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Welcome to Jo Daviess County, Illinois

Vector Control (West Nile Virus & Lyme Disease Prevention)


The vector control program is designed to provide surveillance, public information, and prevention strategies against disease causing agents, especially mosquitoes and ticks.

Vectors are insects, ticks, rats, mice, birds and other animals that transmit disease-producing organisms to humans. The improper storage, handling, and disposal of tires, improper waste disposal and natural conditions may promote the growth of these vectors. Maintaining landscaping and removing unnecessary items will eliminate places for pests to live and reduce exposure to diseases they may carry.

Mosquitoes and West Nile Virus

West Nile Virus was first identified in Illinois in 2001 and has continued to be identified in humans and animals throughout the state each year. Mild cases of West Nile infections may cause a slight fever or headache. More severe infections are marked by a rapid onset of a high fever with head and body aches, disorientation, tremors, convulsions and, in the most severe cases, paralysis or death. Usually symptoms occur from three to 14 days after the bite of an infected mosquito. Persons at the highest risk for serious illness are those 50 years of age or older.

The best way to help prevent West Nile Virus and other illnesses cause by mosquito bites is to reduce the number of mosquitoes around your home and taking measures to prevent being bitten.  Preventative measures include eliminating places where mosquitoes may live and breed. These pests are attracted to stagnant water so containers which hold water should be emptied or changed frequently. To protect from mosquito bites, avoid being outside during the peak times, which include just before and after sunset and just before dawn. Wearing appropriate clothing and insect repellent is also recommended.

About 500 wild birds are collected throughout Illinois each year and tested for West Nile virus. Tracking the occurrence of the disease in birds helps to predict when cases will start appearing in humans as well as the prevalence of the disease in a particular year. Birds are collected and tested from May through October.

More information about West Nile Virus can be found at:

Illinois Department of Public Health

Ticks and Lyme Disease

Lyme disease is a bacterial disease which is transmitted by the bite of an infected deer tick. It is impossible to tell from its appearance if a tick is carrying the disease, so avoiding tick bites is important. Symptoms of Lyme disease can vary from person to person and also change over the duration of the infection. A physician should be consulted if a rash appears or any other unexplained illness with fever is experienced after a tick bite.

Avoiding tick infested areas is the best way to protect from Lyme disease. Wearing light colored protective clothing and insect repellent if visiting wooded areas or areas with tall grass will help deter ticks from biting. After returning indoors, check for ticks and remove any promptly.

More information about Lyme disease can be found at:

Centers for Disease Control

Illinois Department of Public Health


Rabies is a viral disease that causes acute inflammation of the brain in humans and other mammals.  The disease is transmitted only when the virus is introduced into a bite wound, open cuts in the skin, or onto mucous membranes such as the mouth or eyes.  Early symptoms can include fever and tingling at the site of exposure.  These symptoms are followed by one or more of the following symptoms: violent movements, uncontrolled excitement, a fear of water, an inability to move parts of the body, confusion, and loss of consciousness.  Once symptoms appear, death nearly always results.

In the United States, bat bites are the most common source of rabies infections in humans and dog bites account for less than 5% of cases.  Rodents are very rarely infected with rabies.  Reduce your risk of rabies exposure by “bat-proofing” your home.  If you do wake up to a bat in your room or find a bat in a room with a child, mentally impaired or intoxicated person, you should contact your local Animal Control, and the bat should be safely captured and tested for rabies.  The small sharp teeth of a bat can make a bite difficult to find and you may not be aware you were bitten. You should seek medical advice if you feel you have been exposed.
In the United States, more cats have been reported to have been infected with rabies than dogs.  Protecting your pet by having it vaccinated against rabies will also reduce your risk of exposure.  Contact you veterinarian to start your pet on the recommended vaccination schedule.

For rabies questions, or to report a possible exposure to rabies call Animal Control at 815.776.0326.

The Official Website of Jo Daviess County, Illinois Government