Fort Bliss Monitor

Spider bites:
Brown recluse, Black widow can cause serious injury

1st Lt. Cletis Butler
WBAMC

Most spiders are shy and harmless to humans, and will not attempt to bite unless trapped or held. Spiders can be beneficial to humans as they feed on harmful insects and mites.

Wholesale destruction of spiders should be avoided, if possible. Venomous spiders inject offensive poisons into their victims. These are meant to disable or kill a victim so it can be eaten, and to soften or predigest the victim. Most spider bites occur at night when a spider passes over a sleeping victim. When discovered hours later, it is usually as a sore red bump.

The female black widow is only about 5/8 of an inch long, her shiny, jet-black body giving great contrast to the red hourglass marking on her round abdomen. She often eats the smaller male after mating, hence her name. Adult black widow spider males are harmless, about half the female’s size and usually have yellow and red bands with spots on their backs. Black widows live in wood piles, stone walls, under garbage cans, outside toilets and in similar hiding places.

The brown recluse, also known as the violin or fiddle-back spider because of the distinctive violin-shaped marking on its back, can also deliver a painless bite – or a bite that merely itches and burns at first. Later the surrounding tissue turns red or black and blue, and begins to disintegrate from the venom which is designed to digest the victim’s flesh. A crusted wound forms and, after the crust falls off, continues to deepen, forming a crater that may take months to heal. Brown recluse bites are often not diagnosed until considerable tissue damage has taken place, so it’s important to inform the doctor if you suspect a bite.

Seek medical attention if a bite is suspected from a black widow or brown recluse spider. Both spiders cause an ugly bite in a healthy adult. However, these spiders’ bites are particulary dangerous to the elderly, young or sick individuals.

Other spiders that can deliver painful bites include wolf and jumping spiders, wandering and garden spiders and tarantulas. Tarantulas are much feared and, in the case of some South American species, deservedly so. But the bites of the tarantulas that live in North America are no more serious than bee stings.

Tips to help prevent spider bites

• Indoors, collect and destroy spider webs, egg sacs and spiders with a strong suction vacuum cleaner and attachments to reach the necessary places.

• Use a dust mop, stiff broom and dustpan when needed to help discourage establishment.

• Move and dust often behind and under furniture, stored materials, wall hangings and corners of ceilings.

• Eliminate other household pests. Prey insects such as flies, ants and cockroaches attract spiders.

• Control excess moisture and humidity by keeping basements, crawl spaces, porches, etc., as dry as possible.

• Clean up woodpiles, trash, rocks and other debris outdoors – especially around the house foundation where spiders live.

• Use only flat-bottom garbage cans to eliminate resting areas for spiders.

• Use a hose with high-pressure water on the outside of the house to knock down and destroy webs, egg sacs and spiders.

• Use yellow or sodium-vapor light bulbs at outside entrances to reduce night-flying prey insects that may attract spiders.

When camping out, consider purchasing products pretreated with permethrin. Tents and the outside of sleeping bags may be treated with permethrin to kill spiders before they can bite. Mosquito nets also serve to protect you from night-biting spiders.

Pesticides should be used as the last line of defense. Spray attics, crawl spaces, cracks and crevices in molding, window and door trim, and undersides of tables, chairs and shelves.



www.bliss.army.mil	Published for the Fort Bliss/El Paso, Texas Community	October 21, 2004

<map name="boxmap-b4"> <area shape="rect" coords="0, 589, 120, 600" href="http://rcm.amazon.com/e/cm/privacy-policy.html?o=1" > <area coords="0,0,10000,10000" href="http://www.amazon.com/exec/obidos/redirect?tag=&creative=92501&camp=8117&link_code=dl1&path=subst/misc/amazon-cobrand-cc/v3/marketing-from-associates-step1.html/ref%3Db1_assoc_29" > </map>	Spider bites: Brown recluse, Black widow can cause serious injury 1st Lt. Cletis Butler WBAMC Most spiders are shy and harmless to humans, and will not attempt to bite unless trapped or held. Spiders can be beneficial to humans as they feed on harmful insects and mites. Wholesale destruction of spiders should be avoided, if possible. Venomous spiders inject offensive poisons into their victims. These are meant to disable or kill a victim so it can be eaten, and to soften or predigest the victim. Most spider bites occur at night when a spider passes over a sleeping victim. When discovered hours later, it is usually as a sore red bump. The female black widow is only about 5/8 of an inch long, her shiny, jet-black body giving great contrast to the red hourglass marking on her round abdomen. She often eats the smaller male after mating, hence her name. Adult black widow spider males are harmless, about half the female’s size and usually have yellow and red bands with spots on their backs. Black widows live in wood piles, stone walls, under garbage cans, outside toilets and in similar hiding places. The brown recluse, also known as the violin or fiddle-back spider because of the distinctive violin-shaped marking on its back, can also deliver a painless bite – or a bite that merely itches and burns at first. Later the surrounding tissue turns red or black and blue, and begins to disintegrate from the venom which is designed to digest the victim’s flesh. A crusted wound forms and, after the crust falls off, continues to deepen, forming a crater that may take months to heal. Brown recluse bites are often not diagnosed until considerable tissue damage has taken place, so it’s important to inform the doctor if you suspect a bite. Seek medical attention if a bite is suspected from a black widow or brown recluse spider. Both spiders cause an ugly bite in a healthy adult. However, these spiders’ bites are particulary dangerous to the elderly, young or sick individuals. Other spiders that can deliver painful bites include wolf and jumping spiders, wandering and garden spiders and tarantulas. Tarantulas are much feared and, in the case of some South American species, deservedly so. But the bites of the tarantulas that live in North America are no more serious than bee stings. Tips to help prevent spider bites • Indoors, collect and destroy spider webs, egg sacs and spiders with a strong suction vacuum cleaner and attachments to reach the necessary places. • Use a dust mop, stiff broom and dustpan when needed to help discourage establishment. • Move and dust often behind and under furniture, stored materials, wall hangings and corners of ceilings. • Eliminate other household pests. Prey insects such as flies, ants and cockroaches attract spiders. • Control excess moisture and humidity by keeping basements, crawl spaces, porches, etc., as dry as possible. • Clean up woodpiles, trash, rocks and other debris outdoors – especially around the house foundation where spiders live. • Use only flat-bottom garbage cans to eliminate resting areas for spiders. • Use a hose with high-pressure water on the outside of the house to knock down and destroy webs, egg sacs and spiders. • Use yellow or sodium-vapor light bulbs at outside entrances to reduce night-flying prey insects that may attract spiders. When camping out, consider purchasing products pretreated with permethrin. Tents and the outside of sleeping bags may be treated with permethrin to kill spiders before they can bite. Mosquito nets also serve to protect you from night-biting spiders. Pesticides should be used as the last line of defense. Spray attics, crawl spaces, cracks and crevices in molding, window and door trim, and undersides of tables, chairs and shelves.