What to know about West Nile virus

News about the West Nile virus is everywhere, and for good reason.

According to the U.S. Centers for Disease Control and Prevention, the number of reported cases this year is on pace to be the highest since the first time the virus was detected in the United States in 1999. At least 47 states have seen some sort of activity, and nearly half of all infections have occurred in Texas.

West Nile virus is spread by mosquitoes that pick up the virus when they bite infected birds. These infected mosquitoes then spread the virus to humans. This year, unseasonably hot weather combined with fluctuations between rainfall and drought have helped create the perfect recipe for an outbreak.

“There are many factors that influence the transmission of infections that involve insects and humans,” says John Midturi, D.O., M.P.H., assistant professor of internal medicine at the Texas A&M Health Science Center College of Medicine and interim division director of infectious diseases at Scott & White in Temple. “There are factors that increase the mosquito populations such as rain and heat and conditions that increase interaction between mosquitoes and humans such as summertime evening exposures.”

Most people do not realize they have West Nile because the virus infection usually causes few or no symptoms. However, in rare cases, the illness can lead to encephalitis or meningitis.

The usual incubation period from infection to the development of symptoms is from three days to two weeks. If you have been bitten by mosquitoes, watch for fever, headaches, body aches, eye pain, skin rashes, exhaustion, lack of appetite, nausea, vomiting and/or swollen lymph nodes.

Unfortunately, there is no specific treatment for West Nile virus. If you experience any of these or more serious symptoms, consult a doctor immediately.

“The management for serious cases includes supportive care, meaning medical assistance in fluid balance and possibly ventilator support,” Dr. Midturi said. “Mild cases should recover with minimal medical intervention.”

The best way to prevent contracting the virus is to follow the four “Ds”:

• DEET – Use insect repellant with this ingredient.
• Dress – Wear long sleeves and long pants outdoors.
• Dusk and Dawn – Avoid being outside between dusk and dawn (when mosquitoes are most active).
• Drain – Remove and drain standing water.

“The most important measure is bite avoidance,” Dr. Mituri said. “If you don’t get bit by mosquitoes carrying West Nile, malaria or other diseases, you won’t contract those diseases.”

More information about West Nile virus is online at www.cdc.gov/westnile.