OT (sort of): mosquito resistance

I decided to do a marathon observing session the other night only to be
greeted by what seemed like an infinite number of mosquitos. So, out the
trusty 99% deet bottle came, and I carefully sprayed my legs, arms, and
torso. Always heard that 90% deet or better, just sprayed on a few random
spots would keep them at bay. Not so the other night! ANYWHERE I missed,
and no matter how small the area, and they were there biting. I hadn't
noticed this on previous occasions and I don't like to cover myself in this
chemical. What's going on? Were there just a lot more mosquitos that night
because of the frequent rains and high humidity I've been having, or are
they getting immune to deet?

W.F.

"W. F. Franklin" wrote ...
.......or are they getting immune to deet?


For those of us in other parts of the world, what is 'deet'?
Obviously some kind of insect repellant, but what?

On Thu, 05 Aug 2004 14:33:58 GMT, "W. F. Franklin"
wrote:

I decided to do a marathon observing session the other night only to be
greeted by what seemed like an infinite number of mosquitos. So, out the
trusty 99% deet bottle came, and I carefully sprayed my legs, arms, and
torso. Always heard that 90% deet or better, just sprayed on a few random
spots would keep them at bay. Not so the other night! ANYWHERE I missed,
and no matter how small the area, and they were there biting. I hadn't
noticed this on previous occasions and I don't like to cover myself in this
chemical. What's going on? Were there just a lot more mosquitos that night
because of the frequent rains and high humidity I've been having, or are
they getting immune to deet?

I've used DEET for close to 30 years, and it has always been my experience that
any area untreated is a prime target. DEET repels essentially on contact, so it
is necessary to cover all bare skin. What you are describing sounds like normal
behavior, so I think you might have just been lucky in the past with selective
application.

That said, I think mosquitoes are especially attracted to certain parts of the
body, presumably because of the way we sweat and radiate heat. You are more
likely in general to be bitten on the face, neck, back of fingers, and hands
than other places, so using DEET in those places is probably most effective if
you don't want to cover yourself completely.

I haven't heard that mosquitoes are developing DEET immunity, which is one
reason it is still recommended as a primary first defense against mosquito
bites.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

"Roger Hamlett" wrote ...

It is available in other parts to:
http://www.deet-insect-repellent.co.uk/

Thanks Roger. Having not heard of it, I had assumed it was a US product.

cheers

Henry in Sussex

On Thu, 05 Aug 2004 14:33:58 GMT, "W. F. Franklin"
wrote:

I decided to do a marathon observing session the other night only to be
greeted by what seemed like an infinite number of mosquitos. So, out the
trusty 99% deet bottle came, and I carefully sprayed my legs, arms, and
torso. Always heard that 90% deet or better, just sprayed on a few random
spots would keep them at bay. Not so the other night! ANYWHERE I missed,
and no matter how small the area, and they were there biting. I hadn't
noticed this on previous occasions and I don't like to cover myself in this
chemical. What's going on? Were there just a lot more mosquitos that night
because of the frequent rains and high humidity I've been having, or are
they getting immune to deet?


I'm not sure what part of the country you are from, but here in South
Dakota, you pretty much have to be 100% covered. I use a combination
of spray for clothes and liquid for my arms, neck, face, etc. to
ensure complete coverage.

Mark

"Henry" wrote in message
...
"W. F. Franklin" wrote ...
.......or are they getting immune to deet?


For those of us in other parts of the world, what is 'deet'?
Obviously some kind of insect repellant, but what?
It is available in other parts to:
http://www.deet-insect-repellent.co.uk/
Deet, is a 'short name', for diethyl-meta-toluamide, and is a very
effective repellant, but has been linked to a number of skin complaints
(especially in children), and some effects (like potential damage to
climbing ropes, and softening of some plastics), which tends to make most
people 'think twice' about being too heavy handed with it...
There are also a number of different 'encapsulation' methods that can
affect the severity of these effects.

Best Wishes

"Chris L Peterson" wrote in message
...
On Thu, 05 Aug 2004 14:33:58 GMT, "W. F. Franklin"

wrote:

I decided to do a marathon observing session the other night only to be
greeted by what seemed like an infinite number of mosquitos. So, out the
trusty 99% deet bottle came, and I carefully sprayed my legs, arms, and
torso. Always heard that 90% deet or better, just sprayed on a few
random
spots would keep them at bay. Not so the other night! ANYWHERE I
missed,
and no matter how small the area, and they were there biting. I hadn't
noticed this on previous occasions and I don't like to cover myself in
this
chemical. What's going on? Were there just a lot more mosquitos that
night
because of the frequent rains and high humidity I've been having, or are
they getting immune to deet?

I've used DEET for close to 30 years, and it has always been my experience
that
any area untreated is a prime target. DEET repels essentially on contact,
so it
is necessary to cover all bare skin. What you are describing sounds like
normal
behavior, so I think you might have just been lucky in the past with
selective
application.

That said, I think mosquitoes are especially attracted to certain parts of
the
body, presumably because of the way we sweat and radiate heat. You are
more
likely in general to be bitten on the face, neck, back of fingers, and
hands
than other places, so using DEET in those places is probably most
effective if
you don't want to cover yourself completely.

I haven't heard that mosquitoes are developing DEET immunity, which is one
reason it is still recommended as a primary first defense against mosquito
bites.


Thanks, Chris. I really don't like getting this spray near the equipment
either, so I always spray and rub in pretty far away. I've been considering
doing away with the spray completely and using a mosquito attraction device.
I've seen these units in Home Depot and other DIYs, but they are expensive-
around $300 US as I recall. I hear they work quite well without chemicals
(using hormones instead?), but I don't know.

W.F.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

"sdastroguy" wrote in message
...
On Thu, 05 Aug 2004 14:33:58 GMT, "W. F. Franklin"
wrote:

I decided to do a marathon observing session the other night only to be
greeted by what seemed like an infinite number of mosquitos. So, out the
trusty 99% deet bottle came, and I carefully sprayed my legs, arms, and
torso. Always heard that 90% deet or better, just sprayed on a few
random
spots would keep them at bay. Not so the other night! ANYWHERE I
missed,
and no matter how small the area, and they were there biting. I hadn't
noticed this on previous occasions and I don't like to cover myself in
this
chemical. What's going on? Were there just a lot more mosquitos that
night
because of the frequent rains and high humidity I've been having, or are
they getting immune to deet?


I'm not sure what part of the country you are from, but here in South
Dakota, you pretty much have to be 100% covered. I use a combination
of spray for clothes and liquid for my arms, neck, face, etc. to
ensure complete coverage.

This is the first time I've had to be totally covered. Usually only
selected areas covered did the trick, but the other night they persisted.
No wonder they've been around so much longer than us!

W.F.


Mark

"Roger Hamlett" wrote in message
...

"Henry" wrote in message
...
"W. F. Franklin" wrote ...
.......or are they getting immune to deet?


For those of us in other parts of the world, what is 'deet'?
Obviously some kind of insect repellant, but what?
It is available in other parts to:
http://www.deet-insect-repellent.co.uk/
Deet, is a 'short name', for diethyl-meta-toluamide, and is a very
effective repellant, but has been linked to a number of skin complaints
(especially in children), and some effects (like potential damage to
climbing ropes, and softening of some plastics), which tends to make most
people 'think twice' about being too heavy handed with it...

I don't like using it around the optics, always thinking that "by accident"
some will end up on the scope or camera. I've been concerned about this
enough that I have been thinking of using one of those mosquito attractant
generators. I've seen them in Home Depot and they retail about $300
(ouch!), but if they work it might be worth it.

W.F.

There are also a number of different 'encapsulation' methods that can
affect the severity of these effects.

Best Wishes

On Thu, 05 Aug 2004 16:18:08 GMT, "W. F. Franklin"
wrote:

Thanks, Chris. I really don't like getting this spray near the equipment
either, so I always spray and rub in pretty far away. I've been considering
doing away with the spray completely and using a mosquito attraction device.
I've seen these units in Home Depot and other DIYs, but they are expensive-
around $300 US as I recall. I hear they work quite well without chemicals
(using hormones instead?), but I don't know.

They don't work well at all. There have been several consumer group
evaluations of these, all of which came to this same conclusion. DEET
is always the recommendation - safe and effective when used properly,
but it *will* dissolve certain plastics (personal experience) and is
said to attack lens coatings (dunno, never been there, thank
goodness!).

Wayne Hoffman
33° 49" 17' N 117° 56" 41' W
"Don't Look Down"

http://users.adelphia.net/~w6wlr/