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West Nile Virus

Overview

This is a viral infection you get from a mosquito bite. For most people, it's not serious or dangerous. You can get it and not even know you have it. But for some people, it can be life-threatening.

Causes

West Nile virus is carried by birds. When a mosquito bites an infected bird and then bites you, the virus can get into your body. Most cases of West Nile virus happen when the weather is warm. That's when mosquitoes are most active.

Symptoms

If you get an infection, you may never show any symptoms. If you do have symptoms, they appear two days to two weeks after the bite. You may have a mild fever and a mild headache. You may have body aches, vomiting, diarrhea, fatigue and skin rash. Or, your symptoms may be more serious. You may develop a high fever, severe headache, weakness and confusion. You can have seizures and tremors. If you have these or other severe symptoms, seek help immediately. This is a medical emergency.

Treatment

Treatment options are based on your needs. Mild cases may get better on their own with no treatment. Or, you may need pain relievers to help ease symptoms. If you've lost fluids, an IV may help. Some people need to be hospitalized.

Prevention

You can reduce your risk by staying away from mosquitoes. So stay inside when mosquitoes are active. Cover your skin and use mosquito repellent. Empty, clean and cover or dispose of outdoor sources of standing water like empty containers, flower pots, birdbaths, toy pools and planters, because that's where mosquitoes lay eggs. These simple precautions greatly reduce your risk for West Nile virus.

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.