Public Service Announcement 8/14/2023

Yuba County Public Health has confirmed the first human case of West Nile Virus (WNV) in Yuba County this year. As of August 11, 2023, fourteen human WNV cases have been reported in California. WNV is active June through October. Both of the recently confirmed local human WNV cases are experiencing severe illness.

People infected with WNV generally fall into three categories:

• No symptoms/asymptomatic (8 in 10 people)
• Mild to moderate fever illness with fatigue and body aches (1 in 5 people)
• Severe illness with neurologic symptoms such as encephalitis or meningitis (less than 1 in 150 people).

For those who develop a severe WNV illness, symptoms may last several weeks and some symptoms may be permanent.

Although abundance for the mosquito species capable of transmitting West Nile virus is trending downward, the risk of West Nile virus continues to be high throughout Sutter and Yuba counties. “We continue to see increased virus activity and detections in our surveillance system. The risk for human infection is high,” said Stephen Abshier, District Manager. “Residents need to remain vigilant in protecting themselves from being bitten by mosquitoes” added Abshier. Residents should inspect their yards for anything holding water. Regular landscape irrigation or unseasonable rains, as forecast for this coming weekend, can provide mosquitoes with good breeding habitat. Simply draining or dumping water will prevent new mosquito breeding.

“The best way to prevent West Nile virus infection is to avoid mosquito bites. We want to remind everyone to stay protected by wearing long pants and long sleeves, especially at dawn and dusk when mosquito activity is high, and by wearing a good mosquito repellent,” said Bi-County Public Health Officer, Dr. Phuong Luu.

WNV is transmitted to humans and animals by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Residents can reduce the risk of infection by practicing the “Three Ds”:

1. DEET – Use a proven insect repellent like DEET. Other recommended repellents include: picaradin, lemon eucalyptus oil, para-menthane-diol, IR3535 or 2-undecanone. Always use according to label instructions. DEET can be used safely on infants and children 2 months of age and older.

2. DAWN AND DUSK – Mosquitoes that transmit WNV bite in the early morning and evening. Wear proper clothing and repellent if outside during these times. Make sure that doors and windows have tight-fitting screens to keep mosquitoes out. Repair or replace screens with tears or holes.

3. DRAIN – Mosquitoes lay their eggs on standing water. Eliminate or drain all sources of standing water on your property, including flower pots, old car tires, rain gutters and pet bowls. For standing water that cannot be drained such as fountains, ponds, etc., consider adding “Mosquito Dunks” or mosquito fish, which feed on mosquito larvae.

In response to recent findings and increased virus activity, District staff will continue to trap mosquitoes for testing, continue our disease surveillance program, and treat areas of high WNV activity to reduce the adult mosquito population. Spray areas can be viewed at the District’s website at www.sutter-yubamvcd.org. A surveillance map can be found there as well, which shows the location of WNV positive dead birds, mosquito collections and sentinel chickens.

2023 West Nile Virus activity update:

Yuba County:  1 human, 0 dead bird, 17 mosquito collections and 3 sentinel chickens have tested positive for WNV as of August 11, 2023.