LOS ANGELES (KABC) -- The L.A. County Department of Public Health has identified the first case of human West Nile virus infection in L.A. County for the 2018 season.
A San Gabriel Valley resident was hospitalized in May with the disease, which is spread by the bite of an infected mosquito. It can affect the nervous system and result in meningitis, encephalitis, paralysis and even death.
People over 50 years of age and those with chronic medical problems are at higher risk of severe disease, according to Jeffrey Gunzenhauser, M.D., M.P.H., an L.A. County health officer.
Although more than 10,000 L.A. County residents are infected with the West Nile virus each year, most do not experience any illness or perhaps only mild illness. These cases are neither reported nor even recognized as West Nile virus.
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Public health officials continue to report elevated numbers of West Nile virus cases in L.A. County across the previous five years, at an average of 221 cases per year. More than three quarters of reported cases have had severe disease and approximately 7 percent of patients with severe West Nile virus have died from complications.
Last year's West Nile virus season was the longest season on record, extending until mid-December.
Since mosquitoes spread West Nile, the best precautions include wearing insect repellent along with long sleeves and pants.
Residents are also encouraged to keep door and window screens shut, and to remove any standing water as it's a breeding area for mosquitoes.
West Nile virus confirmed in LA County