Mosquito control officials say they are considering aerial spraying over urban areas to combat mosquitoes as more insects test positive for West Nile virus in Sacramento and Yolo counties.
The Sacramento-Yolo Mosquito and Vector Control District reported that laboratory results received Wednesday confirm 26 mosquito samples tested positive for West Nile virus. Officials say they are closely monitoring Elk Grove, Woodland and Davis and that aerial spraying over the urban areas may be needed to reduce the number of infected mosquitoes.
Last week, a Nevada County resident became the first in California this year to die from West Nile virus, according to the state Department of Public Health. The state has entered the peak season for West Nile outbreaks, and residents are urged to protect themselves from mosquito bites by using mosquito repellent outdoors.
Mosquito control officials said that as a result of increased West Nile virus activity, ground fogging will intensify around parks and other areas of Sacramento County where affected mosquitoes are found.
Yolo County residents, in addition to intense ground treatments, will see aerial spraying of agricultural areas outside Davis and Woodland focused on creating a buffer to reduce the West Nile danger to the urban areas. Additional surveillance results will be available early next week to help determine whether urban aerial spraying will be necessary, officials said.
The first sign of West Nile virus activity this season came in early June when a mosquito sample from an agricultural area between Davis and Woodland tested positive. Since then, officials say, the activity has steadily increased and, in recent weeks, intensified. The same pattern developed around Elk Grove, with many mosquitoes and birds testing positive throughout the city.
In Sacramento County, 37 mosquito samples and 21 dead birds have tested positive for West Nile virus to date this year. In Yolo County, 56 mosquito samples and 16 dead birds have tested positive.