First human case of West Nile virus illness found in Stanislaus County

A 52-year-old Stanislaus County woman has been hospitalized with the West Nile virus, the first human case in the county this year, the Health Services Agency reported Friday afternoon.

The patient has not been interviewed, so it’s not known whether she had any underlying health issues, said Dr. John Walker, county public health officer.

“But beginning last year,” he said, “the state public health officer especially noted the risk of patients with diabetes for the encephalitis form of the disease, which is the most serious and which, unfortunately, this woman has. It’s a neuroinvasive disease, so people with diabetes and other diseases that affect the immune system need to be especially careful.”

The risk from West Nile virus infection also increases with age, Walker said, though last year, a couple of college students in Stanislaus and San Joaquin counties fell ill.

“In cases where we have had nurses investigate in the past, most of the affected persons don’t recall a mosquito bite,” Walker noted. “These are really small mosquitoes. ... We caution people to protect themselves, especially at high-risk times of day, which are dawn and dusk, and if you have to be out, use repellent such as DEET.”

As of Friday, there have been 18 known human cases of West Nile virus in California this year.

Health Services urges these steps to help protect against mosquito bites and West Nile:

▪ Eliminate sources of standing water where mosquitoes lay eggs.

▪ Avoid spending time outside when mosquitoes are most active – especially the first two hours after sunset.

▪ When outdoors, wear long pants, long-sleeved shirts and other protective clothing.

▪ Exclude mosquitoes from your home with tight-fitting screens on windows and doors.

▪ Apply insect repellent containing DEET when outdoors.

▪ In addition to DEET-based products, the Centers for Disease Control and Prevention also recommends repellents containing oil of lemon eucalyptus and Picariden.

The East Side and Turlock mosquito abatement districts are busy locating and treating mosquito breeding grounds. One source can be neglected swimming pools, so the districts have conducted aerial surveillance to look for them.

It’s good to change the water in pet dishes and birdbaths regularly. Other potential havens for mosquitoes are rain gutters, flowerpots and old tires.

County residents may report mosquito problems to the abatement districts. Residents of Modesto and other communities north of the Tuolumne River may call the East Side Mosquito Abatement District at 209-522-4098. For everyone else, the Turlock Mosquito Abatement District can be reached at 209-634-1234.

Reporting and testing of dead birds is an important step in preventing West Nile. A confirmed case of the virus in dead birds or mosquitoes helps identify areas that need treatment. Report dead birds by calling the state hotline at 877-968-2473. Of particular interest are crows, ravens, magpies, jays and raptors (hawks and eagles).

“One other thing,” Walker said. “The schools are starting to open and ... for some folks, there’s the sense that we’ve passed (the risk season), summer’s almost over. But in this county, our risk period lasts at least until the end of September and, because of the drought, may be even longer.”

Go to www.stanemergency.com for more West Nile virus information.

This story was originally published August 7, 2015 at 3:24 PM with the headline "First human case of West Nile virus illness found in Stanislaus County."