Snakebite

For other uses, see Snakebite (disambiguation).

Snakebite
A cobra bite on the foot of a girl in Thailand
SpecialtyEmergency medicine
SymptomsTwo puncture wounds, redness, swelling, severe pain at the area[1][2]
ComplicationsBleeding, kidney failure, severe allergic reaction, tissue death around the bite, breathing problems, amputation, envenomation[1][3]
CausesSnakes[1]
Risk factorsWorking outside with one's hands (farming, forestry, construction);[1][3] harassment;[4][5] drunkenness[6]
PreventionProtective footwear, avoiding areas where snakes live, not handling snakes[1]
TreatmentWashing the wound with soap and water, antivenom[1][7]
PrognosisDepends on type of snake[8]
FrequencyUp to 5 million a year[3]
Deaths94,000–125,000 per year[3]

A snakebite is an injury caused by the bite of a snake, especially a venomous snake.[9] A common sign of a bite from a venomous snake is the presence of two puncture wounds from the animal's fangs.[1] Sometimes venom injection from the bite may occur.[3] This may result in redness, swelling, and severe pain at the area, which may take up to an hour to appear.[1][2] Vomiting, blurred vision, tingling of the limbs, and sweating may result.[1][2] Most bites are on the hands, arms, or legs.[2][10] Fear following a bite is common with symptoms of a racing heart and feeling faint.[2] The venom may cause bleeding, kidney failure, a severe allergic reaction, tissue death around the bite, or breathing problems.[1][3] Bites may result in the loss of a limb or other chronic problems or even death.[11][3]

The outcome depends on the type of snake, the area of the body bitten, the amount of snake venom injected, the general health of the person bitten and whether or not anti-venom serum has been administered by a doctor in a timely manner.[11][8] Problems are often more severe in children than adults, due to their smaller size.[3][12][13] Allergic reactions to snake venom can further complicate outcomes and can include anaphylaxis, requiring additional treatment and in some cases resulting in death.[11]

Snakes bite both as a method of hunting, and as a means of protection.[14] Risk factors for bites include working outside with one's hands such as in farming, forestry, and construction.[1][3] Snakes commonly involved in envenomations include elapids (such as kraits, cobras and mambas), vipers, and sea snakes.[7] The majority of snake species do not have venom and kill their prey by constriction (squeezing them).[2] Venomous snakes can be found on every continent except Antarctica.[14] Determining the type of snake that caused a bite is often not possible.[7] The World Health Organization says snakebites are a "neglected public health issue in many tropical and subtropical countries",[13] and in 2017, the WHO categorized snakebite envenomation as a Neglected Tropical Disease (Category A). The WHO also estimates that between 4.5 and 5.4 million people are bitten each year, and of those figures 40–50% develop some kind of clinical illness as a result.[15] Furthermore, the death toll of such an injury could range between 80,000 and 130,000 people per year.[16][15] The purpose was to encourage research, expand accessibility of antivenoms, and improve snakebite management in "developing countries".[17]

Prevention of snake bites can involve wearing protective footwear, avoiding areas where snakes live, and not handling snakes.[1] Treatment partly depends on the type of snake.[1] Washing the wound with soap and water and holding the limb still is recommended.[1][7] Trying to suck out the venom, cutting the wound with a knife, or using a tourniquet is not recommended.[1] Antivenom is effective at preventing death from bites; however, antivenoms frequently have side effects.[3][18] The type of antivenom needed depends on the type of snake involved.[7] When the type of snake is unknown, antivenom is often given based on the types known to be in the area.[7] In some areas of the world, getting the right type of antivenom is difficult and this partly contributes to why they sometimes do not work.[3] An additional issue is the cost of these medications.[3] Antivenom has little effect on the area around the bite itself.[7] Supporting the person's breathing is sometimes also required.[7]

The number of venomous snakebites that occur each year may be as high as five million.[3] They result in about 2.5 million envenomations and 20,000 to 125,000 deaths.[3][14] The frequency and severity of bites vary greatly among different parts of the world.[14] They occur most commonly in Africa, Asia, and Latin America,[3] with rural areas more greatly affected.[3][13] Deaths are relatively rare in Australia, Europe and North America.[14][18][19] For example, in the United States, about seven to eight thousand people per year are bitten by venomous snakes (about one in 40 thousand people) and about five people die (about one death per 65 million people).[1]

  1. ^ a b c d e f g h i j k l m n o p "Venomous Snakes". U.S. National Institute for Occupational Safety and Health. 24 February 2012. Archived from the original on 29 April 2015. Retrieved 19 May 2015.
  2. ^ a b c d e f Gold BS, Dart RC, Barish RA (August 2002). "Bites of venomous snakes". The New England Journal of Medicine. 347 (5): 347–356. doi:10.1056/NEJMra013477. PMID 12151473.
  3. ^ a b c d e f g h i j k l m n o p "Animal bites: Fact sheet N°373". World Health Organization. February 2015. Archived from the original on 4 May 2015. Retrieved 19 May 2015.
  4. ^ "Eldorado - Outdoor Safety & Ethics".
  5. ^ "What to do if you encounter a rattlesnake".
  6. ^ "Alcohol and Snake Bites – Reptiles Magazine". December 2011.
  7. ^ a b c d e f g h "Neglected tropical diseases: Snakebite". World Health Organization. Archived from the original on 30 September 2015. Retrieved 19 May 2015.
  8. ^ a b Marx JA (2010). Rosen's emergency medicine: concepts and clinical practice (7 ed.). Philadelphia: Mosby/Elsevier. p. 746. ISBN 978-0-323-05472-0. Archived from the original on 21 May 2015.
  9. ^ "Definition of Snakebite". www.merriam-webster.com. Retrieved 17 June 2019.
  10. ^ Daley BJ, Torres J (June 2014). "Venomous snakebites". Journal of Emergency Medical Services. 39 (6): 58–62. PMID 25109149.
  11. ^ a b c Eske J, Biggers A (14 December 2018). "How to identify and treat snake bites". Medical News Today. Healthline Media UK Ltd. Retrieved 4 May 2022.
  12. ^ Peden MM (2008). World Report on Child Injury Prevention. World Health Organization. p. 128. ISBN 978-92-4-156357-4. Archived from the original on 2 February 2017.
  13. ^ a b c "Snake antivenoms: Fact sheet N°337". World Health Organization. February 2015. Archived from the original on 18 April 2017. Retrieved 16 May 2017.
  14. ^ a b c d e Kasturiratne A, Wickremasinghe AR, de Silva N, Gunawardena NK, Pathmeswaran A, Premaratna R, et al. (November 2008). "The global burden of snakebite: a literature analysis and modelling based on regional estimates of envenoming and deaths". PLOS Medicine. 5 (11): e218. doi:10.1371/journal.pmed.0050218. PMC 2577696. PMID 18986210.
  15. ^ a b Langley R, Haskell MG, Hareza D, King K (October 2020). "Fatal and Nonfatal Snakebite Injuries Reported in the United States". Southern Medical Journal. 113 (10): 514–519. doi:10.14423/SMJ.0000000000001156. PMID 33005969. S2CID 222070778.
  16. ^ World Health Organization. Prevalence of snakebite envenoming. [https://web.archive.org/web/20170922113845/http://www.who.int/snakebites/epidemiology/en/ ]. Accessed April 15, 2019
  17. ^ "WHO | Snakebite envenomation turns again into a neglected tropical disease!". WHO. Archived from the original on 22 September 2017.
  18. ^ a b Gutiérrez JM, Lomonte B, León G, Rucavado A, Chaves F, Angulo Y (2007). "Trends in snakebite envenomation therapy: scientific, technological and public health considerations". Current Pharmaceutical Design. 13 (28): 2935–2950. doi:10.2174/138161207782023784. PMID 17979738.
  19. ^ Chippaux JP (1998). "Snake-bites: appraisal of the global situation". Bulletin of the World Health Organization. 76 (5): 515–524. PMC 2305789. PMID 9868843.