Signs Of West Nile Virus In Children, Treatment & Prevention

check_icon Research-backed

Image: Shutterstock


West Nile fever in children occurs due to the West Nile virus or WNV. The virus is transmitted through the bite of mosquitoes. The vector-borne illness is usually uncommon in children and may only cause mild symptoms if it occurs. However, the fever may cause neuro-invasive disease in a few cases (1).

The West Nile fever may be a rare infection, but delayed identification paired with improper management may lead to complications. This post elaborates on the symptoms, risk factors, complications, treatment, and prevention of West Nile fever in children.

Risks And Causes Of West Nile Virus Infection In Children

West Nile virus infection is caused by the bite of an infected female mosquito. Female Culex mosquitoes are the principal vectors of the West Nile virus.

A child is at high risk of getting exposed to the virus during the summer months. Children with weakened immune systems can get severe WNV infection (2) (3). The West Nile virus belongs to a group of flaviviruses commonly found in Europe, Australia, the Middle East, Africa, and West Asia. Yellow fever, dengue, St. Louis encephalitis, and Japanese encephalitis are also examples of infections caused by flaviviruses (4).

How Is WNV Spread?

West Nile virus is transmitted to children from the bite of an infected mosquito. The mosquitoes, in turn, may get the virus from infected birds (5).

In extremely rare cases, the West Nile virus can be transmitted through (5)

  • Organ transplant
  • Blood transfusion
  • Mother to baby during pregnancy, delivery, or breastfeeding (vertical transmission)
  • Exposure to the virus in laboratories

West Nile viruses are not spread from touching animals, handling dead or infected birds, coughing or sneezing, or eating infected animals or birds (5). However, safety precautions are recommended to avoid various other health hazards.

Signs And Symptoms Of WNV Infection

Mild, flu-like symptoms for a few days may be seen in children with West Nile virus infection. These symptoms often appear three to 14 days after the child contracts the virus. The signs and symptoms may vary in each child. However, nearly 20% of people with WNV infection develop West Nile fever (6).

The following are some common signs and symptoms of West Nile virus infection (7).

  • Fever (febrile illness)
  • Skin rashes on the trunk
  • Body aches and joint pain
  • Headache
  • Vomiting
  • Diarrhea

One out of 150 cases of WNV infection can result in severe illness since the virus may cross the blood-brain barrier. This may result in brain and brain membrane inflammation and cause the more severe forms of the disease, including West Nile meningitis, West Nile encephalitis, and West Nile meningoencephalitis. Brain involvement can occur at any age, but it is not common in children (6).

The following signs and symptoms may indicate brain infection due to the West Nile virus (5).

  • High fever
  • Stiff neck
  • Headache
  • Disorientation
  • Stupor—a state of extreme lethargy, altered consciousness, and decreased reaction to external stimuli
  • Muscle weakness
  • Tremors
  • Convulsions
  • Paralysis
  • Coma

You may seek medical care for an exact diagnosis since these symptoms can also be seen in other medical conditions. Some children can be asymptomatic too.

Complications Of West Nile Virus Infection

Complications arising from West Nile virus infection are rare in children. Most children with febrile illness due to the West Nile virus recover completely.

In some cases, tiredness and weakness may last for weeks and months after the infection. And in very rare cases, brain involvement can lead to coma, paralysis, or death (8).

Inflammation of the brain tissue (West Nile Encephalitis), inflammation of the membranes lining the brain and spinal cord (West Nile meningitis), or both combined (West Nile meningoencephalitis) is often associated with poor outcomes.

Diagnosis Of West Nile Fever In Children

The child’s health history and symptoms can be suggestive of the diagnosis in most cases. The following tests are also ordered to confirm the presence of the West Nile virus in the body (3)(9).

  • Blood tests: An increased level of antibodies against the disease can be determined on blood tests. Viruses can also be isolated by cell culture, and RT-PCR tests also help detect West Nile virus in the body.
  • Lumbar puncture (spinal tap): Cerebrospinal fluid (CSF) is collected through lumbar puncture using a fine needle. Analysis of cerebrospinal fluid can help identify brain involvement.
  • CT scan: This may help visualize the brain tissue to identify any pathologies.
  • MRI scan: This may give a better view of brain parenchyma (brain tissue) than a CT scan and help detect brain inflammation in the case of West Nile encephalitis or meningitis.
  • Electroencephalograms (EEG): This helps diagnose brain seizures that are not visible from the outside.

Doctors may also ask about the child’s exposure to mosquitos. Additional tests are often ordered depending on the symptoms to exclude the diagnosis of certain conditions.

Treatment For WNV Infection

There is no specific treatment for West Nile virus infection. Symptomatic treatments are provided to relieve symptoms such as fever and headaches. Acetaminophen (Tylenol) is often prescribed for mild cases.

Children with brain inflammation require hospitalization and supportive therapies. Blood pressure, breathing, and heart rate are monitored in children with meningitis or encephalitis. Corticosteroids are given to reduce brain inflammation, while anticonvulsants (anti-seizure) medications are administered to control seizures. Most children recover well with appropriate supportive care (9).

How To Prevent WNV Infection?

There is no vaccine to prevent West Nile disease. However, protecting the child from mosquito bites can prevent WNV infection. The following tips may help avoid mosquito bites(10).

  1. Use mosquito repellents that are safe and EPA-registered for children according to their age. Always read the labels of the insect repellants, and do not use them on the hands, mouth, wounds, or near the eyes. Ensure that the repellant contains active ingredients such as DEET. Apply a sunscreen or moisturizer before using an insect repellant.
  1. Wear long sleeves and full pants. Use thick clothing since mosquitoes may bite through thin clothing.
  1. Use mosquito nets on bedding, windows, and doors. Repair or cover any holes in the screens or walls to prevent mosquitoes from entering the house. Use mosquito nets while sleeping outdoors during camping or other activities, and cover strollers and other baby carriers with mosquito nets to prevent bites in young children.
  1. Use air conditioning instead of opening the windows, if possible, especially if you reside in areas with When traveling to endemic areas of mosquito-borne diseases, choose hotels or stays with air conditioning or window and door screens.
  1. Avoid stagnant water near the houses, and ensure water does not accumulate in indoor plant saucers.

West Nile fever in children can be prevented by effective mosquito prevention, and seeking early medical care can prevent complications of West Nile virus infection. Although there is no specific cure for this illness, appropriate supportive care may help the child recover fully. Mosquito prevention can also help avoid other mosquito-borne illnesses such as dengue fever and yellow fever.

Key Pointers

  • The bite of infected female Culex mosquitoes can cause WNV infection in children.
  • Because the virus may pass the blood-brain barrier, one out of every 150 instances of WNV infection can result in serious diseases such as West Nile meningitis.
  • High fever, headaches, stupor, paralysis, coma, and other symptoms may suggest a WNV infection in the brain, but this is unusual in children.
  • Children with brain inflammation caused by WNV infection require hospitalization and supportive therapy.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
The following two tabs change content below.

Maria Carmela Villania-Mamauag

Maria Carmela Villania-Mamauag is a board certified diplomate of the Philippine Pediatric Society with a degree of Doctor of Medicine from Our Lady of Fatima University, Valenzuela City and a Bachelor in Science in Psychology from Saint Louis University, Baguio City which was augmented by a year of Bachelor in Science in Family Life and Child development at the University... more

Dr Bisny T. Joseph

Dr. Bisny T. Joseph is a Georgian Board-certified physician. She has completed her professional graduate degree as a medical doctor from Tbilisi State Medical University, Georgia. She has 3+ years of experience in various sectors of medical affairs as a physician, medical reviewer, medical writer, health coach, and Q&A expert. Her interest in digital medical education and patient education made... more