First confirmed samples of West Nile virus found in Petaluma mosquitoes. Here’s how to minimize your risk

Officials with the region’s lead mosquito control agency are urging residents protect themselves against West Nile virus after routine testing uncovered the first confirmed presence of the virus in mosquitoes near popular Petaluma walking trails.

Scientists with the Marin/Sonoma Mosquito Vector Control District confirmed the virus in mosquitoes collected near the city’s Ellis Creek Water Recycling Facility, marking the first such detection in either North Bay county this year, district spokesperson Nizza Sequeira said Thursday.

“We do generally see virus activity in that particular area, and the last time we detected West Nile virus there was in 2018,” Sequeira said.

The 270-acre treatment plant sits off Lakeville Highway next to Shollenberger Park, with busy walking trails meandering through various wetlands and across Adobe Creek. The Petaluma Wetlands Alliance estimates several hundred people visit the Shollenberger trails each day.

The West Nile virus is the leading cause of mosquito-borne disease in the continental United States, according to the Centers for Disease Control. Among those infected, about one in five experience symptoms, while one in 150 develop serious or sometimes fatal illness from the virus.

Residents are urged to dress appropriately to minimize possible mosquito bites, to minimize standing water in their yards and to contact the district for any issues with the insect.

Contrary to some misconceptions, Sequeira said the virus remains a threat despite the region’s severe drought.

“While there may be a lesser amount of water in creeks and in other areas, you do find more pond-ed areas of water and those happen to have a higher concentration of mosquito larvae,” she said. “And we also have residents collecting and reusing water, so they have barrels and buckets of water that aren’t necessarily covered like they should be.”

Earlier this month, the district found the first dead bird infected with West Nile virus this year, from a crow collected in Santa Rosa.

But with the Petaluma location the only confirmed sample at the time, Sequeira said her top advice is for those who frequent the facility and its nearby trails.

“First and foremost, if people are going to be out, especially during dusk and dawn, is to take personal preventative measures like wearing repellant, long sleeves and pants,” Sequeira said. “Especially if people are walking in the area of the Ellis Creek (facility).”

The District serves 763,000 residents in a nearly 2,300 square mile area across the two counties, and responds to more than 4,500 requests each year. Funded through property tax, its services to help residents minimize mosquito risks are free of charge, Sequeira said.

Officials with the district say they will continue to trap, test, and monitor the distribution and abundance of adult mosquitoes in the vicinity of the Ellis Creek Water Recycling Facility throughout the season.

Contact Kathryn Palmer at kathryn.palmer@arguscourier.com, on Twitter @KathrynPlmr.