West Nile Virus: What you can do

by Maeve Sowles

West Nile virus is coming to the west coast, and we will need to learn to live with it. West Nile virus is a bird disease which has killed thousands of birds as it has made its way across the United States since 1999. Although a bird disease, other animals including humans can become ill if bitten by a mosquito carrying the virus. West Nile virus illness in humans is rare, but we need to reduce the chance that we might become infected. (Around our property we have bird boxes and bat boxes, so I am hopeful that our insect-eating bird residents can help reduce the numbers of mosquitos in our area.) By following some basic guidelines put out by the Centers for Disease Control and by Lane County Public Health Department, we can protect ourselves and also reduce the population of mosquitos around our homes. I hope we can also reduce bird deaths by these simple actions.

Source reduction
Adult mosquitos lay eggs in standing, stagnant water. The eggs hatch and larvae mature in seven to ten days. Interrupting the mosquito reproductive cycle can be done by emptying and flushing containers holding water once per week. This would include potted plants, water troughs, buckets, bird baths and other items around our homes that might be mosquito breeding areas. Rain gutters should be cleaned of leaves which will hold water and create a rich, stagnant environment where mosquitos can breed. Empty and remove old tires and pick up litter and other debris that could harbor mosquito larvae. This is the ultimate in spring cleaning.

Mosquito avoidance
The goal of this approach is to keep blood-sucking arthropods from biting you. Repair and replace screens, keep doors and windows closed. Stay inside at dawn and dusk when mosquitos are most active. If you are outdoors, wear long sleeves and long pants. Use mosquito repellant, but remember that these topical applications do not stay active indefinitely and may need to be reapplied. “Natural” mosquito repellants include citronella and eucalyptus. These are chemicals also, so can cause adverse symptoms in some people and should be washed off after use. These items are effective, but will not last as long as DEET (N,N-diethyl-meta-toluamide). This chemical can cause eye irritation, skin blisters, headaches, irritability, loss of consciousness, and seizures in sensitive individuals. Do not spray repellant on your skin underneath clothing. Caution is advised in using DEET on children and it should be washed off after use. Wash your hands after application so that you do not accidentally ingest it or wipe your eyes. Mosquito nets are another physical barrier used with success. There are mosquito net covers designed for hikers and workers. Please remember that spraying to kill mosquitos will kill other, beneficial insects as well, and poisoned insects will be eaten by birds. The insecticides used to spray for adult mosquitos are toxic to fish and, ultimately, to all of us.

Reporting dead birds
This will be handled by the Lane County Health Department at 682-4041. A "phone nurse" will handle these calls. Only fresh dead birds will be tested for West Nile virus, and only a limited number. If the bird has signs of injury, it will not be tested. The Health Department will screen the calls to be sure only birds suspected of West Nile virus disease will be tested. Do not handle any dead birds with your hands. Use a plastic bag, gloves or shovel and always wash afterwards. This advice should apply to any dead or injured wildlife.

• Lane County Public Health
• Centers for Disease Control
• Audubon.org
• DEET-free insect repellents