A 61-year-old Alpine man is the first person in San Diego County to test positive for West Nile virus this year, local health officials reported Wednesday.
The man, whose name was withheld, was hospitalized and has recovered. The California Department of Public Health confirmed his WNV diagnosis on Tuesday.
The man said he had traveled to Yuma, Arizona where it is believed he contracted the virus, according to the San Diego County Health and Human Services Agency.
Since Jan. 1, there have been two West Nile virus-positive detections in mosquitoes during routine trapping by the county vector control program, one in the Del Mar Area and the other in the Black Mountain Ranch area.
There were only three human cases of West Nile virus in San Diego County in 2019 and two in 2018.
The state has reported 11 people infected statewide so far in 2020, including a child in neighboring Orange County who was diagnosed sometime last week and was hospitalized but is expected to recover.
West Nile virus is mainly a bird disease but can be transmitted to people by certain species of mosquitoes that first feed on an infected bird or animal and then a bite a person.
Around 80% of people who become infected with West Nile virus never know it and never suffer any symptoms. About one in five people who are infected develop a fever and other symptoms such as headache, nausea, fatigue, skin rash or swollen glands. About 1 out of 150 infected people could become extremely ill and die.
People older than 50 and who have underlying medical conditions are at heightened risk.
Public health and environmental health officials recommend following the county's "prevent, protect, report" guidelines, which are designed to help residents protect themselves from mosquitoes that transmit West Nile virus as well as invasive Aedes mosquitoes that can transmit tropical diseases, including Zika, dengue and chikungunya.
Dump out or remove any item inside or outside homes that can hold water, such as plant saucers, rain gutters, buckets, garbage cans, toys, old tires and wheelbarrows. Mosquito fish, available for free by contacting the county's vector control program, may be used to control mosquito breeding in backyard water sources such as unused swimming pools, ponds, fountains and horse troughs.
Wear long sleeves and pants or use repellent when outdoors. Use insect repellent that contains DEET, picaridin, oil of lemon eucalyptus or IR3535. Make sure screens on windows and doors are in good condition and secured to keep insects out.
Finally, report increased mosquito activity or neglected, green swimming pools and other mosquito-breeding sources — as well as dead birds — to the vector control program by calling 858-694-2888 or emailing vector@sdcounty.ca.gov.
Mosquito season in Southern California generally spans May to October.
