West Nile virus can be prevented by using insect repellent and getting rid of standing water sources, such as wading pools and planters. (photo by Getty/courtesy of Cedars-Sinai)

West Nile virus, a rare and serious disease that is transmitted through mosquitos, has made its way to Los Angeles and Orange counties, with several cases now confirmed throughout the region.

“Although the virus primarily affects birds, it gets transmitted to humans if a mosquito bites an infected bird and then bites a human,” said Dr. Jonathan Grein, director of Hospital Epidemiology at Cedars-Sinai Medical Center. “Contracting a virus found in birds sounds like science fiction, but that’s exactly what West Nile virus is.”

While a single mosquito bite can be enough to transmit the infection, Grein said most people are not at risk following a single mosquito bite. In fact, Grein said, only a small number of people will develop the virus’ most severe symptoms.

“Most people infected with West Vile virus will experience symptoms similar to the flu, including fever, headaches, muscle aches and fatigue,” Grein said. “Although some people may develop a rash, abdominal pain, nausea or diarrhea, most experience only mild symptoms that last several days to weeks and resolve on their own.”

Only about one in 150 people who contract West Nile virus will require hospitalization for severe symptoms, which can include coma, neck stiffness, high fever, paralysis and infection of the brain called encephalitis.

West Nile virus can occur in anyone, although certain people – including adults over the age of 50 and those with a weak immune system, such as patients on immune-suppressing medications like chemotherapy – are at higher risk of developing the severe disease.

“It’s also important to note that West Nile virus cannot be spread through touching, kissing or sharing utensils,” Grein said. “The disease can only be transmitted through mosquito bites.”

There is no vaccine available to prevent West Nile virus, so Grein said residents should protect themselves by following guidelines set by the Centers for Disease Control and Prevention, including using insect repellant containing DEET; wearing long-sleeved shirts and pants containing DEET, when possible; staying indoors at dawn, dusk and early evening; and removing standing water sources.

“These standing water sources can include things like containers, planters and animal water bowls,” said Grein. “It’s important to take inventory of your outside area and remove any unnecessary items. This quick but impactful step may prevent the spread of West Nile virus.”

Cedars-Sinai is located at 8700 Beverly Blvd. For information, visit cedars-sinai.org/health-library/diseases-and-conditions/w/west-nile-virus-1.html.