Mosquito season is upon us again. These pesky insects, out in force already, can be carriers of West Nile virus, a potentially serious illness. Mosquitoes become infected by biting (feeding on) an infected bird. An infected mosquito can then spread the virus to animals it bites, such as other birds and horses, as well as humans. The usual culprits are mosquitoes of the Culex species.
“About 1 in every 150 people infected with West Nile virus will develop symptoms of severe illness that can last several weeks and may cause permanent neurological deficits,” said Michele Bever, Executive Director, South Heartland District Health Department (SHDHD). The symptoms of severe illness can include high fever, headache, neck stiffness, disorientation, coma, tremors, convulsions, muscle weakness, numbness and paralysis.
Approximately 20% of people infected with West Nile virus experience milder symptoms consisting of fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach, and back. These symptoms can last from just a few days to several weeks.
Most people (4 out of 5) who are infected with West Nile virus do not show any symptoms at all, but there is no way to know ahead of time whether you will be one of these lucky ones. Most people with mild symptoms recover on their own but for others the symptoms may last for weeks or months. More severe cases of West Nile illness may require hospitalization to receive supportive treatment.
Currently there is no vaccine available for humans, but scientists are working on it and hope that one might be available in the next few years. Most veterinarians in our region offer West Nile virus vaccinations for horses. Data provided by Nebraska DHHS support that the best way to prevent illness in horses is for them to be vaccinated. For humans, the best prevention is to avoid mosquito bites and to clean out the mosquitoes and mosquito breeding areas from places where you work and live.
The Centers for Disease Control and Prevention (CDC) suggests several ways to prevent mosquito bites. When you are outdoors, be sure to wear mosquito repellent containing DEET, or other insect repellent that is registered with the Environmental Protection Agency (EPA), and follow the directions on the package for proper use. Between dusk and dawn, when mosquitoes are most active, wear long sleeves and pants or consider staying indoors. In addition, keep mosquitoes out of your house by installing screens or ensuring that the screens on your windows and doors are in good shape.
Additional prevention tips include ways to reduce the number of mosquitoes and mosquito breeding areas where you live, work, and recreate. Empty standing water from anything that might serve as a container: flower pots, gutters, tires, buckets, etc. Drill a drainage hole in tire swings and frequently (at least weekly) empty and replace the water in pet bowls, children’s wading pools, or bird baths.
You can also help your community monitor West Nile virus by reporting dead birds to your local health department. Dead birds may be a sign that West Nile virus is circulating between the birds and the mosquitoes in a particular area. Starting June 1, the South Heartland District Health Department (Adams, Clay, Nuckolls and Webster Counties) will accept freshly dead, adult birds. Birds belonging to the corvidae family including Jays, Magpies, Crows and Ravens will be sent to our state lab for testing. To be tested, the bird must be collected and frozen for shipment within 24 hours of death. If you find a dead bird of the corvidae family that could be tested, please contact the Department at 402-462-6211 or toll free at 1-877-238-7595.
Last season (2014), 142 Nebraskans were reported to have West Nile illness. Unfortunately, there were seven deaths in Nebraska associated with the illness last year. South Heartland District (Adams, Clay, Nuckolls, and Webster counties) has received reports of less than twenty cases each year over the past five years. “The numbers of West Nile virus human cases seem to vary year to year” said Jessica Warner, SHDHD Disease Surveillance Coordinator, “so we should all take precautions each year as if the current year will be one with increased illness due to the virus.”
Increased community efforts to reduce standing water, more people taking precautions to protect themselves, and annual variations in numbers and types of mosquitoes, are all factors which could contribute to the decrease in cases.
Remember these four “D”s of effective prevention: Dusk to Dawn (avoid outdoor activity or take extra care to protect yourself), Dress Appropriately (long sleeves, pants, socks when outside during the peak hours and locations of mosquito activity), DEET (in your mosquito repellent), Drain (any standing water). Remind your family members and friends of these easy steps to “Fight the Bite”.