Kaushik Bharati, PhD
There are approximately 3000 species of snakes in the world, of which around 10% are venomous. In the Indian context, there are over 270 species of snakes of which approximately 60 are venomous. There are four medically important snakes – the Big Four. These are the Cobra (Naja spp.; total 4 species), Russell’s Viper (Daboia russelii russelii), Common Krait (Bungarus caeruleus) and Saw-scaled Viper (Echis carinatus), which cause the highest fatalities in India. Approximately 10,000-50,000 people die of snakebite in India annually, which is probably the highest in the world.
Snakebites – where, when and how do they occur?
Snakebites largely occur in rural areas and is an occupational hazard; farmers being the most at risk. Farmers typically walk barefoot along the hedgerows and paddy fields, during dawn and dusk – the peak periods of snake activity. Snakebites are common during the rainy season and especially during floods, when they are flushed out of their underground burrows. Most snakebites occur as a result of ignorance about snake habits and habitats. For example, in rural areas, where snakes are prevalent, it is unwise to sleep on the floor. Bites by snakes, especially the common krait usually occur as a result of sleeping on the floor at night. This snake also has the habit of curling-up inside boots, and therefore, it is important to check boots before putting them on. Cobras are wide-ranging hunters, are very active and come in search of food such as rodents, frogs and toads in the vicinity of human dwellings. This leads to frequent encounters with humans. Russell’s vipers are stealthy hunters and are commonly found under bushes lining the fields. Saw-scaled vipers are found in dry, rocky and desert terrains and are also responsible for a large number of fatalities.
What to do (and not do) if a snake bites?
A venomous snakebite is a medical emergency. First aid should be short, simple and quick. Not much time should be wasted for it. The victim should be immediately transferred to a health facility where anti-snake venom (ASV) is available. Therefore, it is imperative that you should know what to do (and not do) when a snake bites.
• Reassure the victim. This is essential, as panic can aggravate the condition of a snakebite victim, especially if the bite is by a venomous snake. It should be remembered that approximately 70% of snakebites are by non-venomous snakes. Even in case of venomous snakebites, only 50% show signs of envenomation, as the snake often fails to inject the venom. This occurs in case of “scratch bites”, when the snake fails to get a good “bite” of the victim, and just scratches the surface of the skin. Sometimes, “dry bites” can occur, when the snake has already used-up all its venom by recently feeding on a prey. Thus, its venom glands are empty at the time of the bite.
• Wash the bitten area with soap and water. If you have access to soap and water, wash the bitten area, avoiding rubbing too much. The teeth and mouth of the snake have a rich microbial flora, and these can cause serious infections. Therefore, washing the area will help to reduce chances of spread of infection.
• Immobilize the limb. It is to be noted that in India, about 75% of snakebites occur on the legs, below the level of the knee. However, the hands and arms can also be bitten, especially if the bite occurs due to sleeping on the floor. Where ever the bite, the idea is to prevent the spread of the venom as much as possible. If the lower limb is involved, immobilize it as for a fracture, by using a splint and a bandage, or a clean cloth. Do not use too much pressure. It shouldn’t be too tight – at least a finger should be able to pass underneath it without difficulty. If the upper limb is involved, use a sling made from a bandage or a piece of cloth to restrict movement.
• Take a photo of the snake. Nowadays, most mobile phones are equipped with cameras. If the snake is still in the vicinity, try to take a quick photo, but be at a safe distance! Use a zoom if you have one. A photo of the incriminating snake will help in identification (whether it is venomous or non-venomous) and to correlate with clinical diagnosis once you reach a health facility. But don’t waste your time in trying to take a photo if the snake is not nearby. Getting the victim to hospital is your first priority.
• Take the victim to hospital quickly! Carry the patient, preferably on a stretcher in order to keep the bitten limb immobile as much as possible. Take the shortest route and take any type of vehicle that is available.
• Look out for the following signs so that you can tell the doctor at the hospital:
• Severe pain and swelling of the bitten limb.
• Non-stop bleeding from the bite site.
• Bleeding from gums, nose, and blood tinged sputum.
• Vomiting (with or without blood).
• Drooping eye lids.
• Drowsiness and intense desire to sleep. Don’t let the victim
• Difficulty breathing, speaking or swallowing.
• Don’t waste time.
• Don’t give the victim any sedatives. Pain killers can be given only if the pain is unbearable, which only occurs in case of venomous snakebites.
• Don’t use a tourniquet. Based on current scientific evidence, tourniquets are no longer recommended as they can do more harm than good. A tourniquet, especially if tied too tightly (which is usually the case) causes the venom to become concentrated locally, thereby leading to rapid tissue destruction near the bite site. Also, upon release of the tourniquet e.g. after reaching the hospital, there is a rapid release of venom that spreads rapidly causing systemic envenomation.
• Don’t attempt to suck out the venom with your mouth. This can harm you, especially if you happen to have a cut or ulcer in your mouth or a stomach ulcer.
• Don’t make any incision at the bitten site to squeeze out the venom. This is particularly dangerous in case of viper bites, which causes non-clotting blood. In such instances, the patient could bleed to death.
• Don’t use any suction device to suck out the venom. The use of such types of devices is highly controversial and not supported by hard scientific evidence.
• Don’t rub the bite site with ice.
• Don’t apply any ointments or chemicals on the bite site.
• Don’t go to a faith healers or seek traditional remedies.
• REMEMBER: Only ASV can save the life of a victim who has been seriously envenomed!
Once you reach the hospital…
Once you’ve taken the victim to the hospital, your job is essentially done. You’ve done all that you can do within your capacity. Leave the rest in the capable hands of the doctors, who are trained in administering ASV and managing other complications that may arise.
How can you avoid snakebites?
• If you encounter a snake, try to avoid it instead of confronting it and trying to kill it.
• Avoid venturing outdoors at night. Always carry a torch. Always keep your feet and legs covered.
• Do not sleep on the floor, especially in rural areas.
• Do not reach into a pile of coal or firewood, without being absolutely sure that there’s no snake inside. Always use a torch and a stick to probe the area first.
• Snakes are not as ferocious or dangerous as we generally accuse them to be.
• Like us humans, snakes too have every right to live on the Earth.
• Snakebite incidents occur because humans are increasingly encroaching on their territory.
• Snakes are necessary to maintain the ecological balance.
• Snakes eat rats that destroy our paddy crops. Therefore, snakes are good for our economy too.
• We just need to be more alert and cautious, and be aware of the habits and habitats of snakes in order to avoid unnecessary snakebite incidents.