Placer Mosquito & Vector Control warns Lincoln residents: West Nile surveillance rising; invasive Aedes found in neighborhoods

Placer Mosquito and Vector Control District presented its annual update to the Lincoln City Council on June 10, reporting that as of the district’s last update there were no West Nile virus detections in Placer County but state surveillance showed an increasing number of positive dead birds and mosquito samples.

The district’s public information officer, Megan Lovano, said the statewide picture is beginning to show virus circulation — "as of today ... we have not found it in any dead birds, any mosquito samples. There's no human cases. But in the state, there's been 13 positive dead birds and 74 positive mosquito samples." She told council that dead-bird reports are an early indicator: a handful of positive dead birds is often followed by positive mosquito samples a week or two later.

Nut graf: The district urged residents to report dead birds at westnile.ca.gov, remove standing water where mosquitoes breed, use EPA‑registered repellents (ingredients such as DEET, picaridin, IR3535 or oil of lemon eucalyptus), and ensure door and window screens are intact. The district also discussed the growing problem of invasive Aedes aegypti, an aggressive daytime biter that can spread dengue, Zika, chikungunya and yellow fever if the virus is present.

Key details presented - Surveillance and timing: Countywide mosquito testing runs from spring into October or November; climate change is lengthening the season. As of the district’s May update, no West Nile positives were detected in Placer County, but state counts had begun to rise. - Dead birds: Dead-bird reports are a key surveillance tool. Lovano said, "We ask ... to try to get as many dead bird reports as possible because we test those dead birds for West Nile virus." A council member reported a dead finch outside city offices and said he had submitted a report online during the presentation. - Invasive Aedes aegypti: The district said it has found invasive Aedes in Downtown Lincoln and the north part of Lincoln as well as Roseville and Rocklin. Last year the district reported 51,692 mosquitoes trapped during a nine‑month surveillance effort, and 51,692 of those were cited as total mosquito captures with 51,692 and 51,692 of which 51,692 were female — staff reports included the figure 51,692 total mosquitoes with 49,000+ female captures and 51,692 Aedes aegypti specifically. Staff said they found invasive Aedes in 19 neighborhoods last year, 15 of which were newly detected. - Protection measures: The district emphasized source reduction (dump and drain standing water, scrub eggs from containers), using EPA‑registered repellents and vaccinating horses (a vaccine exists for horses). Lovano also described the district’s mosquito‑fish program and the use of drones to apply larvicide in low‑lying areas.

Questions and next steps Council members and staff asked about local detection timing. Lovano said Placer County usually sees its first local positives in June or July, often beginning near Roseville. The district recommended residents sign up for email notifications for treatment alerts and monthly updates and to use the district website for service requests (for example, mosquito fish delivery).

Ending Lovano asked residents to report dead birds immediately and to remove standing water. She closed by offering the district’s outreach and service request channels for Lincoln residents and invited council questions.