Vetter repeated the experiment with the help of two other home owners, one in Missouri and one in Oklahoma. Although the numbers were nowhere near as large, both homes had dozens of brown recluses, and no one had ever been bitten in either of those houses either.
What it all shows, Vetter argues, is that it takes a bunch of brown recluses to pose much of a problem. And therein lies a peculiar fact concerning the spider's reputation. Many reports of brown recluse bites come from areas far beyond the spider's range, which is limited to the south-central Midwest from southeastern Nebraska down through Texas and along the southernmost edge of Ohio to parts of Georgia.
There are related species in the Southwest and elsewhere, but these are even more reclusive and pose much less of a problem for humans because they shy away from populated areas, Vetter says.
The occasional brown recluse that hitches a ride to somewhere outside its habitat poses no real threat, he adds, but all it takes is one citing to add to its legend.
Over the years Vetter has collected statistics showing that the reported number of bites is way out of proportion to the confirmed number of brown recluses found in areas outside its range. Some 478 brown recluse bites were reported in South Carolina in 1990 by physicians who answered his questionnaire, and 95 in Florida in 2000, and 120 in California in the past three years. Yet none of these areas have significant numbers of brown recluse spiders. Vetter confirmed fewer than 10 brown recluse specimens in California during the same period when 120 bites were reported.
"Without a doubt, virtually every single brown recluse bite diagnosis from a non-endemic recluse area is incorrect," he says.
It can be a tough call, he admits, because the wound left by a brown recluse can range from mild redness "to a rotting flesh wound." But a wrong diagnosis leads to the wrong treatment, and such deadly illnesses as lyme disease can look very similar to a recluse bite, he adds.
Vetter says 90 percent of all brown recluse bites heal by themselves without treatment, and only 3 percent require skin grafts.
"And there is not one proven brown recluse death yet in the United States," he insists. "There have been reported deaths, but none proven."
Bite Complaints Widespread
Still, the spider's legend continues to grow, and sometimes Vetter feels like he's shouting into the wind.
"If you have enough people saying the world is flat, people will believe it," he says. So the unsubstantiated reports keep coming into his office of brown recluses found in Canada and even Alaska, and it's impossible to prove that these warm-weather spiders aren't in either of those places.
"Can you prove there are no elephants running around in Alaska?" he asks. "If you go around and don't find any, is that because you are inept and don't know where to look? Did you look at night? Maybe they come out at night. So no matter what you do, you can't prove there are no elephants there."
Of course, Vetter admits he can?t rule out the possibility that a lone brown recluse might hitch a ride in someone?s luggage and end up biting someone thousands of miles away. He puts it this way:
"Yeah, like I'm male so I can have sex with a Playboy bunny. It's a possibility, but is it a likelihood? No."
Lee Dye’s column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.