CDC: Current West Nile Outbreak is Fastest Ever

This summer has seen the fastest outbreak of West Nile virus since the mosquito-borne illness first appeared in the United States in 1999, officials from the Centers for Disease Control said Wednesday.

Locally, no one in Placer County has tested positive for the virus, but 20 dead birds and 72 mosquito samples have been found to be carrying West Nile in the county, according to the Placer Mosquito and Vector Control District.

In early August, 22 mosquito samples tested positive for West Nile in one week, all on the western side of Placer County down to the southern border of Roseville, the district reports.

According to Dr. Mary Sorensen, entomologist and laboratory director for the district, that was the most West Nile activity she has seen in one week since 2009, when she started with the district.

“This is the most virus activity we have seen all year  We are very concerned about these results, since some of the infected mosquitoes we’ve found have been very close to residential areas,”  Sorensen said in a news release in August.

Across the country, there have been 1,118 reported illnesses–the most ever reported by the third week of August. Half of the illnesses reported this year are in Texas. 

West Nile virus symptoms may include headache, fever, body aches, vomiting, nausea, swollen lymph glands, and skin rash on the chest, stomach and back.

Approximately 80 percent of people who become infected with West Nile virus will not show any symptoms, although some 20 percent will develop West Nile fever.

Of those, less than 1 percent may develop a more severe form of illness with symptoms such as high fever, headache, neck stiffness, disorientation, coma, paralysis and in extreme cases death. While there is no cure for West Nile virus, it is preventable.

Residents can help reduce the threat by eliminating unnecessary standing water in discarded tires, buckets, kiddie pools and stock backyard ponds or other permanent water features with mosquitofish. Residents are encouraged to report mosquito problems, neglected swimming pools or dead birds to the West Nile virus hotline at 1-877-968-2473 or online at www.westnile.ca.gov.

— Patch Staff contributed to this report.