An Introduction to West Nile Virus
West Nile virus spreads most frequently in the summer, especially from June to September. About 70-80% of infected people never feel any symptoms. About 20% of infected people may experience symptoms such as fever, headache, vomiting, and diarrhea, which usually go away quickly.
Some people may feel fatigued for several months after the initial infection. Fewer than 1 percent of people infected with West Nile virus develop severe symptoms such as meningitis or encephalitis. And of these severe cases, fewer than 10 percent are fatal.
West Nile virus is a virus spread by mosquitoes. Mosquito bites can cause serious illness when they are carrying the West Nile Virus (WNV). Mosquitoes transmit the virus by biting infected birds, which then transmit it to humans.
However, not everyone bitten by an infected mosquito will fall ill. The virus is more dangerous for people over 60 years of age and those with weakened immune systems. With prompt treatment, most people recover well from West Nile meningitis.
Symptoms
If you are infected with West Nile Virus, you will usually notice symptoms within 3 to 14 days of being bitten by a mosquito. Symptoms can be mild or severe.
Severe symptoms can include:
- High fever
- Confusion
- Seizures
- Muscle weakness
- Visual impairment
- Numbness
- Paralysis
- Coma
Severe cases can last for weeks and in rare cases can cause permanent brain damage.
Mild symptoms may include:
- Fever
- Headache
- Body aches
- Nausea
- Vomiting
- Swollen lymph nodes
- Rashes on the chest, stomach, or back
Mild cases may not last long and may be confused with the flu.
Understanding the causes of West Nile virus
West Nile virus is usually transmitted by mosquito bites. Mosquitoes transmit the virus by biting infected birds, then pass it on to humans and animals through the bite.
Rarely, the virus can be spread through blood transfusions, organ transplants, breastfeeding, and pregnancy. However, it cannot be spread by kissing or touching another person.
What are the Risk Factors?
People who are bitten by mosquitoes can become infected with West Nile meningitis, but severe or life-threatening symptoms are rare, affecting less than 1 percent of people.
- Age: Older people, especially those over 60, are more likely to develop severe symptoms.
- Health conditions that increase risk: Kidney problems, Diabetes, High blood pressure, Cancer, Weakened immune system
Diagnosing infection
Doctors usually diagnose West Nile virus with a simple blood test to check for the virus or antibodies in your blood. If you have severe symptoms affecting your brain, your doctor may do a lumbar puncture, in which a needle is used to take a sample of fluid from your spine.
An increased number of white blood cells in this fluid may indicate an infection. MRIs and other scans can also help detect inflammation and swelling in the brain.
Treatment of west nile fever virus
There is no treatment for West Nile virus, because it is caused by a virus. However, symptoms such as muscle aches and headaches can be relieved with over-the-counter painkillers such as ibuprofen or aspirin.
If you have severe symptoms such as brain swelling, your doctor may give you fluids through an IV or medication to reduce the risk of infection. Researchers are studying interferon therapy for West Nile virus.
This treatment uses substances from the immune system to treat encephalitis caused by the virus. Although more research is needed, early studies show these treatments are promising.
Other treatments being studied for West Nile Virus encephalitis include:
- Intravenous polyclonal immunoglobulin (IGIV)
- Recombinant humanized monoclonal antibody against WNV (MGAWN1)
- Corticosteroids
Your doctor may recommend these treatments. Consult your doctor if you have severe or life-threatening symptoms of West Nile Virus encephalitis.
What measures can you take to prevent WNV?
You can reduce your risk of contracting West Nile virus by following these steps when outdoors:
- Cover your skin by wearing long-sleeved shirts, pants, and socks.
- Wear insect repellent on your skin.
- Remove standing water around your home, as it attracts mosquitoes.
- Install mosquito-proof screens on your windows and doors.
- Use mosquito netting around playpens and strollers to protect children from mosquito bites.
- Mosquito bites are most common in late August and early September.
- The risk is lower during cold weather because mosquitoes cannot survive in cold weather.
- If you find a dead bird, report it to your local health department, but do not touch it.
- Dead birds can transmit West Nile virus to mosquitoes, which can infect people with just one mosquito bite.
If the virus is detected in the region, health officials may step up efforts to control west nile fever in India and stop the spread of the virus.
Sum up
There is a vaccine to prevent West Nile virus for horses, but not yet for humans. If you are infected with WNV, symptomatic treatment is important for your recovery, especially if you are severely ill.
If you experience any of the symptoms listed above, seek medical attention, especially if you have been recently bitten by a mosquito or have been in a mosquito-prone area. Most people recover fully and quickly from WNV infection.
Prompt and regular treatment is key to keeping symptoms under control, especially for older adults and those with certain health problems that put them at higher risk.
