Why Are My Mosquito Bites Only Behind My Knee?

[DaveC426913]

Sunday night I sat outside for three hours. I was wearing long pants and a sweatshirt and there was a mosquito candle on the table in front of me. There are confirmed mosquitos still in our yard, though I did not swat any away that night.

A few hours after coming in, I found I had about 9 mosquito bites, all of them in the crease of the back of my left knee. All within a two inch area. I got no other bites anywhere on me.

If they are indeed mosquito bites, they would have had to ignore all the exposed skin on my head/neck/face/throat and hands, and instead fly up my one pant leg, land at my knee and bite me nine times.

I'm trying to find alternate cuplrits to explain the bites. Spiders or ants, on the edge of the chair, maybe biting through my pants? No.

I thought maybe chiggers, that tend to bite many times near creases and stuff.

But these are exactly like mosquito bites (though big, tightly grouped and quite itchy).

I have a pic but that won't tell you much. They look and feel like mosquito bites.

Ideas?

 

[Monique]

I had the same situation in Japan, I was covered in DEET and was wearing long pants. Still some bug managed to bite me just below the knee in the morning hours. It didn't appear to be mosquito bites, because the kind of skin reaction was different than usual. I was, and still am, puzzled by the origin.

I hate mosquitos. The fall has already set in two months ago, but I still find mosquitos in my room every night. All I need to do is wake up (usually around 3 am) and find a mosquito camping out above my pillow, which I then catch in a glass and get rid of. The same ritual every night. Today I was stalked by another mosquito, but now in the train. It didn't want to leave my side, but I was fortunate to not get bitten. If you don't want to bitten by bugs, you just need to hang out with me: I'm a better bait.

 

[lisab]

Fleas, maybe?

I think I'll go with spider, though. One may have crawled up your pants...*shiver*.

Oh great, now I have the heebie-jeebies.

 

[Monique]

I often get bitten by fleas as well (in public places, I don't own pets) They are very easy to recognize though, I always catch them while biting. It is a good candidate for Dave though, fleas do like to bite in the same spot multiple times.

 

[DaveC426913]

Hmm. Fleas.

Well, the grouping fits.

Though flea bites are usually tiny and red, aren't they?

 

[turbo]

Could be the mites that are responsible for sarcoptic mange in dogs. VERY itchy bumps.

 

[Monique]

Looks like flea bites to me, they usually become red after a day. The swelling is quite strong, it could have been a different kind that you have a stronger reaction to than usual?

 

[Evo]

How far are you from the bed bug plague that's taking over NY Dave?

 

[turbo]

Dave, dog mites love to bite in creases where the skin is very thin. You won't notice them while biting - only afterward when your immune system kicks in.

 

[lisab]

Dave, dog mites love to bite in creases where the skin is very thin. You won't notice them while biting - only afterward when your immune system kicks in.

Dog mite gives man nine bites!

 

[Dembadon]

I think it is more likely that they were caused by something that was already in your pants before you put them on, rather than by something that somehow made its way up your pants to that specific spot on/behind your knee.

 

[Evo]

I think it is more likely that they were caused by something that was already in your pants before you put them on, rather than by something that somehow made its way up your pants to that specific spot on/behind your knee.

We've had an outbreak of spiders here. They've sprayed all around the outside of the apartments and around the windows, so all of the spiders have come inside for safety. I regularly turn my clothes inside out and shake and thoroughly check my shoes before getting dressed now. I've never seen so many different spiders.

I think it's a flea or a spider Dave.

 

[Dembadon]

In https://www.physicsforums.com/showthread.php?t=262090" thread, which was created around the same time of the year (fall) about two years ago, you had a similar episode. Chemisttree thought they might be chiggers (post #15). Could this be a repeat occurrence? Were you able to verify if they were chiggers or not?

 

[Norman]

The spider bites I have always seen had a crater-like center. I don't know if that is always the case, but I have seen a fair number**.

The bites sure look like mosquitos to me. I have never seen human flea bites, so I can't say much there.


**when we were kids my brother had a monster wolf spider snacking on him for s few nights until we lured the bastard out and killed it. He probably had 50 bites on him in the end.

 

[lisab]

The spider bites I have always seen had a crater-like center. I don't know if that is always the case, but I have seen a fair number**.

The bites sure look like mosquitos to me. I have never seen human flea bites, so I can't say much there.


**when we were kids my brother had a monster wolf spider snacking on him for s few nights until we lured the bastard out and killed it. He probably had 50 bites on him in the end.

Ouch, that's a bad place to get even one bite.

 

[lisab]

In https://www.physicsforums.com/showthread.php?t=262090" thread, which was created around the same time of the year (fall) about two years ago, you had a similar episode. Chemisttree thought they might be chiggers (post #15). Could this be a repeat occurrence? Were you able to verify if they were chiggers or not?

Wow, I'm impressed! You have a memory like a steel trap!

 

[Evo]

In https://www.physicsforums.com/showthread.php?t=262090" thread, which was created around the same time of the year (fall) about two years ago, you had a similar episode. Chemisttree thought they might be chiggers (post #15). Could this be a repeat occurrence? Were you able to verify if they were chiggers or not?

I had forgotten about his attack last year.

 

[Dembadon]

Wow, I'm impressed! You have a memory like a steel trap!

Actually, I noticed it in the 'similar threads' area at the bottom of this thread. I was even more surprised when I saw the seasonal correlation.

I wish my memory was that good!

 

[DaveC426913]

How far are you from the bed bug plague that's taking over NY Dave?

Don't think so.

I think it is more likely that they were caused by something that was already in your pants before you put them on, rather than by something that somehow made its way up your pants to that specific spot on/behind your knee.

Well, then they waited around for 12 hours before biting.

In https://www.physicsforums.com/showthread.php?t=262090" thread, which was created around the same time of the year (fall) about two years ago, you had a similar episode. Chemisttree thought they might be chiggers (post #15). Could this be a repeat occurrence? Were you able to verify if they were chiggers or not?

Wow. Even I didn't remember that. Two years ago next week.


I have remembered that, an hour before going in, I chased a spider out of the tent over my head and it dropped on the ground. Shortly after that, it zoomed across my belly while I was stting and I had to shake it off. So, spider on the ground right at my feet, hanging from me by silk...

 

[JaredJames]

http://www.patient.co.uk/health/Physical-Urticarias.htm

Look for the section: Cholinergic urticaria

Heat bumps? Look like bites and are really itchy. Look exactly like the photo you gave, I get them sometimes.

Home remedy (apparently, I just let them go):
http://www.ehow.co.uk/way_5591552_home-remedy-heat-bumps.html

 

[DaveC426913]

http://www.patient.co.uk/health/Physical-Urticarias.htm

Look for the section: Cholinergic urticaria

Heat bumps? Look like bites and are really itchy. Look exactly like the photo you gave, I get them sometimes.

Home remedy (apparently, I just let them go):
http://www.ehow.co.uk/way_5591552_home-remedy-heat-bumps.html

Well I get heat rashes; I don't think this is from heat (it was quite chilly out - did I mention I was actually wearing something that had long sleeves? Before December?)

 

[JaredJames]

Well I get heat rashes; I don't think this is from heat (it was quite chilly out - did I mention I was actually wearing something that had long sleeves? Before December?)

Yeah but sweat can cause it. It is under the knee after all.

But sometimes they appear rather randomly on my skin. Itch for about ten minutes and then disappear.

 

[DaveC426913]

Yeah but sweat can cause it. It is under the knee after all.

But sometimes they appear rather randomly on my skin.

Yeah. I'm pretty familiar with how my bod reacts to heat.

Itch for about ten minutes and then disappear.

These have been nasty, nasty itchy for two days. Like, enough for me to actually actually apply stuff on them (and I hate applying stuff). I apply it about every four hours.

 

[JaredJames]

These have been nasty, nasty itchy for two days. Like, enough for me to actually actually apply stuff on them (and I hate applying stuff). I apply it about every four hours.

Sounds nasty.

 

[Dembadon]

I think it is more likely that they were caused by something that was already in your pants before you put them on, rather than by something that somehow made its way up your pants to that specific spot on/behind your knee.

Well, then they waited around for 12 hours before biting.

Another unlikely scenario. I made the poor assumption that you put on the pants just before going outside.

A few hours after coming in ...

The following quote is from http://www.medicinenet.com/chiggers_bites/page2.htm" (don't know how reliable this website is).

A chigger bite itself is not noticeable. After the chigger has begun to inject digestive enzymes into the skin (usually after about 1-3 hours), symptoms typically begin.

Hardly a case-closing discovery, but it fits the time-frame nonetheless.

How cold was it? The site claims that "[c]higgers do not bite at colder temperatures (below 60 F or 15.5 C)." I'd guess it was colder than that if you were wearing pants and a sweatshirt, but people's comfort-level thresholds for air temperatures are different, so I figured I'd ask. Another observation that could rule out chiggers is that you were appropriately dressed, as the site suggests "[l]ong pants and long-sleeved shirts as well as thick socks and high shoes or boots can help prevent infestation. Pants legs should be tucked into shoes or boots if possible."

Perhaps it was the spider. Can you describe your arachnid admirer?

 

[wolram]

Ouch, that's a bad place to get even one bite.

 

[DaveC426913]

How cold was it? The site claims that "[c]higgers do not bite at colder temperatures (below 60 F or 15.5 C)." I'd guess it was colder than that if you were wearing pants and a sweatshirt, but people's comfort-level thresholds for air temperatures are different, so I figured I'd ask.

It was probly about 15C. Simply sitting for 2-3 hours can require a long-sleeve.

Another observation that could rule out chiggers is that you were appropriately dressed, as the site suggests "[l]ong pants and long-sleeved shirts as well as thick socks and high shoes or boots can help prevent infestation. Pants legs should be tucked into shoes or boots if possible."

No, just normal late season* clothes. (*which means actually wearing socks)

Perhaps it was the spider. Can you describe your arachnid admirer?

Common garden spider. Get em around here by the buttload.

 

[turbo]

Common garden spider. Get em around here by the buttload.

That's NOT where you're supposed to keep them, you know.

 

[rhody]

Dave,

Without knowing exactly what got to you, you have to admit one thing, your immune system had an abnormally aggressive reaction (and possibly time delayed reaction) to it, right ? Based on that information, assuming you have never had welts like this in the past (and knew where they came from), would be be reasonable to suggest that whatever bit you multiple times was "brand new to you immune system" ? With that many welts, did you feel the first one ? I bet once your immune system went postal, you did. Really strange that you didn't feel them as they happened. From the picture you posted, it looks like there is some kind of delayed reaction going on as well. Sorry I couldn't pin this down for you. They, the welts that is, didn't burst open and weep, did they ?

Rhody...

 

[DaveC426913]

Dave,

Without knowing exactly what got to you, you have to admit one thing, your immune system had an abnormally aggressive reaction (and possibly time delayed reaction) to it, right ? Based on that information, assuming you have never had welts like this in the past (and knew where they came from), would be be reasonable to suggest that whatever bit you multiple times was "brand new to you immune system" ? With that many welts, did you feel the first one ? I bet once your immune system went postal, you did. Really strange that you didn't feel them as they happened. From the picture you posted, it looks like there is some kind of delayed reaction going on as well. Sorry I couldn't pin this down for you. They, the welts that is, didn't burst open and weep, did they ?

Rhody...

Are you sure you're not overthinking it?

Sure, they're itchy as heck, but I think that's because there's so many. The nerves are being terrorized. And it's in a spot that is sensitive and continually stimulated.

But when all is said and done, they're exactly like mosquito bites.

The only thing uncharacteristic is their location and grouping density (sheer number in a small area), which is very unlike mosquitoes.

 

[DaveC426913]

Update:

Have not been outside at all tonight, and am not wearing the same pants as before. Have been sitting here on the couch in the living room for the last few hours, minding my own business.

I now have a small grouping of bites on my right thigh.

As I now recall, in the 2008 incident, the couch was the prime suspect.

 

[Proton Soup]

Update:

Have not been outside at all tonight, and am not wearing the same pants as before. Have been sitting here on the couch in the living room for the last few hours, minding my own business.

I now have a small grouping of bites on my right thigh.

As I now recall, in the 2008 incident, the couch was the prime suspect.

 

[stinkbomb12]

damn. when sitting outside and there are bugs, i just fart to keep em away haha!

 

[DaveC426913]

haha. Way to make a good first impression stink.

 

[FlexGunship]

Well, then they waited around for 12 hours before biting.

It's not totally impossible; or it could be a delayed reaction, too (especially if they turn out to be bed bugs or fleas). I once had a wasp inside my undershirt which was content until about 5 hours later...

...I thought I was going to die.

 

[lisab]

Maybe it's hives?

 

[turbo]

Update:

Have not been outside at all tonight, and am not wearing the same pants as before. Have been sitting here on the couch in the living room for the last few hours, minding my own business.

I now have a small grouping of bites on my right thigh.

As I now recall, in the 2008 incident, the couch was the prime suspect.

Do you have a dog or cat? The mites responsible for causing sarcoptic mange may find living on your pet intolerable if you have used Front-Line or other similar treatments on your pet, and they WILL bite you. I visited a friend whose dog was suffering from mange earlier this summer and sat with the dog for a while (he's a pretty chummy mutt). By the time I got home, I noticed three mosquito-bite-like welts on the underside of my forearm, and they itched like crazy for days. They were pretty much gone in under a week, but were far more persistent than mosquito bites.

BTW, any place that has a population of fox, coyotes, etc will have these mites, and pets will bring them into your home from outside, even if they have been given flea/tick treatments.

 

[stinkbomb12]

haha. Way to make a good first impression stink.

haha thanx

 

[DaveC426913]

Do you have a dog or cat? The mites responsible for causing sarcoptic mange may find living on your pet intolerable if you have used Front-Line or other similar treatments on your pet, and they WILL bite you. I visited a friend whose dog was suffering from mange earlier this summer and sat with the dog for a while (he's a pretty chummy mutt). By the time I got home, I noticed three mosquito-bite-like welts on the underside of my forearm, and they itched like crazy for days. They were pretty much gone in under a week, but were far more persistent than mosquito bites.

BTW, any place that has a population of fox, coyotes, etc will have these mites, and pets will bring them into your home from outside, even if they have been given flea/tick treatments.

The only pets I have would result in drowned fleas...
OK, unless you count the Roomba as well.


I hate to suggest it but frankly, both my chill'uns spend all their time at their gf's houses, who do have cats. And both were here that day.

 

[DaveC426913]

Downdate (opposite of an update):

The bites on my right thigh are nowhere near as itchy as the ones under my left knee. 12 hours later, I'm not even sure they're still there.

The bites under my knee have finally receded. Still a little swelling and itch, but both are down by about 80%. (Actually, that didn't take as long as I would have thought. It's been barely 4 days.)

 

[chemisttree]

In https://www.physicsforums.com/showthread.php?t=262090" thread, which was created around the same time of the year (fall) about two years ago, you had a similar episode. Chemisttree thought they might be chiggers (post #15). Could this be a repeat occurrence? Were you able to verify if they were chiggers or not?

I was just thinking the same thing. Of course I remembered the post for some reason.

 

[Danger]

Are you sure that it isn't just heat-rash, Dave? Face it, dude, your thighs are bigger around than my entire body, and the back of the knees is one of the few holdouts wherein the sun never shines.

Just thinking out loud...