Latest news with #WestNileVirus
Time of India
2 days ago
- Health
- Time of India
West Nile virus: Wisconsin reports first case; Here are the early symptoms to know
Wisconsin has confirmed its first human case of West Nile virus (WNV) for 2025, health officials announced July 28. The infection was identified in a resident of Barron County, while mosquitoes in Milwaukee and Lafayette counties also tested positive for the virus. Though most infected individuals show no symptoms, about 1 in 5 infected by West Nile virus (WNV) develop mild illness, while fewer than 1 in 150 may suffer severe, potentially life-threatening neuroinvasive disease. The virus is primarily transmitted to humans through the bite of infected mosquitoes, which acquire the virus by feeding on infected birds. With no vaccine or targeted antiviral treatment available for humans, prevention and awareness are the primary defenses. While most people don't experience severe symptoms, those over 50 and individuals with weakened immune systems are at higher risk for complications like encephalitis or meningitis. What is West Nile Virus? West Nile virus is a single-stranded RNA virus that causes West Nile fever. It is a member of the family Flaviviridae, from the genus Flavivirus, which also contains the Zika virus, dengue virus, and yellow fever virus. The virus is primarily transmitted by mosquitoes, mostly species of Culex. The virus was initially identified in the West Nile district of Uganda in 1937. It has since spread globally, including Africa, Europe, the Middle East, Asia, Australia, and North America. How does WNV spread? West Nile virus (WNV) is primarily spread to humans through the bite of an infected mosquito. Mosquitoes become infected when they feed on birds that carry the virus. Humans, horses, and other mammals can then contract WNV from the bite of an infected mosquito. Mosquitoes, particularly certain species of Culex mosquitoes, are the main vectors for WNV. They become infected when they bite birds that carry the virus. Birds, especially certain species like crows and jays, are considered amplifying hosts, meaning they can carry high levels of the virus in their blood, making them efficient transmitters to mosquitoes. When an infected female mosquito bites a human or other mammal, it injects saliva, which can contain the virus, into the bloodstream. While mosquito bites are the primary route, WNV can also be transmitted through blood transfusions and organ transplants, as well as from mother to child during pregnancy, delivery, or breastfeeding. There have also been rare cases of transmission in laboratory settings and through oral-fecal routes in alligators and crocodiles. However, West Nile virus is not spread through casual contact with infected individuals or through the air. Moreover, mammals like humans are "dead‑end hosts" because they typically don't carry enough virus in their blood to facilitate further mosquito infection. Peak transmission occurs between July and October, a period marked by warm, humid weather that favors mosquito breeding and bird activity. Early symptoms: What to watch for While most people infected with WNV remain symptom-free (around 80%), about 20% develop West Nile fever, a short-lived, flu-like illness. Key symptoms include: Fever and chills Severe headache Body aches and fatigue Rashes Nausea or vomiting Joint pain These symptoms typically appear 2 to 14 days after infection, though incubation can be longer in immune-compromised individuals. Severe illness: Less common, but a serious health hazard Less than 1% of infected people develop neuroinvasive West Nile disease. This severe form can result in: Meningitis: fever, stiff neck, headache Encephalitis: altered mental state, seizures, tremors Acute flaccid paralysis or coma Muscle weakness or difficulty breathing, possibly requiring hospitalization Who are at risk? Although most people infected with West Nile virus remain asymptomatic (~80%), around 20% experience West Nile fever – flu‑like symptoms including fever, headache, fatigue, and sometimes rash. Less than 1% develop neuroinvasive disease (meningitis or encephalitis), marked by high fever, neck stiffness, confusion, tremors, or paralysis – conditions that can be fatal in about 10% of these cases. Individuals over 60, organ transplant recipients, and those with weakened immune systems or certain chronic (comorbid) conditions like diabetes, high blood pressure, or kidney disease are at higher risk of severe West Nile virus illness. While anyone can be bitten by an infected mosquito, these groups are more likely to experience serious complications if infected. Additionally, people with weakened immune systems, due to conditions like HIV/AIDS, cancer, or undergoing chemotherapy, are more susceptible to severe illness. Individuals who have received organ transplants are at increased risk due to the immunosuppressant medications they take to prevent organ rejection. While not a direct risk factor for acquiring the virus, pregnant women and breastfeeding mothers should be cautious and consult with their doctor if they experience symptoms. Precautions and safety tips To prevent West Nile virus (WNV) infection, the most important precaution is to minimize mosquito bites. This involves using insect repellent, wearing protective clothing, and reducing mosquito breeding sites. Additionally, limiting outdoor activities during peak mosquito hours (dusk and dawn) and ensuring proper screening of windows and doors can help reduce exposure. Department of Public Health and the CDC recommend: Avoid peak mosquito activity: Be cautious at dusk and dawn, when Culex mosquitoes are most active. Use EPA‑registered insect repellents: DEET, picaridin, IR3535, or oil of lemon eucalyptus are recommended. Dress smart: When outdoors, especially during peak mosquito hours, wear long sleeves, long pants, and a hat to cover as much skin as possible. Eliminate standing water weekly: Dump water from flowerpots, gutters, and water bowls, as mosquitoes need only a bottlecap's water to breed. Maintain screens and doors: Install and repair screens on windows and doors to keep mosquitoes out. Use mosquito netting: If you are sleeping outdoors or in an unscreened area, use mosquito netting to prevent bites. Be informed and report: Stay updated on local alerts and report stagnant water or dead birds to county health officials. Be aware of travel risks: If traveling to an area with known WNV activity, take extra precautions and consult with your doctor about necessary preventative measures. Maharashtra reports first case of Zika virus
CBS News
2 days ago
- Health
- CBS News
Mosquitoes test positive for West Nile virus on Long Island
More than a dozen mosquito samples on New York's Long Island have tested positive for West Nile virus, health officials say. The 14 positive mosquito samples were taken in Nesconset, Northport, Dix Hills, Melville, Lindenhurst, West Babylon, St. James, Rocky Point and Holtsville, Suffolk County Health Commissioner Dr. Gregson Pigott announced Monday. The samples were collected on July 16. To date, Suffolk has reported 15 mosquito samples testing positive for West Nile virus and four testing positive for Jamestown Canyon virus, Pigott said. "Mosquito activity is picking up with the warmer weather and with it comes the risk of being exposed to West Nile virus," Pigott said. "While there is no cause for alarm, we advise residents to take precautions and cooperate with us in our efforts to reduce exposure to mosquito-borne diseases." West Nile has also been detected in mosquitoes in New York City this year, as experts track a rise in cases nationwide. Suffolk did not report any human cases and neither did the city. West Nile virus has been detected in Suffolk County every year since 1999, when it first appeared, the County Department of Health Services said. There were 21 confirmed cases in 2024 and five in 2023. Two people in New Jersey died from the virus last year. The virus is transmitted to humans when they are bitten by an infected mosquito. "Most people infected with West Nile virus will experience mild or no symptoms, but some can develop severe symptoms including high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness, and paralysis. The symptoms may last several weeks, and neurological effects may be permanent. Individuals, especially those 50 years or older or those with compromised immune systems, are urged to take precautions to avoid being bitten by mosquitoes," according to the county's health department. Suffolk's health commissioner released these tips for preventing mosquito bites:
CBS News
2 days ago
- Health
- CBS News
7 Pittsburgh neighborhoods to be treated after more mosquito samples test positive for West Nile Virus
The Allegheny County Health Department on Monday confirmed that additional mosquito samples have tested positive for West Nile Virus, and seven more Pittsburgh neighborhoods will be treated as a result. The health department will treat areas for mosquitoes in the communities of Point Breeze, Regent Square, Edgewood, Wilkinsburg, East Hills, Homewood, and Highland Park with the pesticide Zenivex E20. Zenivex E20 is classified by the EPA as a low-risk insecticide as it is not harmful to humans or pets. Crews will spray affected areas on Wednesday, July 30, from 8 p.m. to 11 p.m. In the event of rain, spraying will take place on Thursday, July 31, during those same hours. West Nile Virus remains the leading mosquito-borne disease in the U.S. and is spread to humans through bites from infected mosquitoes. Most cases of West Nile Virus occur during mosquito season, which begins in the spring and goes through the fall. The last reported human case of West Nile Virus in Allegheny County occurred in September 2024. "Generally, the species of mosquitoes that carry West Nile Virus are active from dusk to dawn," said Allegheny County Health Department Vector Control Specialist Nicholas Baldauf. "To deter mosquito bites, we encourage people to use insect repellent on exposed skin or to wear long sleeves and pants. Both methods are effective at reducing or eliminating the possibility of getting a mosquito bite." People who are infected with West Nile Virus usually do not feel sick, and only one in five infected will develop symptoms such as fever, headache, body aches, joint pain, vomiting, diarrhea, or rash. There are no vaccines to prevent or medications to treat West Nile Virus. Residents who believe they or someone they know might have contracted West Nile Virus should contact a health care professional for an official evaluation and diagnosis. "Mosquitoes can breed in as little as a half-inch of stagnant water, so residents should pay close attention to potential breeding sites like stagnant water in tires, unused swimming pools, buckets, corrugated piping, and clogged gutters," Baldauf added.
CBS News
2 days ago
- Health
- CBS News
West Nile virus reported in western Wisconsin resident, health officials say
A resident of Barron County, Wisconsin, has contracted West Nile virus, the first reported case in the state in 2025. The Wisconsin Department of Health Services reported the case on Monday, though details about the resident's condition weren't released. According to state health officials, mosquitoes collected in Milwaukee and Lafayette counties also tested positive for the virus. "The first detections of West Nile virus this year are a reminder to take steps to prevent mosquito bites and possible disease," Paula Tran, state health officer and administrator of the Division of Public Health with the DHS, said. Health officials recommend the following steps to avoid mosquito bites: Mosquitoes in all seven counties of the Twin Cities metro have already tested positive for the virus this year, which the Metropolitan Mosquito Control District said is earlier than usual. The Centers for Disease Control and Prevention says one in five people who are infected will develop a fever and other minor symptoms, and one in around 150 people will develop a severe illness. Note: The video above originally aired July 3, 2025.
Fox News
4 days ago
- Health
- Fox News
Health officials alarmed by unprecedented July spike in West Nile-infected mosquitoes in 2 major cities
Mosquitoes carrying the West Nile virus have reached one of the highest numbers ever recorded in Minnesota during the month of July, and authorities caution citizens to stay inside at dusk and dawn. The blood-sucking bugs in all seven counties of the Minneapolis-Saint Paul metropolitan area tested positive for the disease, according to the Metropolitan Mosquito Control District (MMCD). MMCD ecologists processed nearly 200 mosquito pools and found Culex tarsalis mosquitoes, the species most blamed for spreading the West Nile virus, were "active in some of the highest numbers" ever recorded, according to FOX 9 Minneapolis-St. Paul. Of 133 pools tested, 34 tested positive for the virus, showing a rate of more than 25% positivity, MMCD reported. The rate is one of the highest recorded in the month of July, more in line with numbers seen in late August, when mosquito populations wind down. Positive West Nile virus samples were also found in mosquitoes in other states, including Georgia, where they were confirmed in three different areas of Atlanta. Though the city is working on coordinating insect control, officials asked residents near affected areas to protect themselves from bites and eliminate standing water to prevent mosquito breeding. The West Nile virus is a mosquito-borne disease that can cause encephalitis, or inflammation of the brain, according to the Minnesota Department of Health (MDH). Originating between mosquitoes and birds in Africa and Europe, the virus spread to the U.S. in 1999 when an outbreak in New York sent nearly 60 people to the hospital over two months. Most of the patients had clinical signs of brain swelling, and seven patients died, according to a report from the National Institutes of Health. While the disease can be more detrimental to older patients and those with muscle weakness, MDH officials said most people bitten by infected mosquitoes experience either mild symptoms or none at all.
