County confirms first human West Nile Virus death of 2021

Madera County is reporting a fatality from West Nile Virus (WNV). The fatal case, an adult male, was one of the first two cases identified in August. Both cases required hospitalization and the second, non-fatal case has improved and been discharged from the hospital. Following investigation, these two were considered unrelated.


WNV is transmitted to people through the bite of an infected mosquito. The mosquito abatement control agency was notified at the time of the original diagnosis and spraying was planned in the areas where the positive tests were localized.


Most people infected with WNV have no symptoms. About 25 percent of people with WNV may have fever, headache, and other nonspecific symptoms. Fewer than 1 percent of infections develop severe disease or neuroinvasive disease, with symptoms of fever, headache, stiff neck, confusion and decreased alertness. People over 50 years of age or with weakened immune systems are at greater risk of experiencing severe symptoms when infected. There is no vaccine.


“We are saddened by this loss, and it is a reminder of the risks from WNV-infected mosquito bites. You can decrease your risk for WNV and other viruses transmitted by mosquitoes by using EPA-registered repellent to keep mosquitoes from biting you, mosquito proofing your home through the use of properly fitting doors and screens, and not allowing standing water to collect in your home or yard,” stated Simon Paul, M.D., Madera County Public Health Officer:


For more prevention tips and information about WNV, visit the following websites: California Department of Public Health: https://westnile.ca.gov/, Centers for Disease Control and Prevention: https://www.cdc.gov/westnile/index.html and Madera County Mosquito & Vector Control District: http://maderamosq.org/.