From the Guidelines
West Nile virus typically causes no symptoms in about 80% of infected people, but when symptoms do occur, they can range from mild to severe, including fever, headache, body aches, joint pain, vomiting, diarrhea, and sometimes a skin rash, as well as more severe neurological effects such as high fever, severe headache, neck stiffness, disorientation, coma, tremors, seizures, muscle weakness, vision loss, numbness, and paralysis 1. The symptoms of West Nile virus can be divided into two main categories: mild and severe. Mild symptoms, which occur in about 20% of infected people, include:
- Fever
- Headache
- Body aches
- Joint pain
- Vomiting
- Diarrhea
- Skin rash on the chest, stomach, and back These mild symptoms typically last for a few days to a week. More severe symptoms, which affect about 1 in 150 infected people, can include:
- High fever
- Severe headache
- Neck stiffness
- Disorientation
- Coma
- Tremors
- Seizures
- Muscle weakness
- Vision loss
- Numbness
- Paralysis These neurological effects may be permanent and can appear within 3-14 days after infection, requiring immediate medical attention 1. It is essential to note that people over 60 years old and those with certain medical conditions, such as cancer, diabetes, hypertension, or organ transplants, are at higher risk for severe illness. There is no specific treatment for West Nile virus infection; care is supportive, focusing on managing symptoms. Prevention involves avoiding mosquito bites through repellents, protective clothing, and eliminating standing water where mosquitoes breed.
From the Research
Symptoms of West Nile Virus
The symptoms of West Nile virus can vary from mild to severe, and in some cases, can be life-threatening. Some of the common symptoms include:
- Fever
- Headache
- Myalgias (muscle pain)
- Meningitis (inflammation of the membranes surrounding the brain and spinal cord)
- Encephalitis (inflammation of the brain)
- Acute flaccid paralysis (a condition characterized by weakness or paralysis of the muscles) 2, 3, 4, 5, 6
Severe Symptoms
In severe cases, West Nile virus can cause:
- High fever
- Neck stiffness
- Disorientation
- Tremors
- Seizures
- Paralysis
- Respiratory failure
- Bladder dysfunction 3, 4, 6
Risk Factors
Certain individuals are at a higher risk of developing severe symptoms, including:
Diagnosis and Treatment
Diagnosis of West Nile virus is typically made through laboratory tests, such as testing for IgM antibody to West Nile virus in serum or cerebrospinal fluid 2. Treatment is usually supportive, and there is no specific antiviral treatment for West Nile virus 3, 4. Prevention measures, such as avoiding mosquito bites and using mosquito repellents, are essential for reducing the incidence of the disease 2, 5.