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Recent
spring rains have brought an onslaught of mosquitoes. After
living with all of the doors and windows open for weeks, the
nasty blood-sucking creatures are now coming out of every
dark corner of the house. Children and adults are terrified.
Should you be concerned about catching West Nile Virus (WNV)?
The good news: No cases of West Nile Virus
have been reported in Arizona (where I have my medical practise)
yet in 2004. Most people who do get West Nile virus infections
get such a mild illness they may not even know it.
The bad news: In 2003, 13 cases of WNV were
reported to the CDC, which resulted in 1 death and 7 cases
of “neuroinvasive disease,” the most severe type
of WNV infection because it affects a person’s nervous
system, leading to inflammation of the brain or the meninges
around the brain. For those who get a serious case of the
disease can die. Some get a polio-like disease -- which may
leave them partially paralyzed. Other survivors of serious
West Nile virus infection may have permanent nerve damage
or long-lasting fatigue.
Historical
Background (back
to top)
West Nile virus emerged in the 1930s in the West Nile district
of Uganda. It became established in Egypt and in 1957 caused
an outbreak of encephalitis in Israel. In the early 1960s it
began infecting horses in France.
West Nile virus arrived in New York in 1999, probably on the
wings of an infected bird. From 1999 through 2001, the virus
caused 149 cases of human illness in the U.S. There were 18
deaths.
Then came 2002. The virus spread from coast to coast. There
were more than 4,100 documented human cases and 284 deaths.
Experts agree that West Nile virus is now a permanent part of
our summers. Nobody knows how big a problem it will be in any
given year.
A bit of perspective is in order here. West Nile virus is scary,
but it's far from the worst virus living in the U.S. --- the
flu kills 50,000 to 70,000 Americans every year.
Many of the mosquitoes that carry West Nile virus die during
the winter. But plenty of them survive. At first, there are
so few of them that human infections are rare.
Eventually, however, numbers of mosquitoes that carry West
Nile virus rise to dangerous levels. Human infections become
more common.
Many
experts believe that once a person recovers from West Nile
virus infection -- even if there was no illness -- he or she
is protected against future infection. But nobody knows for
sure.
CDC
Factsheet: What You Need To Know (back
to top) What
Is West Nile Virus?
West Nile virus (WNV) is a potentially serious illness. Experts
believe WNV is established as a seasonal epidemic in North
America that flares up in the summer and continues into the
fall. This fact sheet contains important information that
can help you recognize and prevent West Nile virus.
What Are the Symptoms of WNV?
WNV affects the central nervous system. Symptoms vary.
- No
Symptoms in Most People. Approximately 80 percent of people
who are infected with WNV will not show any symptoms at
all.
- Mild
Symptoms in Some People. Up to 20 percent of the people
who become infected will display mild symptoms, including
fever, headache, and body aches, nausea, vomiting, and sometimes
swollen lymph glands or a skin rash on the chest, stomach
and back. Symptoms typically last a few days.
- Serious
Symptoms in a Few People. About one in 150 people infected
with WNV will develop severe illness. The severe symptoms
can include high fever, headache, neck stiffness, stupor,
disorientation, coma, tremors, convulsions, muscle weakness,
vision loss, numbness and paralysis. These symptoms may
last several weeks, and neurological effects may be permanent.
How
Does It Spread?
- Infected
Mosquitoes. Generally, WNV is spread by the bite of an infected
mosquito. Mosquitoes are WNV carriers that become infected
when they feed on infected birds. Infected mosquitoes can
then spread WNV to humans and other animals when they bite.
- Transfusions,
Transplants, and Mother-to-Child. In a very small number
of cases, WNV also has spread through blood transfusions,
organ transplants, breastfeeding and even during pregnancy
from mother to baby.
- Not
through touching. WNV is not spread through casual contact
such as touching or kissing a person with the virus.
How Soon Do Infected People Get Sick?
People typically develop symptoms between 3 and 14 days after
they are bitten by the infected mosquito.
How Is WNV Infection Treated by Conventional Medicine?
There is no specific treatment for WNV infection. In cases
with mild symptoms, people experience symptoms such as fever
and aches that pass on their own. In more severe cases, people
usually need to go to the hospital where they can receive
supportive treatment including intravenous fluids, help with
breathing and nursing care.
Note:
See TREATMENT below for Dr. Hansen’s
recommendations.
What Should I Do if I Think I Have WNV?
Mild WNV illness improves on its own, and people do not necessarily
need to seek medical attention for this infection. If you
develop symptoms of severe WNV illness, such as unusually
severe headaches or confusion, seek medical attention immediately.
Severe WNV illness usually requires hospitalization. Pregnant
women and nursing mothers are encouraged to talk to their
doctor if they develop symptoms that could be WNV.
What Is the Risk of Catching WNV?
For most, risk is low. Less than 1 percent of people who are
bitten by mosquitoes develop any symptoms of the disease and
relatively few mosquitoes actually carry WNV.
Greater risk for those outdoors a lot. People who spend a
lot of time outdoors are more likely to be bitten by an infected
mosquito. They should take special care to avoid mosquito
bites.
People over 50 can get sicker. People over the age of 50 are
more likely to develop serious symptoms of WNV if they do
get sick and should take special care to avoid mosquito bites.
Risk through medical procedures is low. The risk of getting
WNV through blood transfusions and organ transplants is very
small, and should not prevent people who need surgery from
having it. If you have concerns, talk to your doctor before
surgery.
Pregnancy and nursing do not increase risk of becoming infected
with WNV.
PREVENTION
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What Can I Do to Prevent WNV?
The easiest and best way to avoid WNV is to prevent mosquito
bites.
- When
you are outdoors, use insect repellents containing DEET
(N, N-diethyl-meta-toluamide). Follow the directions on
the package.
- Many
mosquitoes are most active at dusk and dawn. Consider staying
indoors during these times or use insect repellent and wear
long sleeves and pants. Light-colored clothing can help
you see mosquitoes that land on you.
-
Make sure you have good screens on your windows and doors
to keep mosquitoes out.
-
Get rid of mosquito breeding sites by emptying standing
water from flower pots, buckets and barrels. Change the
water in pet dishes and replace the water in bird baths
weekly. Drill drainage holes in tire swings so water drains
out. Keep children's wading pools empty and on their sides
when they aren't being used.
Insect Repellent Use and Safety
DEET, the active ingredient in most tick and insect repellents,
is unequalled when it comes to keeping mosquitoes, ticks,
and other bugs away. DEET is used safely by an estimated 200
million people each year. DEET is produced by Morflex, Inc.
and sold to companies who make consumer insect repellents.
Q
and A's
Q.
Is DEET safe?
A. Yes, products containing DEET are very
safe when used according to the directions. Because DEET
is so widely used, a great deal of testing has been done.
When manufacturers seek registration with the U.S. Environmental
Protection Agency (EPA) for products such as DEET, laboratory
testing regarding both short-term and long-term health effects
must be carried out. Over the long history of DEET use,
very few confirmed incidents of toxic reactions to DEET
have occurred when the product is used properly.
(From the National Pesticide Information Center [NPIC],
EPA re-registration eligibility decision. See http://www.npic.orst.edu/factsheets/DEETgen.pdf
. )
Insect
Repellents and Sunscreen
Q. Can I use an insect repellent containing DEET
and sunscreen at the same time?
A. Yes. People can and should use both
sunscreen and DEET when they are outdoors to protect their
health. Follow the instructions on the package for proper
application of each product. Apply sunscreen first, followed
by repellant containing DEET.
To protect
from sun exposure and insect bites, you can also wear long
sleeves and long pants. You can also apply insect repellent
containing DEET or permethrin to your clothing, rather than
directly to your skin.
Q. Has CDC changed its recommendations for use of
DEET and sunscreen?
A. No. Based on available research, CDC
believes it is safe to use both products at the same time.
Follow the instructions on the package for proper application
of each product. Apply sunscreen first, then insect repellent
containing DEET, to be sure that each product works as specified.
Q. Should I use a combination sunscreen/DEET-based
insect repellent?
A. Because the instructions for safe use
of DEET and safe use of sunscreen are different, CDC does
not recommend using products that combine DEET with sunscreen.
In most
situations, DEET does not need to be reapplied as frequently
as sunscreen. DEET is very safe when applied correctly. The
rare adverse reactions to DEET have generally occurred in
situations where people do not follow the product instructions.
Sunscreen often requires frequent reapplication, so using
a combined product is not recommended. You do not need to
reapply insect repellent every time you reapply sunscreen.
Follow the instructions on the package for each product to
get the best results.
Q.
I heard about a study saying that there may be some type
of interaction between repellents containing DEET and sunscreen.
Is this true?
A. There has been attention to a study
concerning the chemicals in DEET and sunscreen presented
at a scientific meeting. This is an in vitro study, which
means that it is a laboratory study that did not include
human or animal testing. The goal of the study was to examine
absorption of these chemicals, and it did not evaluate or
make conclusions about health effects related to this issue.
The study authors stated that further evaluation of the
interaction of these chemicals should be conducted. The
study has not yet been published (as of July 2003).
Evaluation by the EPA, which regulates products such as
DEET, indicates that it is safe to use insect repellents
containing DEET and sunscreen at the same time. CDC recommends
using two separate products because sunscreen requires frequent
applications while DEET should be used sparingly. Follow
the directions on the package for each product, and consult
your physician or pharmacist if you have questions. CDC's
recommendations for the safe use of insect repellents on
children and adults remain unchanged.
Insect Repellent Use
Q. Why should I use insect repellent?
A. Insect repellents help people reduce
their exposure to mosquito bites that may carry potentially
serious viruses such as West Nile virus, and allow them
to continue to play and work outdoors.
Q. When should I use mosquito repellent?
A. Apply repellent when you are going to be outdoors
and will be at risk for getting bitten by mosquitoes.
Q. What time of day should I wear mosquito repellent?
A. Many of the mosquitoes that carry the West Nile virus
are especially likely to bite around dusk and dawn. If you
are outdoors around these times of the day, it is important
to apply repellent. In many parts of the country, there
are mosquitoes that also bite during the day, and these
mosquitoes have also been found to carry the West Nile virus.
The safest decision is to apply repellent whenever you are
outdoors.
Q. How often should repellent be reapplied?
A. Follow the directions on the product you are
using in order to determine how frequently you need to reapply
repellent. Sweating, perspiration or getting wet may mean
that you need to re-apply repellent more frequently. If
you are not being bitten, it is not necessary to re-apply
repellent. Repellents containing a higher concentration
of active ingredient (such as DEET) provide longer-lasting
protection.
Q. Should I wear repellent while I am indoors?
A. Probably not. If mosquitoes are biting you while
you are indoors, there are probably better ways to prevent
these bites instead of wearing repellent all the time. Check
window and door screens for holes that may be allowing mosquitoes
inside. If your house or apartment does not have screens,
a quick solution may be to staple or tack screening (available
from a hardware store) across the windows. In some areas
community programs can help older citizens or others who
need assistance.
Q. How does mosquito repellent work?
A. Female mosquitoes bite people and animals because
they need the protein found in blood to help develop their
eggs. Mosquitoes are attracted to people by skin odors and
carbon dioxide from breath. Many repellents contain a chemical,
N,N-diethyl-m-toluamide (DEET), which repels the mosquito,
making the person unattractive for feeding. DEET does not
kill mosquitoes; it just makes them unable to locate us.
Repellents are effective only at short distances from the
treated surface, so you may still see mosquitoes flying
nearby. As long as you are not getting bitten, there is
no reason to apply more DEET.
Q. Which mosquito repellent works the best?
A. The most effective repellents contain DEET (N,N-diethyl-m-toluamide),
which is an ingredient used to repel pests like mosquitoes
and ticks. DEET has been tested against a variety of biting
insects and has been shown to be very effective. The more
DEET a repellent contains the longer time it can protect
you from mosquito bites. A higher percentage of DEET in
a repellent does not mean that your protection is better—just
that it will last longer. DEET concentrations higher than
50% do not increase the length of protection.
Q. How does the percentage of DEET in a product
relate to the amount of protection it gives?
A. Based on a recent study:
- A
product containing 23.8% DEET provided an average of 5 hours
of protection from mosquito bites.
- A product
containing 20% DEET provided almost 4 hours of protection
- A product
with 6.65% DEET provided almost 2 hours of protection
- Products
with 4.75% DEET and 2% soybean oil were both able to provide
roughly 1 and a half hour of protection.
Choose a repellent that provides protection for the amount
of time that you will be outdoors. A higher percentage of
DEET should be used if you will be outdoors for several
hours while a lower percentage of DEET can be used if time
outdoors will be limited. You can also re-apply a product
if you are outdoors for a longer time than expected and
start to be bitten by mosquitoes. (For more information,
see Table 1: Fradin and Day, 2002. See Publications page.)
Q. Why does CDC recommend using DEET?
A. DEET is the most effective and best-studied
insect repellent available. (Fradin, 1998). Studies using
humans and mosquitoes report that only products containing
DEET offer long-lasting protection after a single application.(Fradin
and Day, 2002. See Publications page.)
Q. Are non-DEET repellents effective (e.g. Skin-So-Soft,
plant-based repellents)?
A. Some non-DEET repellent products which are
intended to be applied directly to skin also provide some
protection from mosquito bites. However, studies have
suggested that other products do not offer the same level
of protection, or that protection does not last as long
as products containing DEET. A soybean-oil-based product
has been shown to provide protection for a period of time
similar to a product with a low concentration of DEET
(4.75%) (Fradin and Day, 2002).
People should choose a repellent that they will be likely
to use consistently and that will provide sufficient protection
for the amount of time that they will be spending outdoors.
Product labels often indicate the length of time that
protection that can be expected from a product.
Using Repellents Safely
Q. What are some general considerations to remember
in order to use products containing DEET safely?
A. Always follow the recommendations appearing
on the product label.
-
Use
enough repellent to cover exposed skin or clothing. Don't
apply repellent to skin that is under clothing. Heavy
application is not necessary to achieve protection.
-
Do
not apply repellent to cuts, wounds, or irritated skin.
-
After
returning indoors, wash treated skin with soap and water.
-
Do
not spray aerosol or pump products in enclosed areas.
- Do
not apply aerosol or pump products directly to your face.
Spray your hands and then rub them carefully over the face,
avoiding eyes and mouth.
Q.
How should products containing DEET be used on children?
A. No definitive studies exist in the scientific
literature about what concentration of DEET is safe for
children. No serious illness has been linked to the use
of DEET in children when used according the product recommendations.
The American Academy of Pediatrics (AAP) Committee on
Environmental Health has recently updated their recommendation
for use of DEET products on children, citing: "Insect
repellents containing DEET (N,N-diethyl-m-toluamide, also
known as N,N-diethyl-3-methylbenzamide) with a concentration
of 10% appear to be as safe as products with a concentration
of 30% when used according to the directions on the product
labels."
The AAP and other experts suggest that it is acceptable
to apply repellent with low concentrations of DEET to
infants over 2 months old. Other guidelines cite that
it is acceptable to use repellents containing DEET on
children over 2 years of age.
Repellent products that do not contain DEET are not likely
to offer the same degree of protection from mosquito bites
as products containing DEET. Non-DEET repellents have
not necessarily been as thoroughly studied as DEET, and
may not be safer for use on children.
Parents should choose the type and concentration of repellent
to be used by taking into account the amount of time that
a child will be outdoors, exposure to mosquitoes, and
the risk of mosquito-transmitted disease in the area.
Persons who are concerned about using DEET or other products
on children may wish to consult their health care provider
for advice. The National Pesticide Information Center
(NPIC) can also provide information through a toll-free
number, 1-800-858-7378 or npic.orst.edu.
-
Always
follow the recommendations appearing on the product label
when using repellent.
-
When
using repellent on a child, apply it to your own hands
and then rub them on your child. Avoid children's eyes
and mouth and use it sparingly around their ears.
-
Do
not apply repellent to children's hands. (Children may
tend to put their hands in their mouths.)
-
Do
not allow young children to apply insect repellent to
themselves; have an adult do it for them. Keep repellents
out of reach of children.
- Do
not apply repellent to skin under clothing. If repellent
is applied to clothing, wash treated clothing before wearing
again.
Using repellents on the skin is not the only way to avoid
mosquito bites. Children and adults can wear clothing with
long pants and long sleeves while outdoors. DEET or other
repellents such as permethrin can also be applied to clothing
(don’t use permethrin on skin), as mosquitoes may
bite through thin fabric. Mosquito netting can be used over
infant carriers. Finally, it may be possible to reduce the
number of mosquitoes in the area by getting rid of containers
with standing water that provide breeding places for the
mosquitoes.
Q.
Is DEET safe for pregnant or nursing women?
A. There are no reported adverse events following
use of repellents containing DEET in pregnant or breastfeeding
women.
Q.
Are there any risks due to using repellents containing
DEET?
A. Use of these products may cause skin reactions
in rare cases. If you suspect a reaction to this product,
discontinue use, wash the treated skin, and call your
local poison control center. There is a new national number
to reach a Poison Control Center near you: 1-800-222-1222.
If you go to a doctor, take the product with you. Cases
of serious reactions to products containing DEET have
been related to misuse of the product, such as swallowing,
using over broken skin, and using for multiple days without
washing skin in between use, for example. Always follow
the instructions on the product label.
More information
Q. Where can I get more information about repellents?
A. For more information about using repellents
safely please consult the EPA Web site: http://www.epa.gov/pesticides/citizens/insectrp.htm
or consult the National Pesticide Information Center (NPIC),
which is cooperatively sponsored by Oregon State University
and the U.S. EPA. NPIC can be reached at: npic.orst.edu
or 1-800-858-7378.
TREATMENT
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to top)
Dr. Hansen
recommends the following natural herbal and homeopathic agents
for the treatment for West Nile Virus:
PHYTOBIOTIC™
West Nile
Virus is a virus. Conventional medicine has no antiviral drugs
except for the treatment of herpes and HIV. Nature, however,
has provided us with several spectacular antiviral agents
that either kill viruses directly or enhance the immune system
response to kill viruses.
Dr. Hansen
recommends PHYTOBIOTIC™
as the first line of defense at the earliest onset of any
symptoms of infection. Phytobiotic™ is effective for
both viral and bacterial infections.
HOMEOPATHIC
MEDICINES
Belladonna
(Deadly Nightshade) 30C:
Belladonna
is the premier homeopathic remedy for the treatment of infections
that begin with a rapid onset, including fever, headaches,
nausea and vomiting and skin rash over the chest, stomach
and back.
Recommended
Dose: Initially: 3 granules every 30 minutes for 3 doses;
then 3 granules every 4 hours for the first 48 hours; as
the symptoms resolve, reduce the dose to 3 granules 3 times
daily for up to 1 week.
Gelsemium
(Yellow Jasmine) 30C:
Gelsemium
may be needed for more severe symptoms or treatment begun
later in the course of the disease. Gelsemium centers its
action upon the nervous system. It is indicated for the
treatment of fever, headache, neck stiffness, stupor, disorientation,
coma, tremors, convulsions, muscle weakness, vision loss,
numbness and paralysis.
Recommended
Dose: Initially: 3 granules every 30 minutes for 3 doses;
then 3 granules every 4 hours for the first 48 hours; as
the symptoms resolve, reduce the dose to 3 granules 1-3
times daily for up to 3 weeks as needed.
If symptoms
do not resolve or get worse within 48 hours, seek the attention
of qualified physician. Keep the patient well hydrated and
watch for signs of dehydration, including lethargy, listlessness,
dry parched lips, poor skin turgor and decreased urination.
Lathyrus
(Chick-pea) 30C:
Lathyrus
is indicated for the paralytic after effects of West Nile
Virus, including spastic paralysis, muscle wasting, weakness
and heaviness, slow recovery of nerve power, sleepiness,
tremors, tottering gait, excessive rigidity of legs, spastic
gait, cramps in legs, stiffness and lameness of ankles and
knees, difficulty raising toes from floor on walking, etc.
Recommended
Dose: 3 granules once daily for two months; if improvement
occurs, but stops a higher dose may be indicated and patient
should seek the advise of a qualified Naturopathic or Homeopathic
Physician.
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