A resident in San Bernardino County has died of West Nile virus, according to a release from the County’s Department of Public Health.

The unidentified resident suffered from pre-existing conditions, officials said, and is among seven residents in the County to test positive for the potentially deadly disease this year.

In 2022, four people tested positive for West Nile virus, with one death reported.

San Bernardino County Health Officer Michael A. Sequeira said increased rainfall this year has led to a surge of mosquito activity and rainfall from the recent Tropical Storm Hilary is likely to make that problem even worse.

“We urge everyone to take proactive measures to eliminate potential breeding sites around their homes and to protect themselves from mosquito bites,” Sequeira said.

West Nile can cause a number of serious symptoms, including fever, body aches, rash, nausea, vomiting and headaches.

Most people who become infected experience no symptoms at all, but people 50 and older, as well as those with underlying conditions like diabetes, hypertension and compromised immune systems, have a higher chance of getting sick and developing severe complications.

More serious symptoms include high fever, severe headache and stiff neck, and require immediate medical attention.

Health officials say the easiest and most effective way to avoid infection is to prevent mosquito bites, which happen more regularly in summer and fall, particularly around dawn and dusk.

Residents can mitigate their risk of West Nile exposure by taking precautionary steps to reduce mosquito contact, including emptying standing water on property, wearing appropriate clothing that covers the body, using insect repellant and contacting proper authorities to report neglected pools and standing water. In San Bernardino County, residents can call the County’s Mosquito and Vector Control Program at 800-442-2283.

Last week, Riverside County confirmed its first two cases of West Nile virus. So far, no deaths have been reported in the neighboring county.