|
When was West Nile
virus first detected in Illinois?
In September 2001 laboratory tests confirmed the presence of West Nile virus
in two dead crows found in the Chicago area. The following year all but two
of the state's 102 counties reported West Nile activity.
What about human cases of West Nile
disease in Illinois?
In August 2002, Illinois reported its first case of West Nile disease and by
the end of the year had counted more human cases (884) and deaths (67) than
any other state in the nation. In 2003, the number of West Nile disease
human cases fell to 54 and only one death and in 2004, there were 60 human
cases and four deaths.
What is the
transmission cycle of West Nile virus in the environment?
Mosquitoes become
infected with West Nile virus when they feed on infected birds. These infected
mosquitoes then can transmit West Nile virus to humans and to other birds and animals
when a mosquito bite occurs.
Is it only
humans who become ill when infected with West Nile virus?
No. Certain
animals also can become ill when infected with West Nile virus. For example, horses
exposed to West Nile virus can develop encephalitis. Also, certain birds – particularly
crows and blue jays – can become ill and die with West Nile virus infection.
What are the
symptoms of West Nile disease?
Most people who are infected have no symptoms or may experience mild
illness, such as a fever and headache, before fully recovering. In some
individuals, particularly the elderly, West Nile virus can cause a serious
disease that affects the brain called West Nile encephalitis. It can cause
permanent neurological damage and be fatal. Symptoms generally occur three
to 15 days following the bite of an infected mosquito and range from a
slight fever, headache, rash, swollen nodes and conjunctivitis (irritation
of the eye) to the rapid onset of a severe headache, high fever, stiff neck,
disorientation, muscle weakness, coma or death. Less than 1 percent of
persons infected with West Nile virus will develop severe illness.
Who is at risk
of contracting West Nile disease?
All residents in
areas with West Nile virus activity are at risk of getting West Nile disease; those
at highest risk of severe disease are persons 50 years of age or older and
those whose immune systems are weakened by illness or medical treatment (for
example, chemotherapy).
Is there a
treatment for West Nile disease?
There is no
specific therapy for West Nile encephalitis. In more severe cases, intensive
supportive therapy – hospitalization, intravenous (IV) fluids, airway
management, respiratory support (ventilator) if needed, prevention of
secondary infections (pneumonia, urinary tract, etc.) and good nursing care
– are indicated.
Is there a
vaccine for West Nile disease?
No human vaccine
for West Nile virus disease exists.
If I travel to
an area where birds with West Nile virus have been reported and I am bitten by a
mosquito, am I likely to get sick?
No. Even in areas
where mosquitoes do carry the virus, very few mosquitoes (usually less than
one out of 500) are infected. The chance that one mosquito bite will be from
an infected mosquito is very small.
If bitten by a
mosquito, should I be tested for West Nile virus?
No. Illnesses
related to mosquito bites are rare. However, you should see a doctor
immediately if you develop symptoms such as high fever, confusion, muscle
weakness or severe headaches. Patients with mild symptoms are likely to
recover completely and do not require any specific medication or laboratory
testing.
Why is the
state testing birds (especially crows) for West Nile virus?
Crows appear to
be highly sensitive to the virus and provide an early warning system for
detecting West Nile virus activity in a community. Knowledge of infected birds in a
neighborhood or community allows public health officials to alert citizens
about the increased risk of mosquito-borne diseases.
What should I
do if I find a dead bird?
If a dead crow
or blue jay is found between May 1 and the end of October and appears to
have died from natural causes, you should report this information to your
local health department. Your local health department will let you know if
it is still collecting and testing dead birds. If the local health
department has stopped collecting birds, you will be provided with
instructions on how to safely dispose of the bird.
What time of
year are mosquito viruses spread?
Viruses are most
likely to be spread during the warm weather months when mosquitoes are most
active, usually beginning in the spring and lasting until the first hard
frost. Most human cases occur in late summer and fall.
Are bird and
wild game hunters at risk for West Nile virus?
Because of their
outdoor exposure, hunters may be at risk if they are in areas with West Nile
virus
activity and are bitten by mosquitoes. If they anticipate being exposed to
mosquitoes, they should apply insect repellent to clothing and skin,
according to label instructions, to prevent mosquito bites. Hunters should
follow the usual precautions when handling wild animals and birds. They
should wear gloves when handling and cleaning birds or animals to prevent
blood exposure to bare hands.
Can a person
contract West Nile disease by eating infected game birds?
Proper cooking
kills the West Nile virus. Consequently, there is no danger associated with eating wild
game that might be infected.
Can West Nile
disease be prevented?
The best way to prevent West Nile disease or any other mosquito-borne
illness is to reduce the number of mosquitoes around your home and
neighborhood and to take personal precautions to avoid mosquito bites. Here
are some suggestions:
-
Avoid being outdoors when mosquitoes are most active, especially between
dusk and dawn.
-
When outdoors, wear shoes and socks, long pants and a long-sleeved
shirt, and apply insect repellent that includes DEET, picaridin or oil
of lemon eucalyptus according to label instructions. Consult a physician
before using repellents on infants.
-
Make sure doors and windows have tight-fitting screens. Repair or
replace screens that have tears or other openings. Try to keep doors and
windows shut, especially at night.
-
Eliminate all sources of standing water that can support mosquito
breeding, including water in bird baths, ponds, flowerpots, wading
pools, old tires and any other receptacles. In communities where there
are organized mosquito control programs, contact your municipal
government to report areas of stagnant water in roadside ditches,
flooded yards and similar locations that may produce mosquitoes.
Can West Nile
disease be prevented?
Call your local health department or the Illinois Department of Public
Health's West Nile virus information toll-free number 866-369-9710, Monday
through Friday 8 a.m - 5 p.m. Or visit the
Department’s West Nile virus Web site
and the
U.S. Centers for Disease Control and
Prevention’s West Nile virus Web site for more information on
West Nile virus.
This
information in a printable pdf file
Source: IDPH
|
the virus was introduced to the U.S., it may
have entered this country in an infected traveler, bird or mosquito.
To
report 