Early symptoms of West Nile virus

The early symptoms of West Nile virus may appear 1-14 days after exposure; more specifically, a mild infection known as West Nile Fever.

West Nile fever symptoms include:

·         Abdominal pain.

·         Diarrhea.

·         Fever.

·         Headache.

·         Appetite loss.

·         Muscle aches.

·         Joint pain.

·         Nausea.

·         Skin rash.

·         Sore throat.

·         Enlarged lymph nodes.

·         Vomiting.

·         Fatigue.

·         Back pain.

·         Eye pain.

These symptoms may last anywhere from 3 to 6 days to a month. However, about 70%-80% of people who are infected with the West Nile Virus do not show any symptoms at all. When symptoms do occur, they resemble those of other viral infections. Several tests can help make a diagnosis, though.

Tests, exams and diagnosis

·         Serology test

Checks a blood or cerebrospinal fluid (CSF) sample for antibodies against the West Nile virus.

·         Lumbar puncture

Also known as spinal tap, it analyzes CSF to check for Wes Nile-related meningitis.

·         Brain tests

CT scan, EEG or MRI.

·         Complete blood count



Very rarely (less than 1% of infected people) the West Nile virus may cause a severe neurological infection, including encephalitis, meningitis, meningoencephalitis, or poliomyelitis. Symptoms of such an infection include:

·         High fever.

·         Severe headache.

·         Stiff neck.

·         Disorientation.

·         Confusion.

·         Stupor or coma.

·         Tremors.

·         Muscle jerking.

·         Loss of coordination.

·         Convulsions.

·         Pain.

·         Partial paralysis.

·         Sudden muscle weakness.

There is no specific treatment for the West Nile virus – especially not antibiotics, since this is a viral infection; that is, not caused by bacteria. Over-the-counter pain medicines such as aspirin may decrease fever and alleviate certain symptoms. Serious cases may require hospitalization to receive intravenous fluids, pain medication, nursing care, and other supportive treatments. Treatment can help prevent the rare but possible complications from this condition, such as brain damage, permanent muscle weakness, and death. However, the majority of people with West Nile virus recover satisfactorily, even without treatment – except those with severe infections that lead to encephalitis or meningitis, 10% of which pass away.

In the U.S. risk factors for contracting West Nile virus include:

Spending time outside®between July-September®in Midwestern and Southwestern states


Additionally, certain individuals have a higher risk of developing a severe infection, namely:

·         People with HIV or who have recently undergone organ transplants or chemotherapy and thus have weakened immune systems.

·         Very young and elderly people.

·         Pregnant women.

The virus is carried by mosquitoes that have fed on infected birds. These mosquitoes – which breed in standing water – can then pass the virus to other birds, as well as to mammals both of the animal and human kind. There is no vaccine against the West Nile virus, but there are preventive measures such as:

·         Using insect repellent made with DEET.

·         Wearing long sleeves, long pants, and socks.

·         Draining standing water pools like trash bins ad plant saucers.

·         Unclogging roof gutters.

·         Changing birdbath water at least once a week.

·         Removing old tires and unused containers that might hold water.

·         Avoiding unnecessary outdoor activity during peak mosquito-biting hours, particularly at dawn, dusk, and early evening.

The West Nile Virus is not transmitted through casual person-to-person contact, handling live or dead infected birds, or consuming infected birds or animals.

Related Read:

Early symptoms of dengue