It costs about the same as the SAVP polyvalent antivenom, but requires twice the dosage, thus double the price. It also requires a great deal of paperwork in order to purchase it.

It obviously makes far more sense to avoid snakebites and people are urged not to try and catch or kill snakes should they encounter one in their garden or house. Immediately ensure that kids and dogs are well separated from the snake and retreat at least five paces. Observe the snake and call a snake remover. There are over 800 snake removers’ country wide and you can easily find snake removers nearest to you using the free ASI Snakes App (http://bit.ly/snakebiteapp).

Keep gardens clean of building rubble and piles of rocks. An abundance of rodents, often attracted by pet food left outdoors in bowls or seeds from bird enclosures, will lure snakes closer as will water features, as many snakes eat frogs.

In the event of any snakebite, it is of utmost importance to get the patient to the closest hospital that has an emergency room. The free ASI Snakes App has further details on first aid for snakebite.

Johan Marais
African Snakebite Institute
johan@asiorg.co.za
October 2024