|
|
The Project!
West Nile Virus...what it is!
After its first appearance in late 1999 in New York, the West Nile Virus (WNV),
a viral form of St. Louis Encephalitis, sent waves of fear coursing through
disease control experts in the United States. Being spread by mosquitoes,
WNV is a serious threat to humans, birds, and other animals. With symptoms
that include fever, head and body aches, and swollen lymph nodes, it is
quite easy to take WNV as a simple house cold and not realize what it is
until too late. WNV has only been known to seriously affect adults over 50,
children under the age of 3 years, and other people with weak immune
systems. There is no cure currently known for WNV, although there is a
preventative vaccine that will help to fight against the effects of the
virus. Currently, the Center for Disease Control and Prevention is
scrambling to come up with an effective antibiotic and a foolproof vaccine
that will help to quell the expected outbreak in the summer of 2002.
Two warm winters in a row followed by rainy springs have combined to allow
an expected explosion in the mosquito population. In addition to the larger
mosquito population, the population of mosquito predators, insects such as
the preying mantis and ladybugs, has drastically decreased over the past
three years due to incredibly dry summers. This huge increase in the
mosquito population will lead to a larger percentage of female mosquitoes
carrying the West Nile Virus and other related diseases. Extreme precautions
are being taken by the CDC and local disease control authorities to help
prevent such an outbreak, but the prospects of prevention look very dim.
The expected outbreak in the summer of 2002 is likely to have an effect on
humans as well as other animals. Information form the vector control
division of the CDC states that most cases of WNV are expected to be in
birds and other animals, with only about five percent or less of the cases
directly affecting humans. These expectations have been influenced by the
fact that so few cases have been seen in humans to date and that WNV is only
known to affect a limited group of humans.
Back to Top
How it is transmitted.
There are hundreds of types of mosquitoes flying around the world at any one
time. Only about 128 of these have been identified inside the United
States,
with about two-fifths of those being found in Illinois. Of those 47
mosquito
species found in Illinois, only 16 overall are known to carry some sort of
disease or virus. Only two of those sixteen species have ever been
found in
large numbers in the Chicago land area, with the other fourteen only having
been sighted in other parts of the world. Those two mosquito species
are
known as culex pipiens and aedes aegpti. Although to the untrained eye
these
two mosquitoes look exactly the same as all other mosquitoes, there are a
few
differences. The aedes has tiger-like spots on the legs and abdomen,
and is
therefore known as the “tiger mosquito.” The culex has wide
bristles on the
top of the head, as well as a hairy abdomen. The culex is also known
more
commonly as the ”house mosquito” or “common mosquito” and can
be found at just about any backyard barbecue or party. Culex are the
only known species in the United States to carry St. Louis Encephalitis and
West Nile Virus.
Back to Top
How to prevent it.
There are many ways to prevent against being infected by a virus or bacteria
carrying mosquito. There are measures that can be taken to prevent direct
infection by mosquitoes, and there are measures that can be taken to prevent
against the breeding of mosquitoes, thus preventing infection.
The most logical are the ways to prevent against direct infection from
mosquito bites. Preventative measures include:
-
Wearing long sleeved shirts and long
pants to minimize the area of skin being presented to the mosquito.
-
-Spraying mosquito repellent with a small
concentration of DEET on the clothing.
-
Wearing a hat to cover the head and protect the
scalp from bites.
-
Using a store bought, area wide yard spray
such as “Yard Guard” to keep mosquitoes from flying in your area.
All of these preventative measures are quite cheap and are
very simple to perform. To ensure your safety and the safety of others,
please take caution whenever you will be exposed to mosquitoes.
There are also logical ways of preventing against mosquito bites that do not
directly involve human to mosquito contact. These measures include:
-
Draining any areas in which water has become
stagnant including: bird baths, decorative ponds, discarded tires,
or any other place where water does not drain.
-
Adding a larvae inhibitor to any standing water
sources that are meant to be there, as well as to moving water sources
as a preventative measure.
-
Adding mosquito pupae and larvae eating animals
such as mosquito fish, frogs, and lady bugs.
-
Contacting your local mosquito abatement district
with any complaints about mosquito annoyances or with information about
potential mosquito breeding sites in your area.
Back to Top
Encephalitis in general.
Encephalitis is an inflammation of the brain tissue. It can be caused by
many different organisms, but viruses are the most common causes. Viruses
that cause cold sores and cold sore like infections have been known, in rare
cases, to move to the brain and cause severe swelling. Arboviruses, spread
by mosquitoes and ticks, are another source for encephalitis. Over 95% of
people bitten by mosquitoes and other insects with an arbovirus do not
develop any symptoms, and those that do rarely get severe cases of
encephalitis. Rabies has also been blamed for encephalitis, and this form of
encephalitis is almost always fatal unless treated before symptoms occur.
Treatment for encephalitis is very basic. Supportive care in an intensive
care unit at any major hospital will allow the body’s natural immune
system to fight the virus that is causing the swelling of the brain. In
extreme cases, surgery may be performed on the skull to allow the brain more
room in its swollen state. There is no current vaccine or effective cure for
encephalitis, although acyclovir, an antibiotic, has been known to reduce
risk of death by 50-60% even after symptoms have been noticed.
In general, cases of encephalitis are extremely rare in the United States,
with only approximately 15,000 confirmed cases in the in 2000. 90% of these
cases were in elderly people over the age of 50 who had weakened immune
systems. The remaining 10% of cases were in young children under the age of
3 years with weak immune systems or improperly developed immune systems.
Back to Top
Other Stuff You Might Want To Know
There are many other diseases of concern to humans other than West Nile
Virus. These include diseases transmitted in ways other than just by
mosquitoes. For example, diseases can be passed to humans through other
insects such as bed bugs, cockroaches, ticks, and even ants.
A very well known disease that humans can get from an insect is lyme
disease. Lyme disease is transmitted through the deer tick, which can be
found in just about every state in the United States. Lyme disease is less
of a concern now that a vaccine and cure has been found for it, but in the
past few years it had been quite a threat. There are thousands of other
diseases that can be transmitted through insects, many that are deadly to
humans.
The contraction of these diseases can all be prevented with the same basic
precautions taken against mosquitoes. Since it is necessary for the disease
to be transmitted from a biting insect, a repellent that makes the insect
not like the taste or smell of you will be the most effective. After that,
there are other measures that can be taken. For example, if you are in an
area where the tick population is known to be large, wearing clothing that
covers the entire body, including a hat of some sort, and sturdy shoes with
long socks is the best way to prevent against ticks. Also, after being out
in the wilderness, it is very important that every area of the body is
checked for burrowing ticks, especially warm, dark areas of the body. Ticks
can be removed from the body in various ways if they are already burrowed.
One effective way is to pour some sort of oil over the tick, making sure
that it will not be harmful to the human if it gets in the wound. Also,
touching an extinguished match head to the body of the tick may force it to
release itself. If basic precautions are taken to prevent infection, then
there should be very little worry about contracting a vector borne disease.
Back to Top
|Home| |Project|
|About Me| |Links|
|
|
|
