What's New 

Author: William M. Wiencke, M.D.
Clinic: Como/Roseville Clinic

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     With the coming of spring, we will start seeing mosquitoes again, and with the mosquito, we will begin hearing again about the West Nile virus that received so much publicity last summer. This is a virus that is carried by birds and some animals, and then can be spread to humans by mosquitoes. According to state health department statistics there were only 46 laboratory proven cases in Minnesota last year and none in Ramsey County, so the illness is not common in our area. Most people exposed to the virus develop no symptoms, 20 percent of people develop mild symptoms called West Nile fever, and only one in 150 will develop the more severe form of the disease, West Nile viral encephalitis. Symptoms of the mild disease are fatigue, headache, upset stomach, and, occasionally, skin rash. More severe disease will have muscle weakness, high fever, and disorientation, and can progress to coma. [People with impaired immune systems, elderly, and chronically ill often have the more severe forms of the illness.] Treatment for West Nile viral disease is supportive, with medications for fever and discomfort, fluid, good nutrition, and rest. Antibiotics are not effective for this viral infection.

 

While it's not possible to avoid mosquitoes altogether, we can reduce our exposure by using mosquito repellants and avoiding bites by covering skin with clothing and moving indoors in the early morning and evening hours when mosquitoes are more active. It's also a good idea to decrease the mosquito breeding areas around our homes by eliminating areas of standing water.  Mosquito repellents are effective in keeping mosquitoes from biting and are recommended especially if outdoors at dusk or dawn when they are most active. The most effective repellents contain DEET. The percentage of DEET in a product determines the length of time it will repel insects. 23.8% DEET will give about 5 hours of protection and 4.75% works for about 1 ½ hours. DEET is generally considered safe when used according to the directions, but the America Academy of Pediatrics recommends using a concentration of 10% or less on children aged 1-12. For children younger than 2, it's best to check with your Family Physician.