|
Department of Public Health
Announces First Human Case of West Nile Virus in Illinois of 2025 in
Southern Illinois
[June 25, 2025]
SPRINGFIELD – The Center for
Disease Control and Prevention (CDC) has confirmed Illinois’ first
human case of West Nile virus (WNV) of 2025 in an individual from
Southern Illinois who was hospitalized due to complications of the
infection. About one in 150 people who contract the disease caused
by a bite from an infected mosquito develop a severe illness that
can affect the brain, spinal cord, nerves and even cause paralysis.
The case marks the earliest onset of illness observed in Illinois
since 2016, and underscores the risk posed by mosquito bites,
especially to those who are over 65 or immunocompromised.
So far in 2025, WNV has been confirmed in 19 counties. The first WNV-positive
mosquito batch of this year was found May 9 in Rockford. In 2024,
there were 69 confirmed human cases of WNV including 13 deaths, the
highest number since 17 WNV-related human deaths recorded in 2018.
“The fact that we are seeing the
first human case of West Nile virus so early in the season serves as
a timely reminder – especially for seniors and those with weakened
immune systems – to protect yourself from illnesses caused by
mosquito bites,” said IDPH Director Dr. Sameer Vohra. “I encourage
all Illinoisans to ‘Fight the Bite’ and take precautions to protect
themselves and their loved ones.”
IDPH urges the public to Fight the Bite by practicing the three
“R’s” – reduce, repel, and report:
REDUCE - 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.
Eliminate, or refresh each week, all sources of standing water where
mosquitoes can breed, including water in bird baths, ponds,
flowerpots, wading pools, old tires, and any other containers.
REPEL - when outdoors, wear shoes and socks, long pants and a
light-colored, long-sleeved shirt, and apply an EPA-registered
insect repellent that contains DEET, picaridin, oil of lemon
eucalyptus, IR 3535, para-menthane-diol (PMD), or 2-undecanone
according to label instructions. Consult a physician before using
repellents on infants.
REPORT – report locations where you see water sitting stagnant for
more than a week such as roadside ditches, flooded yards, and
similar locations that may produce mosquitoes. The local health
department or city government may be able to add larvicide to the
water, which will kill any mosquito larvae.
[to top of second column] |
A county is
considered positive for West Nile virus if a mosquito, horse or
human from that county tests positive for the virus. The
counties to report WNV so far this year included Bureau,
Christian, Clinton, Cook, DeKalb, DuPage, Fulton, Grundy,
Hancock, Henry, Marshall, McDonough, McHenry, Peoria, Scott,
Stark, Tazewell, Wayne and Winnebago. Last year, WNV was
confirmed in 72 counties in Illinois.
IDPH supports mosquito control efforts throughout the state by
providing $2.8 million in funding to Illinois’ 97 local health
departments for vector surveillance and control activities. This
includes purchasing and applying larvicide, working with
municipal governments and local news media for WNV prevention
and education, and investigating mosquito production sites and
nuisance mosquito complaints. Local health departments collect
mosquitoes for West Nile virus testing.
Monitoring for WNV in Illinois includes tests for mosquito
batches, as well as testing sick horses and humans with West
Nile virus-like symptoms.
West Nile virus is transmitted through the bite of a Culex
mosquito, commonly called a house mosquito, that has picked up
the virus by feeding on an infected bird. Common symptoms
include fever, nausea, headache and muscle aches. Symptoms may
last from a few days to a few weeks. Most people infected with
West Nile virus will not show any symptoms; however, in rare
cases it can lead to severe illness including paralysis,
meningitis or encephalitis (i.e. brain and nerve infections), or
even death. People older than 60 and those with weakened immune
systems are at highest risk for severe illness.
Click
here for additional information about West Nile virus.
[Illinois Dept. of Public Health]
 |
