There
are over 3,000 species of mosquitoes
found worldwide, and 120 found in the
United States. Mosquitoes are an
annoyance because of their parasitic
nature. They also can be a serious
health hazard due to their ability to
transmit blood borne parasites that
cause disease.
Unfortunately, most people have
encountered mosquitoes and with them,
mosquito bites. What people might not
know is the role these bites play in the
mosquito biological cycle. Female
mosquitoes require a blood meal to
develop fertile eggs. Males, not having
eggs, do not need blood meals and thus
do not bite. The welts that result from
mosquito bites happen because females
inject saliva under the skin of hosts to
prevent blood from clotting as it is
sucked into the food canal. When people
are allergic to the saliva, itchy welts
are produced.
Since blood is used for reproduction
only, not food, both males and females
rely on sugar for energy. They get this
from plant nectar, fruit juices, and
oozing plants.
Mosquitoes are cold-blooded creatures;
therefore, their activity level is based
on the temperature. They thrive at 80
degrees, become lethargic at 60 degrees
and can't function below 50 degrees.
Because of this temperature requirement,
mosquitoes are active year-round in
tropical climates and only in the summer
in temperate climates. At the onset of
cold in temperate climates, mosquitoes
hibernate throughout the winter in
places such as animal burrows, hollow
logs, and basements.
Mosquitoes have four stages of
development: egg, larva, pupa, and
adult. In their larval and pupal stages,
they stay in water, mainly still water.
This is where the concept of mosquito
control through water removal is
important. By removing standing water
from the premises of a property, removal
of eggs, larva, and pupa is achieved as
well. Many species overwinter in frozen
water as eggs and, in the spring, emerge
to start the cycle of reproduction again
by seeking a bloodmeal and laying more
eggs.
How exactly are mosquitoes attracted to
people? The major way that they seek out
hosts is by following the streams of
carbon dioxide exuded through breathing.
Other desirable factors include dark
clothing, perspiration, and artificial
fragrances from detergents, fabric
softeners, and perfumes.
Besides causing annoyances and minor
discomfort, mosquitoes also cause
disease. In fact, they are the most
formidable transmitters of disease in
the animal kingdom. Disease is
transmitted when the mosquito picks up a
parasite in the blood of a host. When
inside the mosquito, the parasite will
then continue in its life cycle,
multiply, or change form. After laying
eggs as a result of that bloodmeal, the
mosquito will seek another host to
continue laying more eggs. It is at this
point that the parasite is transferred
to the next host. Diseases transferred
in this way are malaria, encephalitis,
yellow fever, and West Nile virus
amongst several others.
To reduce the risk posed by mosquitoes,
you need to reduce the risk of being
bit. There are two ways to do this. The
first is to eliminate population sources
and the second is to protect your body.
Following is a list of ways to reduce
their breeding:
-Dispose of unwanted tin cans and tires
-Clean clogged roof gutters and drain
flat roofs
-Flush sump-pumps weekly
-Stock ornamental pools with fish
-Change water in birdbaths, fountains,
and troughs twice a week
-Clean and chlorinate swimming pools;
when not regularly used, they should be
emptied
-Turn over unused wading pools and other
containers that tend to collect
rainwater
-Cover containers tightly with window
screen or plastic when storing rainwater
for garden use during drought periods
For personal protection for you and your
family, follow these suggestions:
-Wear long-sleeved shirts and long pants
-Stay indoors at dawn and dusk when
mosquitoes are most active
-Use mosquito netting on baby carriages
and playpens when your baby is outdoors
-Make sure screens are repaired and
tightly attached to doors and windows
-Avoid camping overnight near freshwater
swamps to reduce your risk of exposure
to mosquitoes
-Use mosquito repellent and follow
manufacturer's directions on the label
To expand on the last suggestion, to
wear relent, there are certain
precautions that should be taken when
using DEET (N-N-diethyl-meta-toulamide)
containing products. DEET can be applied
to skin and clothing, but has the
potential to damage certain fabrics and
to be absorbed into skin. For this
reason, no repellent with a
concentration above 30-35% should be
used on adults. Additionally, nothing
over 10-15% should be used on children.
Anything above 30-35% does not offer
more protection, although it does last
longer. In the interest of safety, it
would be best to simply reapply
repellent with a lower concentration of
DEET. After your time outdoors, wash
skin with soap and water and launder
clothes that have been sprayed with
repellent.
back to top
