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Spider Bites

How to Identify and Treat Spider Bites

Dark, damp, still places are ideal homes for all sorts of spiders. They are commonly found at SLAC in tunnels, darkened cabinets, modules, nooks, and crannies. The majority of bites occur between April and October.

Most spiders are harmless and most spider bites are small nuisances that do not need treatment. However, the female black widow spider (Latrodectus mactans), whose shiny black body has a red hourglass-shaped mark on the abdomen, can bite and cause a tender swelling followed by illness.

Please note the following possible reactions:

  • Typically, a bite from a female black widow causes a reaction similar to that of a mosquito bite except that it is larger, heals more slowly, and is more tender than itchy. If you keep these bites clean with hot soapy water and don't scratch or pick them, they will heal within two weeks.
  • Rarely, a black widow bite will result in a severe, post-bite illness characterized by abdominal and generalized muscle cramps, sweating, and nervous hyperactivity. These symptoms require prompt treatment. If you notice you are developing these symptoms shortly after being bitten, go directly to Occupational Health Center (x2281) or your own doctor. (Remember to tell the doctor that your symptoms followed a spider bite.)

As a preventive measure while you are working in a likely spider habitat, attempt to limit your available skin surface by wearing a tee shirt under a long-sleeved shirt and tucking long trouser legs into your socks.

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