It's not a freaking spider bite

Over at White Coat Underground, Pal has the post that I've been meaning to write. Earlier this summer, a family member posted on Facebook that a friend of her daughter was nursing a "nasty spider bite" that she got while camping in Michigan. Her post claimed it was a Brown Recluse bite. Being my usually buttinski self, I posted and told her that it was really, really unlikely to be a brown recluse bite, and that the friend-of-the-daughter-of-the-relative should hie thee to her physician and get the "bite" checked out. I told her that rather than a spider bite, it could be a Staph infection and may require antibiotics.

Now, I should note that few people in my family really "get" just what it is that I do, and even fewer of them realize that I spend my days researching bacterial infections, and that Staph in particular is my specialty. So I didn't take it personally when she pooh-poohed my suggestion and told me I had no idea what I was talking about, and that FOTDOTR's doctor had already seen the bite and proclaimed it to be due to a brown recluse. Okay, whatever, northern Michigan is completely the wrong place to get a bite from one of these critters and many research papers say the same thing--that "spider bites" usually aren't bites at all. I pointed this out (and linked some Google images of supposed spider bites in comparison to Staph infection images) and then left the conversation.

A day later, relative posted an update in the thread--FOTDOTR ended up going back to the doctor as the "bite" was getting worse. As I suspected, she had now officially been diagnosed with a staph infection--and yet they were still trying to determine "what kind of spider bit her." A few hours later, relative asked "What is MRSA? FOTDOTR was just diagnosed with that from the spider bite."

This is when I started pulling out my hair, since I'd linked info about MRSA several days prior by this point. There was no spider bite, damn it!

Anyway, FOTDOTR got treatment (though relative probably still believes it's from a spider bite) and I know at least a few people on the thread now may at least think "staph" when someone says "spider bite"--so overall, a good ending.

Pal notes:

Despite this widespread belief, most "spider bites" in my part of the country [Michigan, ahem--TS] aren't caused by spiders, and probably aren't bites at all. (The feared "brown recluse" does not live naturally in my part of the country, although importations have been reported. They do not generally survive through the winter.) The distinction is important for a few reasons. First, many of us are guilty of wanton arachnicide propelled by our unwarranted fears. Second, many "bites" are probably bacterial infections and should be treated properly. Finally, there's my own bias that we shouldn't assume things that aren't so.


More like this

Brava (and PAL too). You would not believe how many times I have had this exact conversation. Well, actually, OK, you probably would...

Indeed. I have my own little rant on the subject near the end of this article. The only reason I can figure for spiders getting blamed for so many of these skin lesions, is that people see a skin lesion, and jump to the conclusion that because it is small, circular, and red, it must be a bite. They then bound ahead to the assumption that they must have been bitten while sleeping, so they check in the bedroom and find spiders. Which they immediately blame.

For the record, I have captured, poked, prodded, and otherwise harassed a lot of spiders of many different species over the years while trying to get pictures. And not one of them has ever bitten me, or even shown any interest in trying. Not *one*. *Ever*. I am therefore *very* skeptical of people who claim spider bites unless they actually saw the spider do it.


I managed to harass a jumping spider into biting me once. It felt like a brief sharp pinch. However, there was no persistant welt or redness. And I agree. I am highly dubious of claims of spider bites. It's not as if a spider could possibly feed off a human. (Unlike the very many insects - and microbes - that do exactly that.

I have the same reaction when people tell me they killed a water moccasin or a copperhead in their back yard. Most of the time, they've merely killed some unfortunate nonvenomous snake.

iiiinteresting. Now I'm going through the various spots-on-skin things I've had over the years and wondering how many were actually bites of any type of critter at all. There's really only one time that I was fairly sure it was a spider - three marks in an uneven line that were "speckle-y" and itched like crazy for a couple of days. The spider caught in the blanket nearby made it seem like a good indicator, but that was years ago and I've never had anything similar again. And, now I think I could have been entirely wrong. Made for a good story to creep out my friends though.

Being bitten by things is annoying, and people are quite often afraid of spiders. Maybe they just seem like a convenient target for the blame. The idea that scary things can get you without your knowledge tends to kick in people's imagination. (and, in the case of your friend, her doctor's imagination apparently) Personally, spiders bug me far, far less than mosquitoes. I'd love to have spider webs all around my house if it would result in fewer frickin' mosquitoes.

By kickabout (not verified) on 11 Aug 2011 #permalink

In my experience, spider bites are usually characterized by a row of bites. The spider takes a chomp, walks a few paces, then takes another. Fortunately, the only spiders that have tasted my flesh have been pretty innocuous. No worse than mosquito bites.
But yeah, I've been through crawlspaces teeming with black widows and never gotten a bite from them. I have a couple big, fat harvestmen in cobwebs in my kitchen, happily keeping down the summer influx of fruit flies. They are welcome in my space as long as they stay out of my bed.

Boy, does this hit home. Several years ago I purchased a classic car for restoration. It had been sitting in a garage for several years with all of the various parts inside the car. I had it towed home and stuck it in my garage and eventually did an inventory of just exactly what I had bought. Several days after this exercize I developed a small, circular red patch on my right elbow. Now mind you, I never saw a spider or felt anything like a bite, but combined with a low-grade fever and flu-like symptoms, my wife eventually brought me to the emergency room. By this time the red patch had spread almost all of the way down from my right elbow to the wrist. Every one of my family members was telling every one within earshot, "Brown Recluse!, Brown Recluse!!" Seeing as how this was Arizona, it made some sense, but I was never convinced. Anyhow, I spent 6 days in the hospital being pumped with antibiotics before the infection would clear. Now, thanks to your post, my mind is now clear that the cause was not due to an insect bite, but probably a staf infection unrelated to the car, insects, my wife (well, maybe her..) or my family.

By koyote_ken (not verified) on 11 Aug 2011 #permalink

I used to have a tarantula that was quite aggressive, and would have bitten me given the chance, but to the best of my knowledge I've never been bitten by a spider. I have woken up in the morning with a dead spider in the sheets, and remembered that something was tickling my legs at night. Poor thing must have wandered into my bed thinking it was a safe place to hide, only to be squished as I rolled around at night. It didn't bite me, or at least there was no noticeable effect if it did.

I also had a jumping spider in my truck while I was camping in it near Moab. It jumped from a pile of clothes to the ceiling in the truck when I moved, so I raised a stainless steel plate up underneath it, which it obligingly dropped onto, so I could then let it out.

And I definitely agree with kickabout that "spiders bug me far, far less than mosquitoes". Those nasty little things have bitten me thousands of times, and they do carry some pretty nasty diseases (West Nile virus up here, malaria and other horrible diseases elsewhere).


Peter Parker actually had a staph infection?

How would the victim get the MRSA infection? Just pricking herself on something and either having the Staph already on her skin or exposing the broken skin afterward? Or is it possible to get the MRSA infection without a break in the skin?

By Robert Thille (not verified) on 11 Aug 2011 #permalink

Robert, it is possible to get an infection even without broken skin, though they're much more commonly associated with pre-existing wounds.

I recently was bitten by a spider in my sleep. And if it wasn't a spider, I'm not so sure I want to know what it was. There were two puncture wounds that eventually ended up blistering and swelling something awful. It hurt a little bit, but the worst part was the intolerable itching. I don't know if that was a direct result of the bite or if my hyperactive immune system identified it as an allergen, but ugh....I'm glad it's gone now, save for a fading scar. It took about a month to go away and that was with keeping it very clean and in a healing environment.

The only spiders that I've seen around where I sleep are jumping spiders, orb weavers, and those long skinny spindly ones that like to hang out in basements (not sure what they're called). I know the orb weavers are pretty docile, but I've read that the varieties of the latter two can give nasty bites sometimes, though nothing requiring medical intervention except occasionally in vulnerable individuals (e.g. infants)

I was pretty surprised when researching my awful spider bite to find out what you just posted above though. It turns out all those painful "bites" on me throughout the years were probably not from spiders at all, though I do suspect some sort of insect for the majority.

When I tell people that say they have a spider bite that it's probably something else, they seem offended....

By Bethistopheles (not verified) on 11 Aug 2011 #permalink

The "spider bite" of Baltimore is even less likely to be a spider and we basically translate it straight into "skin-popping" for the chart.

I suspect that in some communities doctors call any small red, inflamed spot that won't heal a 'spider bite'. Far less likely to cause a panic than telling them it's MRSA that might, with a heaping help of bad luck, cause their limb to liquefy and fall off. Standard treatment for these 'spider bites' is the same as treating a MRSA infection. Minus the panic.

Back in the 60s people felt roughly the way they panicked when they heard the diagnosis of cancer. There were all sorts of euphemisms used to avoid telling people they had the big-C. A popular one was their having an 'abnormal growth'.

I was reading a blog dealing with field medicine in remote locations and the medic claimed the standard treatment for such things, because antibiotics are extremely hard to get, was to rig a dilute chlorine bleach drip to irrigate the area and keep it saturated until the infection clears. Once cleared standard wound management was started. He claimed it worked well as lion as the patient was otherwise healthy.

I'm no expert but assuming your standard festering third-world hole and a chronic shortage of hygiene and medicine it sounded like a plan. I realize you can't make medical calls but it would be great to hear what an expert on staph has to say about what strikes me as a unconventional treatment plan.

Tim: I believed I had spider bites for the reasons you claim plus one more -- when I got rid of the spiders behind my bed, the recurrent bites stopped cold. It's not a lock-solid case, but it does seem logical.

Those of you who reported multiple bites in the night that were intensely itchy thereafter were bitten by the dread "kissing bug" Triatoma sanguisuga, a fit subject for the next blockbuster horror movie!

By bruce Morgan (not verified) on 13 Aug 2011 #permalink

In my twenties, I once put on a spring dress that had been hanging in my closet in Oregon all winter, and went to work. Shortly after I sat down at my desk, I felt a sharp sting on my thigh. I ran into the bathroom and lifted up my skirt and found a five inch circular bruise on my leg. I took off my dress and shook it, not finding any spider, and went back to work. Within an hour I started to feel a edgy and feverish and slightly dizzy. I worked all day and went home and never went to see a doctor. I felt sick for a day or two and then recovered. The bruise, however, lasted two or three months, gradually changing colors and finally clearing up. Based on the suddenness of the attack, and my feeling of having been poisoned, I am pretty sure it was a spider bite.

Better than waking up out of a sound sleep after a wasp sting. We commonly have Polistes wasps come in the house in the fall to overwinter and ending up crawling under the covers with you or dropping off the ceiling onto the bed in the middle of the night. Talk about jumping out of your skin!

I've spent years trying to convince friends that the red bump on them wasn't really a spider bite. Then my MIL got bit by something large enough to leave two visible fang marks on her leg and cause a huge nasty necrotizing reaction. It's the one and only time I've argued for a spider bite - she ended up going to the ER that day as the swelling spread more than 1 inch an hour. The doctor agreed, and guessed brown recluse. But we'll never know, because we never saw the beast.

By BlondMaggie (not verified) on 15 Aug 2011 #permalink

I wonder what nasties may be transmitted from the surface of the fangs by even non poisonous spiders.

By porchmonkey (not verified) on 03 Oct 2011 #permalink

I was bitten by a brown recluse while sleeping. After extensive research I found out that they carry the flesh eating disease and have migrated to almost all parts of the U.S. These spiders live for 7 years and are resistant to most pesticides.

By Suzanne Rosenorn (not verified) on 30 Nov 2011 #permalink

I know roaches can bite you and it looks like spider bites. I saw it on the show "Billy The Exterminator". There was a house that was so infested with roaches that there was a mouse that died and you could see the roaches eating it to the point where it was nothing but bones. They are especially dangerous to people with diabetes because most people don't feel them biting their legs, which get infected. Fleas bite too and sometimes the bites look like spider bites. All people have staph on their skin, it just takes a poke or scratch to open the skin and let the infection in.The spiders with the really long legs are what we call daddy longlegs and are not poisonious to humans because our skin is too thick for their fangs to puncture, but they are deadly to roaches and other bugs, so I don't mind them in the house.

By Minnie Spencer (not verified) on 12 Jan 2012 #permalink

I am quite confused by the ignorance of so many MI residents and doctors related to the diagnosis of brown recluse spider bites. I currently have a roommate that rents my basement. My home is only 17 yrs old and has a very nice finished basement area. The roommate is a veteran around 60 yrs old and not in the best of health. About one month ago, the roomate advised he had a spider bite on his rt forearm and it was very infected. He saw a doctor and was treated with antibiotics and it healed after a couple weeks. The roommate used a spider 'bomb' in the basement to kill any spiders hanging around. A couple days ago this roommate advised of another spider bite. The location was exactly the same as the first but on the lt forearm this time. Roommate was started on antibiotics again and was scheduled to return to VA in a couple days to have the 'bite' lanced. At his appt he was told he was definitely bit by a brown recluse spider. The doctor cut out a decent size area of his forearm and sent him home with more anti optics and bandages. When my roommate starting telling me about the extent of the infection I asked if it was MRSA. He of course said the doctors confirmed it was a brown recluse spider bite and pulled up pictures on the Internet to show him proof. I WAS SHOCKEd!! I can't imagine how a doctor could determine that a patient was bit by a brown recluse, in Michigan, twice in a month, in the same exact location but opposite sides of the body, without any signs of a spider, ever!!!! Now I am tiptoeing around my own house sanitizing everything!! How does a medical professional not know about the non-existence of brown recluse in MI and the rarity of a spider bite to begin with?? This roomate works in a bar and is always leaning his forearms on the bar as he stands. His skin is very thin and I can only surmise he had a tear in his skin and MRSA entered. How do I convince my roommate to address this further with his doctor? And how do I suggest he take extreme precautions not to spread the infection to the rest of the household without treating him like a leper?? Panic has taken me over!!

I had a deer tick removed on my upper left shoulder close to the neck within 8-12 hours, washed it, put iodine and anti-bacterial cream on it. This was on the 4th. On the 17th or 18th, about two weeks out, I had what appeared to be a bite surrounded by a very dark red rash, no bullseye, on my inner left thigh, which developed on the 19th through the 24th into light red splotches of rash all over my body. I froze the small deer tick and saved it for analysis. On my visit to the doctors they indicated that it probably was the deer tick bite that caused the rash, not a spider bite, and they took blood samples and put me on the antibiotic used for treating Lyme disease for 21 days. I am still on it and the rash is disappearing after the 3rd or 4th day so far. I have not received the report on the Lyme disease sample and will on July 1 - 27 days out from the tick bite; however, the test may no0t show positive until several weeks after the bite and this sample was taken almost 3 weeks - 20 days - after the bite.
I observed a puncture "bite" in the center of the dark red rash. Why could this have not been an insect? What else could cause a puncture mark that itched? None of the other light red rashes - some semi-circular with light "bullseyes" with no puncture marks itch. The nurse asked me if I ever had MRSA. I have not. Could this be a staph infection of some type coincidental with the tick or "spider" bite?

By James R Pitcher Jr (not verified) on 27 Jun 2014 #permalink

Okay... but every one of my "spider bites" is in pairs. Two bumps, not just one. And in various places -- my hand, my foot, my back, my stomach. All in pairs. Uneven pairs, like one fang had a lot more poison than the other, but still. I can't think of why staph or some other bacterial infection would consistently come in pairs like that, even if that would otherwise be a more likely explanation for the blisters that have formed a couple days after the itching and redness started.