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County Health Officials Report Death of SLO County Resident from West Nile Virus

Author: Public Health Department
Date: 7/9/2021 4:00 PM

Officials remind residents to avoid mosquito bites and drain standing water

A resident of San Luis Obispo County has died from complications of West Nile virus. This is the first reported case of and death from West Nile virus in California in 2021. Case investigations suggest the individual became infected with West Nile virus during travel to an endemic area of California and that the virus was not acquired in SLO County.

“We extend our sincere condolences to this patient’s family,” said Dr. Penny Borenstein, County Health Officer. “This loss is a tragic reminder that West Nile Virus is here in California and can cause very serious illness. Please, be sure to protect yourself from mosquito bites and drain any sources of standing water where mosquitoes can breed.”

West Nile virus is commonly transmitted to humans and animals by mosquitoes. While most people infected with West Nile do not experience any symptoms, about one in five experience flu-like symptoms and a small number of people (less than one percent) develop serious neurologic illness. The risk of serious illness is higher for people over 50 years of age and people with certain medical conditions such as diabetes and hypertension. West Nile virus activity typically follows a seasonal pattern based on mosquito populations.

To prevent mosquito bites, focus on protecting yourself and your home:

  • Apply a repellent that contains DEET, picaridin, or oil of lemon eucalyptus.
  • Wear protective clothing such as long-sleeved shirts and pants.
  • Be alert at dawn and dusk. Mosquitoes that transmit West Nile virus usually bite in the early morning and evening.
  • Check and repair all screens, including screen doors, to keep mosquitoes out.

To eliminate mosquito breeding sites around your home, focus on eliminating standing water:

  • Find and drain containers that collect water around the yard, such as flower pots.
  • Clear roof gutters so water can drain properly.
  • Clean bird baths, fountains, pet dishes, and other water sources at least once a week.

More information on West Nile virus activity in California is available at Mosquito prevention tips and resources for San Luis Obispo County—including special recommendations for golf courses, wineries, and other agricultural properties—are available at