The Michigan Department of Health and Human Services has announced the first confirmed human case of West Nile virus (WNV) for 2025. The infected person is a resident of Livingston County, though no other details were released. The first case in 2024 was also found in Livingston County. According to Michigan's chief medical executive, Dr. Natasha Bagdasarian, it only takes a single bite from an infected mosquito to cause a severe illness. She advises people to use insect repellent and wear long-sleeved shirts and pants when outside, especially from dusk to dawn, when mosquitoes are most active. So far this year, mosquitoes with the virus have also been found in several other counties, including Bay, Kalamazoo, Kent, Macomb, Midland, Saginaw, Tuscola, and Wayne. What Is West Nile Virus? The Centers of Disease Control and Prevention (CDC) explains that west Nile virus is the most common disease spread by mosquitoes in the continental United States. It is passed to people through the bite of an infected mosquito. The risk of getting the virus is highest during mosquito season, which typically runs from summer through fall. There is currently no vaccine or specific medicine to treat West Nile virus in humans. What to Expect if You're Infected With West Nile Virus Most people who get West Nile virus (about 4 out of 5) will not feel sick at all. About 1 in 5 people will develop what is called West Nile fever, with symptoms that can include:A fever and headacheBody aches and joint painVomiting or diarrheaA skin rashThese symptoms usually last a few days to a few weeks, and most people recover on their own. However, a small number of people, about 1 in 150, will get a serious and sometimes deadly illness. This happens when the virus causes inflammation of the brain (encephalitis) or the lining of the brain and spinal cord (meningitis). Symptoms of this more severe illness include: A high feverA stiff neckConfusion or disorientationSeizures or paralysisA comaWho Is at Risk for West Nile Virus? Your risk of getting West Nile virus goes up if you are exposed to mosquito bites during the summer. While most people who get infected have a mild illness and recover completely, certain people are more likely to get a serious illness from the virus. This includes older people and those with weak immune systems. If a healthcare provider thinks you might have West Nile virus, they will likely order a blood test. This test looks for signs in your blood that your body is fighting the virus. In more serious cases, they may also perform a spinal tap (lumbar puncture) to check the fluid around your brain and spinal cord for signs of infection. How Is West Nile Virus Treated? There is no specific medicine to cure West Nile virus. Treatment focuses on managing your symptoms and supporting your body while it fights the infection. For the most serious cases, such as West Nile encephalitis or meningitis, a person may need to stay in the hospital for intensive care. This care can include: Getting fluids through an IVUsing a breathing machine (ventilator)Receiving care to prevent other infections, like pneumoniaGeneral nursing careHow to Protect Yourself from Mosquito Bites The CDC explains that since there is no treatment for the virus, the best way to protect yourself is to prevent mosquito bites. You can do this by: Using bug repellent Look for products that are approved by the Environmental Protection Agency (EPA). The most effective repellents contain ingredients like DEET, picaridin, or oil of lemon eucalyptus. Getting rid of standing water Mosquitoes lay their eggs in water, so you should remove any standing water around your home. This includes water in buckets, tires, birdbaths, and flowerpots. Wearing protective clothingWhen you are outside, especially from dusk to dawn when mosquitoes are most active, wear long-sleeved shirts and long pants.