Pest Control Alert
News to use from UGA Extension – www.ugaextension.org
Spiders are wrongly accused
Sharon Dowdy, News Editor with the
University of Georgia College of Agricultural and Environmental Sciences
A University of Georgia researcher
Association
says brown recluse spiders in Georgia
are being wrongly blamed for wounds
Events
they don't cause.
GA Pest Control
Association
"Most of the state of Georgia doesn't
even have brown recluse spiders,"
Certified Pest Control
said Nancy Hinkle, an entomologist
Operators Association of
with the UGA College of Agricultural
GA
and Environmental Sciences. "If the
spiders in the state caused all the
Georgia Mosquito
wounds that are reported as brown recluse bites, they would be some
Control Association
very busy spiders."
The Brown Recluse is not a Southerner
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Brown recluse spider isn’t
typically a Southerner
Spiders and other
Arachnids at UC Riverside
UGA Entomology
Department
UGA Homeowner Insect &
Weed Diagnostics Lab
From 2001 to 2007, Hinkle tracked verified findings of brown recluse
spiders in Georgia. The study was prompted by Hinkle's arrival from
California.
"When I first came to Georgia, I heard several people say they knew
someone who'd seen or been seriously wounded by a recluse," she said.
"I found that odd since the recluse is a Midwesterner, not a
Southerner."
The brown recluse is mostly brown but has a darker, violin-shaped
design where its legs attach. With its legs extended, it's only about the
size of a quarter.
Hinkle has received hundreds of spider samples from Georgians all
across the state. Rick Vetter from the University of California at
Riverside identifies the samples. He is the world's expert on brown
recluse spiders.
Only two out of 25 are Recluse Spiders
Lisa Ames with the UGA CAES Homeowner Insect and Weed Diagnostic
Laboratory in Griffin also collects spider samples submitted by
homeowners and pest control companies. In 2003, 2004 and 2005 she
received an average of 25 samples each year. Only two samples
annually were recluses.
Through 2007, the UGA scientists had collected only 14 verified brown
recluse spiders. And they had confirmed the spider in just 26 of
Georgia’s 159 counties, mostly in the northwest.
"Another reason for doing this study is to help the medical community
rule out brown recluse bites from portions of the state that don't have
the spiders," Hinkle said. "A diagnosis of a brown recluse bite in
Savannah is highly questionable.”
Most likely not spider bites
Hinkle hopes the study will educate Georgia's medical community and reduce the number of
erroneous recluse bite cases. A mark on the skin that looks like a spider bite could be
something much more serious.
She believes many assumed brown recluse bites could be methicillin-resistant Staphylococcus
aureus. MRSA is a type of staph infection that's resistant to antibiotics like penicillin, amoxicillin
and oxacillin. MRSA causes mild skin infections which result in pimples or boils. But it can also
cause more serious skin lesions or infect surgical wounds.
Wounds look similar
"Over the past five to 10 years, the number of MRSA cases has exploded," Hinkle said. A MRSA
infection can look like a brown recluse wound.
A brown recluse spider's bite often isn't the painful part of the experience. The spider's venom
destroys the tissue at the bite site. Several hours later, a blister-like sore appears and grows.
It can become as small as a pin to 8 inches across.
Almost all brown recluse bites heal nicely without medical intervention, Vetter said. And in spite
of all the horror stories, only 3 percent require skin grafts.
Incorrectly diagnosing MRSA as a spider bite, and vice versa, can result in a patient getting the
wrong therapy, Hinkle said. "The required treatment for a brown recluse bite is totally different
from the treatment needed for MRSA," she said. "Common antibiotics don't touch MRSA. And
you obviously wouldn't need to spray insecticides when you aren't dealing with a spider
problem."
Peaceful coexisters
Brown recluse spiders aren’t vicious and are not looking to bite people, Vetter said. A Kansas
family collected more than 2,000 brown recluses from their home in six months. "They've been
living there for eight years and still have shown no evidence of a single bite," he said. "People
tend to overreact and believe the worse."
To identify a brown recluse spider see: How to Identify and Misidentify a Brown Recluse Spider