West Nile virus affects the central nervous system but symptoms will vary depending on the severity of the illness.

Most people will have no symptoms. Approximately 80% of people (4 out of 5) who are infected will not show any symptoms at all.

Up to 20% of those who become infected will display mild symptoms including fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. Symptoms can last a few days to several weeks.

About one in 150 people infected with West Nile virus will develop a serious illness, with high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and/or paralysis. These symptoms may last several weeks, and neurological effects may be permanent.

The incubation period for West Nile virus is 3 to 14 days and there is no specific treatment. People with mild symptoms such as fever and aches tend to get better on their own. Those who contract the severe form of the illness will be hospitalized.

Pregnant women are not at increased risk of getting West Nile virus.

Insect repellents such as DEET can be used by pregnant women, but you may feel more comfortable with other measures, such as protective clothing and avoiding times and places where mosquitoes are most active. There are no reported adverse effects from the use of repellents containing DEET in pregnant or breastfeeding women.

Pregnant women with symptoms of infection should see a health professional.

Mild cases tend to improve on their own. You do not necessarily need to seek medical attention, though you may choose to do so. You may contact your health professional or call the Saskatchewan HealthLine at 1-877-800-0002.

If you develop symptoms of severe West Nile virus illness (unusually severe headaches or confusion) seek medical attention immediately.