Grow Youthful: How to Slow Your Aging and Enjoy Extraordinary Health
Grow Youthful: How to Slow Your Aging and Enjoy Extraordinary Health

Spider bite

Most spiders are harmless

Symptoms of spider bite

Potentially lethal spiders

Remedies / treatment for spider bite

References

Most spiders are harmless

There are about 40,000 known species of spiders, of which only 200 have serious, potentially lethal bites. (1) Most spider bites occur when someone unintentionally brushes against or touches a spider and gets a defensive bite. On rare occasions a spider may mistake a finger or other body part for prey, as if it were a caterpillar or other insect. Many spiders do not have mouthparts capable of penetrating human skin. Only the larger spiders have fangs long enough to penetrate human skin. Most spider bites are not even noticed. Of those that are noticed, 98% have no serious medical consequences.

Two types of spider bites are harmful and/or painful. Most common are those bites that inject sufficient harmful venom. The amount of venom injected with a bite can vary a lot, even with the same spider. The other cause is harmful infections, which occurs in less than 1% of bites.

Spider venom is usually neurotoxic - meaning containing chemicals which attack the nervous system. Different venoms from different spiders can act in different ways. Venomous bites can be painful, and in the worst cases can stop breathing and the heart. A very few spiders have a venom that is so toxic that a single bite can cause death.

Other spider venoms contain necrotic agents that damage and destroy cells. Usually necrotic venoms attack tissues surrounding the bite, but in a few cases they may affect other organs.

Symptoms of spider bite

Potentially lethal spiders

Neurotoxic

funnel web spider
Funnel web spider. Found on the east coast of Australia.


black widow spider / redback Japanese widow spider
Black widow spider. Various widow spiders are found on every continent except Antarctica. The single species occurring in Australia is commonly called the redback.


Brazialian wandering spider
Brazilian wandering spider (Banana spider). Found mainly in tropical South America.


mouse spider
Mouse spider. There are eleven known species. Ten are Australian, one is from Chile.


Necrotic

brown recluse spider recluse spider
Spiders with necrotic venom often come from the family Sicariidae, which includes both the recluse spiders (violin spiders, fiddlers or fiddlebacks) and the six-eyed sand spiders. Different species of recluse spiders are found in warmer climates worldwide. Six-eyed sand spiders are found in deserts and sandy places in southern Africa.

Remedies / treatment for spider bite

References

1. Diaz, James H. The global epidemiology, syndromic classification, management, and prevention of spider bites. 1 August 2004. American Journal of Tropical Medicine and Hygiene 71 (2): 239-250. PMID 15306718.