The spider, according to "Dorland's Illustrated Medical Dictionary, 31st ed.," belongs to the species named arachnid. Characterized by a two-part body, the head and thorax section with eight legs and the abdomen or rear section, arachnids of many varieties live all over the world. The ones that exist in the United States are generally harmless to humans. Spiders serve as exterminators of pesty insects. Most bite with little consequence. However the notable exceptions--the black widow and the brown recluse--can cause terrible sickness and death.
Identification
Five species of black widow spiders live in North America. Black with an hourglass shaped body, the widow has two bright red triangular marks on its abdomen. The brown recluse spider resides in the southern and midwestern parts of the United States. Also referred to as the violin spider and the fiddle back spider, the brown recluse bears the shape of a violin on its back.
Black Widow Bite Symptoms
Ohio State University notes that the venom of the black widow spider travels through the bloodstream and causes pain when it attacks the nervous system. Initially, the bite may go unnoticed, although some victims report a stabbing pain. The bite site then reddens and swells. The pain travels to the abdomen and back as the venom continues to move through the body. This causes nausea, profuse sweating, tremors and trouble breathing, along with increases in blood pressure and body temperature. The symptoms typically ease after a few days and the bite rarely causes death.
Brown Recluse Bite Symptoms
The University of Kentucky notes that the symptoms of a brown recluse bite vary according to where the bite takes place. They range from no notice of the bite to feeling a slight sting. After a few hours, redness and swelling appear. The bluish recessed lesion has a blistered center. Redness surrounds the site. The lesion eats away at the surrounding tissue for a period of months before subsiding and leaving a deep scar. In rare cases, death occurs.
Black Widow Bite Treatment
An ice pack applied to the site of a black widow bite can ease the pain and swelling. Pain medication or muscle relaxants will relieve the most severe pain. The antivenin anti-venom helps young children and the elderly, the most vulnerable populations. According to the 2010 edition of "Current Medical Diagnosis and Treatment," antivenin carries a risk of hypersensitivity because it contains horse serum. Testing for sensitivity should precede the use of this treatment.
Brown Recluse Bite Treatment
Immediate treatment of the brown recluse bite helps abate its effects. This involves early excision of the venom, according to "Current Medical Diagnosis and Treatment." The bite of the brown recluse can lead to tissue death at the bite site, which spreads as the venom travels. Tissue death or necrosis involves the red blood cells. Killing these cells, called hemolysis, can and does lead to death in some cases. Corticosteroid medication slows or stops this process.
Prevention
Spiders love dark places and take up residence where they have the most privacy. Their living habits sometimes put them in contact with humans accidentally, as when they crawl into a shoe or under the bed covers. When a human steps into an occupied shoe or rolls over in bed onto the spider, it responds to the surprise skin contact with a bite. To avoid all spider bites, use some precautions: shake out your shoes before wearing them; keep dust ruffles from your bed off the floor so spiders have less access; don't leave clothes piled on the floor; inspect anything from outdoors before bringing it inside; and regularly rid your home of webs and egg clusters.
References
- "Current Medical Diagnosis and Treatment"; Stephen J. McPhee and Maxine A. Papadakis; 2010
- "Dorland's Illustrated Medical Dictionary, 31st ed."; Sanders Elsevier, publisher; 2007
- Orkin Pest Control: Brown Recluse Spider Bite Symptoms
- University of Kentucky College of Agriculture: Brown Recluse Spider
- Ohio State University: Black Widow Spider Fact Sheet
