INTRODUCTION:

Snakebite have been receiving increasing attention, one public health issue that causes significant levels of death and disability in the developing world has remained virtually unnoticed, receiving little to no attention on the global health agenda: snakebite. Snakes are endemic to every continent of the world except Antarctica, and many of these snakes possess venom strong enough to cause death or serious disability to humans^1,3,4. Though the exact number of snakebite is unknown, an estimated 5.4 million people are bitten each year with up to 2.7 million envenoming’s among that agricultural workers and children’s were mostly affected Snakebite, a wound resulting from penetration of the flesh by the fangs of a snake, especially a snake secreting venom through or near the fangs is called envenomation^3,7. Snakebite envenoming is a potentially fatal illness brought on by toxins in a venomous snake's bite. Some snake species have the ability to spit venom as a form of defense, which can result in envenoming if the venom gets into the eyes.². For millions of people around the world, the risk of being bitten by a snake is a constant worry as they go about their daily activities, such as walking to school, caring for gardens, managing livestock, fetching water, or even just using the restroom, where a careless step, a brief moment of inattention, or being in the wrong place at the wrong time can be fatal. Bites by venomous snakes can cause paralysis that may prevent breathing, bleeding disorders that can lead to a fatal hemorrhage, irreversible kidney failure and tissue damage that can cause permanent disability and limb amputation^3,9.

GLOBAL BURDEN OF SNAKEBITE:

The annual number of snakebites around the globe is estimated to be 1.2 – 5.5 million, of this 81 – 95% occur in tropical regions of south Asia. Between 81,410 and 137 880 people die every year, and there are roughly three times as many amputations and other types of permanent disabilities. In Asia, up to 2 million people are bitten by snakes annually, and in Africa, between 435 000 and 580 000 people are bitten³. 200,000 people every year are killed by snakebites worldwide, and the burden falls mainly on the world’s poorest, rural population. India has been dubbed the “snakebite capital of the world”. In India, it was reported that 1.2 million people had died from snakebite^4.Based on the survey conducted from 2000 to 2019, estimated that average death of 58,000 per year with nearly half of the victim aged 30 – 69 and over a quarter being children under 15 years of age^1,3,6.

Fig: 1 Global estimation of snakebite envenomation, (WHO, 2021)

Fig 2: Big Four Snakes of India

CLASSIFICATION OF SNAKES:

In India, there are more than 200 species of snakes, of which 60 are poisonous. The "Big Four" snakes—viper Russell's (Daboia Russelli), Indian cobra (Naja Naja), Indian krait (Bungarus Caeruleus), and saw-scaled viper (Echis Carmatus)—account for the vast majority of the country's fatalities and disabilities out of the country's more than 300 snake species, 60 of which are classified as venomous or mildly venomous^2,6,10. These big four snakes account for 90% of all venomous snakebite deaths in India. Within the Big Four, there are two main categories of snake: hemotoxic vipers (Russell’s and saw-scaled viper) and neurotoxic elapids (cobra and krait), whose bites cause substantially different sequelae. The pharmacological effects of snake venoms are classified into three main types, hemotoxic, neurotoxic, and cytotoxic^3,6,7.

SNAKE VENOM AND ITS COMPOSITION:

Snakes use the glandular secretion known as venom to paralyze and consume their prey. Additionally, it is employed as a defensive and survival tool. The primary duct travels from the main venom gland through the accessory gland and secondary duct, which exits into a fang sheath pocket, diverting venom into and through the fang. Venom is produced and stored in the main venom gland. The primary duct's loop allows the fang to move freely.^4,6. These characteristics are all bilateral. Snake venom, which contains zootoxins, is highly modified saliva that snakes use to digest and immobilize their prey as well as protect themselves from other dangers like predators. The injection system of the snake's modified fangs, which allow the venom to reach the target, delivers the venom produced by the venom gland apparatus.⁴

Fig 3: Glandular secretions of snake and its Composition

Snake venom is a lethal mixture which is composed of amino acids, nucleic acids, carbohydrates, lipids, proteins and peptides⁵. Snake venom contains protein at a dry weight of more than 90%. More than a hundred different proteins are found in each venom, including non-toxic proteins like nerve growth factor as well as enzymes, which make up 80–90% of viperid and 25-70% of elapid venoms respectively. These include enzymes that aid in digestion, hyaluronidase, and substances that either activate or inhibit bodily functions like kininogenase. The majority of venoms contain phosphomono and diesterases, 5 nucleotidase, DNAase, nucleosidase, phospholipase A, and peptidases in addition to l-amino acid oxidase^4,5.

PATHOGENESIS OF SNAKEBITE:

Serine proteases and other procoagulant enzymes, which are similar to thrombin or activate factor X, prothrombin, and other clotting factors, are present in the venoms of some Elapidae, Colubridae, and Viperidae. By causing fibrin to form in the bloodstream, these enzymes promote blood clotting. Contrarily, this process leads to incoagulable blood because the majority of the fibrin clot is immediately broken down by the body's own plasmin fibrinolytic system and, occasionally, within 30 minutes of the bite, the levels of clotting factors are so low (consumption coagulopathy) that the blood will not clot. Numerous anti-hemostatic substances are present in some venoms. For instance, the toxin-rich venom of the Russell's viper causes the activation of factors V, X, IX, and XIII, fibrinolysis, protein C, platelet aggregation, anticoagulation, and haemorrhage^4,5. Lecithinase is the most prevalent and thoroughly researched venom enzyme. It results in presynaptic neurotoxic activity, opiate-like sedative effects, and the auto-pharmacological release of histamine and anti-coagulation, damages mitochondria, red blood cells, leucocytes, platelets, peripheral nerve endings, skeletal muscle, and other membranes^4,6.

SIGNS AND SYMPTOMS OF SNAKEBITE:

Signs or symptoms of a snake bite may vary depending on the type of snake, but may include^6,7:

TYPE OF SNAKES	SIGNS AND SYMPTOMS
INDIAN COBRA	§ Two puncture wounds § Swelling and redness § Difficulty in breathing § Severe pain at the bite site § Vomiting and nausea § Blurred vision and drooping eyes § Numb face and limbs § Sweating and drooling of saliva
KRAIT	§ Often no visible bite marks § Severe abdominal pain, vomiting & sweating § Swollen tongue, drooling and slurred speech § Difficulty in breathing § Muscle weakness § Changes in blood pressure § Blurred vision & facial paralysis
RUSSELL’S VIPER	· Two fang mark clearly visible · Persistent bleeding from the bite site · Bleeding in eyes, nose and under tongue · Vomiting, nausea & abdominal pain · Swelling and growing wound · Discoloration of skin · Weakness from loss of blood
SAW- SCALED VIPER	· Blistering, swelling and growing wound · Excessive bleeding or blood clots · Vomiting and nausea · Blurred vision and difficulty in breathing · Burning pain at bite site

MANAGEMENT OF SNAKEBITE:

The most crucial action following a snake bite is to seek emergency medical attention as soon as you can. A qualified doctor will assess the patient to determine the best course of action. Sometimes a venomous snake bite is not immediately fatal.^3,6,7.

Anti-snake Venom Therapy:

Indian Polyvalent Anti Snake Venom Serum (AVS or ASV) is a unique solution to all type of venomous snakebite cases in India. It is called polyvalent as it can be used to treat many types of snakebites. Species specific “Monovalent” AVS is not available in India. Indian AVS is prepared from horse (mule or donkey) serum. The dose required depends on the clinical state. The dose requirement for viper bite is as follows^5,6:

a) Progressive local swelling, no systemic signs: 50 ml

b) Mild systemic symptoms + /- hematological & coagulation abnormalities: 50 - 100 ml

c) Severe poisoning, rapidly progressive or overt hemolysis or coagulopathy: 150 - 200 ml

Antivenom is injected into the person intravenously, and works by binding to and neutralizing venom enzymes. It cannot undo damage already caused by venom, so antivenom treatment should be sought as soon as possible. Modern antivenoms are usually polyvalent, making them effective against the venom of numerous snake species^3,6.

Criteria for Administration of ASV:

· ASV should be used with evidence of systemic envenomation or severe progressive local swelling.

· Essentially, systemic envenomation can be seen on the 20WBCT, in the presence of spontaneous bleeding after a viper bite, or by recognizing neurological impairment visually, such as ptosis.

· Evidence of coagulopathy- detected by 20WBCT or visible spontaneous abnormal bleeding from gums, bite sites, injection sites, etc.

· Ptosis, external ophthalmoplegia, paralysis of the muscles, and inability to raise the head are symptoms of neurotoxicity.^5,6, etc.

Indications for dialysis:

· Blood urea >130mg/dl (27mmol/L), BUN >100 mg/dl, senior creatinine >4 mg/dl (500mol/L), or signs of hypercatabolism such as a daily increase in blood urea >30mg/dl (BUN >15), senior creatinine >1 mg/dl, senior potassium >1mEq/L, and fall in bicarbonate >2mmol/L.

· Fluid overload leading to pulmonary edema

· Hyperkalemia (>7mmol/l (or hyperkalemic ECG changes)

· Unresponsive to conservative management

· Uremic complications – encephalopathy, pericarditis⁵

COMPLICATIONS OF SNAKE BITE:

Bites by venomous snakes can cause paralysis that may prevent breathing, bleeding disorders that can lead to a fatal haemorrhage, irreversible kidney failure and tissue damage that can cause permanent disability and limb amputation⁴. Permanent neurological injury from hypoxic encephalopathy is an important long-term effect of snake envenoming. Respiratory paralysis or cardiac arrest can both result in hypoxia and multi organ failure^5,6,7.

PREVENTION OF SNAKEBITE:

Some bites are nearly impossible to prevent. These include a snake that bites you when you accidentally step on it in the woods. But you can take steps to reduce your chances of being bitten by a snake. These include:

· Use a torch when walking at night

· Wear closed shoes or boots and watch your step in the bushes and in fields.

· Store firewood at safe distance from your home and be careful while handling it.

· Keep areas around home and building clear, and deter rats

· Supervise children while playing outside

· If you see a snake, don’t touch it. Give it a clear path to leave the area, or call the fire service (101) for help

· Avoid storing of too many things in the house that would enhance a snake to stay and hide^6,7.

CONCLUSION:

Dissemination of correct knowledge through health promotion is necessary to remove the misconceptions and to reduce the morbidity and mortality associated with snakebites. The availability and accessibility of these anti-venoms, along with raising awareness on primary prevention methods among communities and health workers, are the best ways to limit serious consequences and deaths from snakebite envenoming.

REFERENCES:

1. Chippaux JP. Snake-bites: appraisal of the global situation. Bull World Health Organ. 1998; 76 (5): 515– 24. PMID: 9868843.

2. Suraweera W, Warrell D, Whitaker R, Menon G, Rodrigues R, Fu SH, et al. Trends in snakebite deaths in India from 2000 to 2019 in a nationally representative mortality study. Jit M, Franco E, editors. eLife. 2020; 9: e54076. https://doi.org/10.7554/eLife.54076 PMID: 32633232.

3. WHO- Snakebite envenoming—A strategy for prevention and control. In: WHO [Internet]. [cited 18 May 2021]. http://www.who.int/snakebites/resources/9789241515641/en/.

4. Williams HF, Layfield HJ, Vallance T, Patel K, Bicknell AB, Trim SA, et al. The Urgent Need to Develop Novel Strategies for the Diagnosis and Treatment of Snakebites. Toxins (Basel). 2019; 11(6). Epub 2019/06/23. https://doi.org/10.3390/toxins11060363 PMID: 31226842; PubMed Central PMCID: PMC6628419.

5. Training Module For Management of Snake Bite Common Poisons. National Health Mission. Department of Health & Family Welfare Government of West Bengal (2018).

6. World Health Organization. “Guidelines for the management of snake-bites.” 2010.

7. Vaiyapuri, S., Vaiyapuri, R., Ashokan, R., Ramasamy, K., Nattamaisundar, K., Jeyaraj, A., Chandran, V., Gajjeraman, P., Baksh, M. F., Gibbins, J. M., & Hutchinson, E. G. (2013). Snakebite and Its Socio-Economic Impact on the Rural Population of Tamil Nadu, India. PLoS ONE, 8(11), e80090. https://doi.org/10.1371/journal.pone.0080090.

8. Kasturiratne A, Wickremasinghe AR, de Silva N, Gunawardena NK, Pathmeswaran A, Premaratna R, et al. The global burden of snakebite: a literature analysis and modelling based on regional estimates of envenoming and deaths. PLoS Med. 2008; 5(11):e218. Epub 2008/11/07. https://doi.org/10.1371/ journal.pmed.0050218 PMID: 18986210; PubMed Central PMCID: PMC2577696.

9. Nuchpraryoon I, Garner P (2000). "Interventions for preventing reactions to snake antivenom". The Cochrane Database of Systematic Reviews (2): CD002153 doi:10.1002/14651858.CD002153.

10. Waiddyanatha S, Silva A, Siribaddana S, Isbister GK. (2019) “Long-term Effects of Snake Envenoming. Toxins (Basel)” 11(4):193. doi: 10.3390/toxins11040193.

11. Adouani Badr, Elwali Abderrahman, Alaoui Hassan, Ait Elcadi Mina, Eljaoudi Rachid, Bousliman Yassir . Epidemiological Profile of Snakebites Cases recorded at the 3rd Military Hospital Laayoune Morocco between 2011 and 2017. Research J. Pharm. and Tech. 2018; 11(5): 1752-1756.

12. Liya John. Anti Snake Venom. Int. J. Nur. Edu. and Research. 2018; 6(4): 423-424.

13. Peyman Astaraki, Gholam Basati, Saber Abbaszadeh, Ghafar Ali Mahmoudi. A Review of medicinal plants used for snakebites and scorpion stings in Iran: A systematic review. Research J. Pharm. and Tech. 2020; 13(3):1565-1569.

14. Udayan Das, Shakti Ranjan Mohapatra. Behavioural Biases in Investment Decision Making: A research study on snakebite and house money effects on Indian individuals. Asian J. Management. 2017; 8(3):460-470.

Received on 25.11.2022 Modified on 22.03.2023

Int. J. Nur. Edu. and Research. 2023; 11(3):269-272.

DOI: 10.52711/2454-2660.2023.00061