State Reports First Human Case of West Nile Virus
Infection for 2004
Contact:
Patricia Fox, DVM, MPH
(608) 267-9000
Thomas Haupt. M.S
(608) 266-5326
FOR IMMEDIATE RELEASE
(MADISON, August 18, 2004)-State health officials today announced the
first confirmed human case of West Nile virus infection in a Wisconsin
resident for 2004. Test results from the Wisconsin State Laboratory of
Hygiene indicate that an Iowa County resident has tested positive for
antibodies to West Nile virus.
The case was recognized when blood that the person had donated tested
positive for West Nile virus genetic material. The blood products were
immediately destroyed and did not enter the blood supply.
Routine follow-up with the donor indicated that the person had been ill
with headache, fever, stiff neck and swollen lymph nodes for several days
approximately one week before donating the blood. The symptoms were not
severe enough to seek medical care and the person had felt fine for a
number of days before donating blood. The person has recovered from the
infection without any complications.
"This is another case that demonstrates that the screening of
blood is successfully preventing West Nile virus infected blood from
entering the blood supply," said Patricia Fox, West Nile Virus
Coordinator in the Wisconsin Division of Public Health.
Fox stressed that people should continue to donate blood because the
need is so great, especially in the summer. "There is absolutely no
risk of contracting West Nile virus from donating blood," she said.
Fox noted that prospective blood donors are screened with a series of
questions designed to decrease the risk of blood being donated by someone
unknowingly infected with West Nile virus. The testing serves as a back-up
measure.
To decrease the possibility of a person donating West Nile virus
infected blood, any prospective donor who has had a fever, headache or
other symptoms of illness the week or so prior to a blood donation should
discuss these with the nurse at the donation center. The nurse can assess
the risk and determine if it is appropriate for the person to donate blood
at that time.
"These results should not discourage people from giving blood or
receiving transfusions," said Fox. "The screening system
continues to protect the blood supply and blood donations are a critical
part of our medical system."
Symptoms of West Nile virus infection usually show up between 3 to 15
days after being bitten by a mosquito infected with WNV. They can include
headache, high fever, muscle weakness, stiff neck, disorientation,
tremors, convulsions, paralysis and coma. Healthcare providers are urged
to be on the alert for patients who have symptoms consistent with West
Nile virus infection. People who are ill should contact their healthcare
provider.
Most people infected with West Nile virus will have no symptoms at all
or will display only mild symptoms of illness. People over the age of 50
are at greater risk of developing severe illness. It is estimated that
fewer than one out of 150 people who become infected will get severely
ill.
West Nile virus is transmitted to humans through the bite of an
infected mosquito. WNV is not transmitted person to person. Although not
all mosquitoes are infected with the virus, the best protection Wisconsin
residents have against the disease is to reduce their risk of getting
mosquito bites. Personal protective behaviors and reducing mosquito
breeding habitat on one's property are the best tools to prevent disease.
Personal protective measures include:
- limiting the time spent outdoors at dawn and dusk during mosquito
season (June to September) or other times mosquitoes are active,
- wearing light colored long sleeve shirts and pants, shoes, and socks
when outdoors,
- applying insect repellents containing 30% DEET or less when
outdoors,
- ensuring that home window and door screens are in good repair to
prevent mosquito entry.
In addition to taking personal protective precautions, Wisconsin
citizens should make every effort to ensure that they are not breeding
habitat for mosquitoes in their own yards. Steps that can be taken to
eliminate mosquito breeding sites include:
- Disposing of tin cans, plastic containers, ceramic pots or similar
water-holding containers.
- Removing discarded tires.
- Making sure roof gutters drain properly and that down spouts are
clean.
- Changing water in birdbaths regularly.
- Turning over wheelbarrows, wading pools, boats, and canoes when not
in use.
- Landscaping to prevent water from pooling in low-lying areas.
- Keeping weeds, vines and grass trimmed, because mosquitoes use these
shady areas as resting places during hot daylight hours.
West Nile virus has been found in 91 birds in 46 Wisconsin counties in
2004. In addition, five horses and two mosquito pools have also tested
positive for West Nile virus in Wisconsin this year. Nationwide, 495 human
cases have been reported in 24 states and 10 people have died. Last year,
17 Wisconsin residents were ill with West Nile virus but none died.
The Division of Public Health continues to monitor the spread of the
disease using surveillance of dead crows, ravens and blue jays as a tool
to determine the presence of West Nile virus in the state. These dead
birds should be reported to the West Nile Virus Hotline at 1-800-433-1610
or to local health departments.
For more information about West Nile virus and surveillance activities
in Wisconsin, visit: http://www.dhfs.state.wi.us/dph_bcd/WestNileVirus/
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Last Revised: August 18, 2004 |
