Snake bites

India has the highest number of snakebite deaths in the world — an estimated 58,000 deaths per year, with hundreds of thousands more envenomings that leave people with permanent disability. Most bites happen in rural and agricultural areas, at night, during the monsoon season. Fast, correct first aid and urgent hospital transfer save lives.

The "Big Four" venomous snakes in India

Most medically significant bites in India come from these four species:

• Common Indian Cobra (Naja naja) — neurotoxic venom; causes paralysis, difficulty breathing
• Common Krait (Bungarus caeruleus) — highly neurotoxic; bites often occur while sleeping on the floor at night; pain is minimal, making early recognition hard
• Russell's Viper (Daboia russelii) — haemotoxic; causes bleeding, kidney failure, local tissue damage
• Saw-scaled Viper (Echis carinatus) — haemotoxic; causes widespread bleeding

Other medically relevant species include the hump-nosed pit viper (Malabar coast and Western Ghats), king cobra, and sea snakes.

Symptoms of snake bite

• Local: pain, swelling, blistering, bruising, bleeding from bite site, tissue damage at the bite
• Neurotoxic (cobra, krait): drooping eyelids (ptosis), difficulty swallowing or speaking, blurred vision, muscle weakness, difficulty breathing
• Haemotoxic (vipers): bleeding from gums, urine, stools, vomiting blood, bleeding at the bite site, bruising, low blood pressure, kidney failure
• Systemic: sweating, low blood pressure, rapid pulse, drowsiness, low urine output

Some bites are "dry" (no venom injected) — but you cannot tell at the scene. Treat every suspected venomous bite as an emergency until proven otherwise.

FIRST AID — what to do (and not do)

DO:

• Keep calm. Panic raises heart rate and spreads venom faster.
• Move away from the snake. Don't try to catch or kill it.
• Immobilise the bitten limb — use a splint as if for a fracture. Keep the limb at or below heart level.
• Remove rings, bangles, or tight clothing (swelling is likely)
• Get to a hospital that has anti-snake venom (ASV) as quickly as possible. Dial 112. Government district hospitals stock ASV.
• If possible, photograph the snake from a safe distance — helps identification. But don't delay transport to try to catch or photograph it.

DO NOT:

• Do NOT apply a tight tourniquet. It causes tissue damage and does not stop venom spread.
• Do NOT cut the wound or try to suck out venom.
• Do NOT apply ice, herbal remedies, cow dung, chilli powder, or "snake stones". These do not work and delay hospital care.
• Do NOT give alcohol or sedatives.
• Do NOT wait to see if symptoms develop — get to hospital immediately.

Hospital treatment

The definitive treatment is polyvalent anti-snake venom (ASV) — effective against the Big Four. ASV is given intravenously. Early administration saves lives and limbs. Supportive care may include ventilation (for neurotoxic bites), dialysis (for kidney failure from viper bites), blood products, and wound care.

Prevention

• Don't walk barefoot at night, especially in rural areas — wear boots and long trousers
• Use a torch when walking in the dark
• Sleep on a raised bed, not on the floor; use a bednet — many krait bites happen to people sleeping on the ground
• Keep homes and surroundings clean of food scraps and piles of debris that attract rodents (and therefore snakes)
• Seal cracks and holes in walls; cover drains
• Don't put bare hands into holes, woodpiles, or grain stores
• Farmers, harvesters, and field workers: wear boots and use a long stick to disturb grass ahead of you