Venom: A Killer or a Saviour? - Written by Nick Bedov

Think of a weapon that is capable of killing in a matter of mere seconds or torturing its prey for days. A weapon made from the fundamental building blocks of all living things, that can hijack your bodies processes and use them against you; this weapon is venom.

It has evolved on roughly 30 different occasion. It gives organisms a huge competitive advantage and this is the reason why thousands of animals are venomous – from snakes, arachnids, lizards, bees, mammals, fish, snails and even frogs – to name a few!

But before I go into further details about venoms, I need to point out the main distinction between venoms and poisons because they are not the same thing! Most people use the terms interchangeably because they are both toxins once they enter the body. The key difference is the fact that venoms are huge protein molecules that have to be injected, e.g. via fangs, stingers or micro-punctures. Poisons on the other hand, are small and simple molecules that can diffuse through tissues, such as skin – essentially they don't need to be injected. The other important difference is that the sole use of poisons is for defense, whereas, venoms evolved for killing prey, self-defense and to better adapt organisms to the ever changing environment in which they live. The latter being the case with the platypus, for instance.

Venoms evolved from mutated versions of the proteins that perform essential functions in almost every living organism on Earth therefore they are superior to poisons.

The toxicity of venoms, however, should not be confused with their danger. For example, snakes with the most toxic venom are found in Australia, however, they are not the most dangerous snakes as very few people actually die from these bites. In fact, more people die every year in Australia from falling in the bathtub than they do from snake bites; that's some dangerous bathtubs they have there! India's serpents, on the other hand, are not the most venomous, but the mortality rate is extremely high. Why? Well for one thing, there is less medicine available in India compared to Australia. Furthermore, most rural villages don't have an easily-accessible hospital. Thus, victims of an envenomation rarely get the proper antivenin on time.

Talking of which, we come onto the uses of venom. Quite obviously, to make antivenins one has to start with the actual venom but because of evolutionary relationships it is often possible to group certain “types” of venom together (e.g. hemotoxins or neurotoxins). This allows one polyvalent antivenin to work for many animals with similar toxins. There are cases, of course, when because of this generic approach, the antivenin simply doesn’t work and the venom is free to wreak havoc. Admittedly, I have myself lost a dear friend to the bite of a king cobra exactly for the aforementioned reason.

Nonetheless, venom is one of the most important sources for pharmaceutical development of drugs. Anyone taking medication for high blood pressure owes their life to the existence of the Brazilian pitvipers, as it was from the venom of these species that ACE inhibitors (like Captopril) were isolated. Saw-scaled vipers make blood-thinning venoms, which have been turned into an anticoagulant drug called tirofiban.

From the banded krait’s venom, α-bungarotoxin was isolated in the 1970s and is still used today to diagnose the neural disease, myasthenia gravis. Other drugs have been developed from neurotoxins in snake venom, which are used to treat Alzheimer’s Disease, as well as stroke and brain injuries. Bee venom is currently being developed as a cure for Parkinson’s disease and rheumatoid arthritis. The venom of the Gila monster provides a cheaper but more effective treatment for type II diabetes. And the list goes on… in fact this is estimated to be a multi-billion-dollar industry.

It is the great diversity of venom that allows scientists to test and match toxins with target diseases. But if the animals producing them were to become extinct, as thousands of species have already done because of human activity, we may lose the chance to discover the next wonder-drug that could save millions of lives.

Having conducted experimental research in this field (with many venomous species) I learned that each has evolved a truly ingenious delivery system and a potent array of toxins to match. Yet, again, without the conservation of these animals, there wouldn’t be a chance to study them. It is vital, therefore, if for nothing else, to protect wildlife for the benefit of unparalleled medical advances and our own success.

- Nick the Adventurer