Article: Are You a Mosquito Magnet?

In this time of increasing outdoor fun, a lot of people want to know how to beat the becoming dinner blues. I have reposted the article in it's entirety, but give SERIOUS WARNING to anyone who considers using DEET-containing repellants. DEET is effective, but deadly. I forget where I saw it, but catnip oil is just as effective as DEET (yes there are scientific studies). I am currently in the process of developing a Snake Oil based, chemical free, mosquito repellant that is applied via a stick-type applicator so that your hands don't end up covered in repellant-goo. You'll just have to bear with me in waiting for that one to come to fruition. *chuckle*)

Experts try to crack the code behind why mosquitoes like some humans more
than others.
By Elizabeth Heubeck, M.A.
WebMD Feature


You're flipping burgers for the neighborhood barbecue, and the mosquitoes
have already begun their feast -- on you. As you swat madly at the pests, you
notice other folks seem completely unfazed. Could it be that mosquitoes prefer
dining on some humans over others? This may clear up the mystery.
It's true. Mosquitoes do exhibit blood-sucking preferences, say the experts.
"One in 10 people are highly attractive to mosquitoes," reports Jerry
Butler, PhD, professor emeritus at the University of Florida. Incidentally, it's
not dinner they're sucking out of you. Female mosquitoes -- males do not bite
people -- need human blood to develop fertile eggs. And apparently, not just
anyone's.
Who Mosquitoes Like Best
While researchers have yet to pinpoint what mosquitoes consider an ideal
hunk of human flesh, the hunt is on. "There's a tremendous amount of research
being conducted on what compounds and odors people exude that might be
attractive to mosquitoes," says Joe Conlon, PhD, technical advisor to the American
Mosquito Control Association. With 400 different compounds to examine, it's an
extremely laborious process. "Researchers are just beginning to scratch the
surface," he says.
Scientists do know that genetics account for a whopping 85% of our
susceptibility to mosquito bites. They've also identified certain elements of our body
chemistry that, when found in excess on the skin's surface, make mosquitoes
swarm closer.
"People with high concentrations of steroids or cholesterol on their skin
surface attract mosquitoes," Butler tells WebMD. That doesn't necessarily mean
that mosquitoes prey on people with higher overall levels of cholesterol,
Butler explains. These people simply may be more efficient at processing
cholesterol, the byproducts of which remain on the skin's surface.
Mosquitoes also target people who produce excess amounts of certain acids,
such as uric acid, explains entomologist John Edman, PhD, spokesman for the
Entomological Society of America. These substances can trigger the mosquitoes'
olfactory sensations, or sense of smell, causing them to launch their
"landing" onto unsuspecting victims.
But the process of attraction begins long before the landing. Mosquitoes can
smell their dinner from an impressive distance of up to 50 meters, explains
Edman. This doesn't bode well for people who emit large quantities of carbon
dioxide.
"Any type of carbon dioxide is attractive, even over a long distance,"
Conlon says. Larger people tend to give off more carbon dioxide, which is why
mosquitoes typically prefer munching on adults to small children. Pregnant women
are also at increased risk, as they produce a greater-than-normal amount of
exhaled carbon dioxide. Movement and heat also attract mosquitoes.
So if you want to avoid an onslaught of mosquito bites at your next outdoor
gathering, stake out a chaise lounge rather than a spot on the volleyball
team. Here's why. As you run around the volleyball court, the mosquitoes sense
your movement and head toward you. When you pant from exertion, the smell of
carbon dioxide from your heavy breathing draws them closer. So does the lactic
acid pouring from your sweat glands. And then -- gotcha.
Where Mosquitoes Lurk
Even if your body chemistry doesn't attract mosquitoes, where you're located
might.
Some of the worst mosquito populations exist along coastal areas, Conlon
tells WebMD. And being several miles inland does not guarantee your safety from
the pests. "They'll fly 40 miles for a meal," Conlon says.
Are You a Mosquito Magnet?
While any water source is potential breeding grounds for mosquitoes, they
much prefer stagnant water. So if you crave a mosquito-free water oasis on your
property, forego the backyard pond and seek out a babbling brook instead.
"Even in a desert area, mosquito biting tends to be intense around a water
source," Conlon says.
Can you find respite high in the mountains? Don't count on it. Although
they're generally not active below 55 degrees Fahrenheit, mosquitoes have been
sighted in the Himalayan Mountains, Conlon tells WebMD.
How about cold climates in places such as Alaska? You're safe for most of
the year. But, says Conlon, mosquitoes flock there for a brief, three-week
period between July and August. "The Arctic National Refuge is one big bog,"
Conlon explains, making the mosquito population there second only to that in the
Florida Everglades.
With a long track record -- mosquitoes have been around for 170 million
years -- and more than 175 known species in the U.S., these shrewd summertime
pests clearly aren't going to disappear any time soon. But you can minimize
their impact.
Keeping the Bite at Bay -- Chemical-Based Repellents
Plenty of mosquito repellents line the shelves of drug stores and
supermarkets each summer, but they're not all created equally.
The majority of available mosquito repellents derive their effectiveness
from chemicals. Protecting the public from mosquitoes since 1957, DEET continues
to be the chemical of choice used in repellents. In repeated studies, it's
been proven the most effective chemical repellent on the market. Repellents
with 23.8% DEET (most formulas contain between 10% and 30%) protect wearers for
about five hours, according to a recent study led by Mark Fradin, PhD,
researcher with Chapel Hill Dermatology. The American Academy of Pediatrics and
other experts suggest that it is safe to apply repellent with low
concentrations of DEET (10% or less) to infants over 2 months old.
In 2005, the CDC began recommending alternatives to DEET for repelling
mosquitoes. Picaridin, which is new to the U.S., has been used worldwide since
1998. It has proven to be as effective as DEET but is more pleasant to use
because it has a light, clean feel and is virtually odorless. Picaridin is safe
for children older than 2 months. This substance is marketed as Cutter Advanced.

The other new CDC recommendation is oil of lemon eucalyptus, which is
available under the Repel brand name. This product offers protection similar to low
concentrations of DEET. Lemon eucalyptus is safe for children older than 3
years.
The chemical IR3535, better known as Avon's Skin-So-Soft, has also been
marketed as a repellent in the U.S. in recent years. To date, research shows it's
much less effective than DEET.
Safety of DEET Repellents
Just how safe is it to coat yourself in a chemical-based product like DEET
just to keep from getting bit by mosquitoes?
"[DEET] has been in use for over 40 years and has a remarkable safety
record. Only few hospitalizations have been reported, mainly due to gross overuse,"
Conlon tells WebMD.
The Environmental Protection Agency (EPA), after extensively assessing the
safety of DEET, concluded that "as long as consumers follow label directions
and take proper precautions, insect repellents containing DEET do not present
a health concern." The agency does, however, offer the following safety
strategies for DEET use:
* Follow label directions and precautions.
* Use sparingly.
* Avoid spraying on or near open skin, eyes, mouth, and nose, under
clothing, or near food.
* Wash treated skin with soap and water.

The American Academy of Pediatrics (AAP) provides these additional
recommendations for DEET use on children:
* Select the lowest concentration effective for the amount of time
spent outdoors.
* Avoid use on infants under 2 months of age.
* Avoid repeated applications, which may increase the potential toxic
effects of DEET.

Alternative Repellents
Want to avoid chemical-based repellents altogether? Alternatives do exist,
with one or two showing promise.
"Of the products we tested, the soybean oil-based repellent was able to
protect from mosquito bites for about 1.5 hours," Fradin reports. He and fellow
researchers found other oils -- citronella, cedar, peppermint, lemongrass, and
geranium -- provide short-lived protection at best. Oil-of-eucalyptus
products, however, may offer longer-lasting protection, preliminary studies show.
Hate to spray or slather yourself with any product, either chemical- or
plant-based? Mosquito traps, a relatively new product, may be the answer. They
work by emitting substances that biting mosquitoes find attractive -- such as
carbon dioxide, heat, moisture, and other mosquito-friendly byproducts. They
attract, then trap or kill female mosquitoes. When placed strategically near
breeding spots "they have knocked [mosquito] populations down," Conlon tells
WebMD.
So, is it worth the effort it takes to prevent mosquitoes from nipping at
your ankles? Yes, if you don't want to be bothered by bouts of mosquito-induced
itching all summer long. Certainly, if you are one of the few unfortunate
souls in whom mosquito bites result in severe allergic reactions. And most
definitely if you believe you're likely to be exposed to potentially fatal
mosquito-borne diseases, some of which are becoming increasingly common. Take the
mosquito-transmitted West Nile virus, for instance which Conlon says "is
probably here to stay." And with it, the age-old, ever-adaptable mosquito.
Published July 12, 2004.
Medically updated May 25, 2006.
____________________________________

SOURCES: Jerry Butler, PhD, Professor Emeritus, University of Florida. Joe
Conlon, PhD, technical advisor, American Mosquito Control Association. John
Edman, PhD, Entomological Society of America; and Center for Vector-Borne
Disease Research, University of California-Davis. Mark Fradin, PhD, Chapel Hill
Dermatology, North Carolina. Environmental Protection Agency web site. The
American Academy of Pediatrics Committee on Environmental Health web site.