This week, the Louisiana Department of Health and Hospitals (DHH) confirmed nine new cases of West Nile virus, of which five were neuroinvasive disease cases, bringing this year’s total to 61 reported infections. Louisiana continues to have the nation’s second highest number of West Nile virus neuroinvasive disease cases.

West Nile virus
Culex quinquefasciatus
Image/CDC

This week’s new infections include five neuroinvasive disease cases, all in East Baton Rouge Parish. There were four new cases of West Nile fever; Ascension (1), Caddo (1) and East Baton Rouge (2) parishes, and no new asymptomatic cases. A previously reported asymptomatic case in Caddo Parish has been upgraded to neuroinvasive disease.

“If you’re going to be outside this Labor Day weekend, take time to protect yourself from mosquitoes,” said DHH State Epidemiologist Dr. Raoult Ratard. “Protecting yourself is very simple and it could spare you from getting this disease.”

Humans contract West Nile when they are bitten by mosquitoes infected with the virus. When people are infected with West Nile, the virus will affect them one of three ways. West Nile neuroinvasive disease is the most serious type, infecting the brain and spinal cord. Neuroinvasive disease can lead to death, paralysis and brain damage. The milder viral infection is West Nile fever, in which people experience flu-like symptoms. The majority of people who contract West Nile will be asymptomatic, which means they show no symptoms. These cases are typically detected through blood donations or in the course of other routine medical tests.

About 90 percent of all cases are asymptomatic, while about 10 percent will develop West Nile fever. Only a very small number of infected individuals will show the serious symptoms associated with the neuroinvasive disease. Residents who are 65 years old and older are at higher risk for complications, but everyone is at risk for infection.

As of Aug. 26, the Centers for Disease Control and Prevention reported 297 West Nile virus cases nationally, including 12 deaths.

In addition, the DHH says there were no new cases of chikungunya fever or dengue fever in Louisiana. So far this year, there have been 10 cases of chikungunya fever and one case of dengue fever.