First Human Infection Of West Nile Virus Seen In Los Angeles County

Health authorities report two cases of West Nile Virus infection in the San Fernando Valley region as the U.S. enters the peak mosquito season.

One of the cases involved an older adult hospitalized in early July due to the neuroinvasive disease. The patient did not have any underlying ailment, the Los Angeles County Department of Public Health said in a news release.

The agency stated they detected the other case in late July from a person who was a healthy blood donor, adding that the blood units from this donor were immediately discarded. "West Nile virus continues to be a serious health threat to residents in Los Angeles County," local health officer Dr. Muntu Davis stated in a press release.

He also encouraged residents to cover, clean, or discard items that may hold water and breed Culex mosquito species, whether such items are found inside or outside of the home. Dr. Davis said this is very important as many homeowners spend most of their time at home nowadays.

He also reminded everyone that it is peak mosquito season in Los Angeles County, which is why residents must ensure they get proper protection from mosquitoes, especially those that carry diseases, by using EPA-approved mosquito repellent products. Mosquito season in Los Angeles County begins in June and culminates in November.

Health officials reported over 10,000 residents in Los Angeles comes down with a West Nile virus infection annually, but these are neither reported nor identified as caused by the virus. Most of those infected report experiencing only mild symptoms such as feeling feverish, skin rash, and fatigue. In rare cases, the infection may affect the spinal cord and the brain, often leading to encephalitis, meningitis and paralysis.

Even if many of those infected with the West Nile virus experience only mild symptoms, recovery can take months or even years. The Los Angeles County Department of Public Health, in their news release, claimed one study showed that one year after infection, around 50% of those infected continue to experience cognitive and physical deficiency like memory loss, fatigue and walking difficulties.

At present, there are no vaccines to prevent West Nile virus infection in people. The best protection against West Nile virus infection is for people to observe precautionary health measures, the Los Angeles County Department of Public Health stated. This includes ensuring windows and doors have tight-fitting screens so mosquitoes cannot enter the home's interiors. Aside from using EPA-approved mosquito repellents, wearing pants and long-sleeved clothes whenever outside can also help.

The health department also advises that homeowners should check, at least once a week, if there are items outside or inside their house that hold water, since mosquitoes lay their eggs in clear, standing water. These include birdbaths, flowerpots, saucers and other types of containers. Buckets and rain barrels must have proper lid covers. For those who have swimming pools or spas, even the tiniest amount of water must be drained from its covers. Items like old car tires and children's toys in the yard or patio must be properly discarded.