SAN DIEGO (CNS) - A 19-year-old Escondido man contracted West Nile virus, the first local case of the potentially deadly, mosquito-borne disease in three years, the San Diego County Health and Human Services Agency announced Thursday.
The patient's condition was discovered when he donated blood, which was screened and WNV was detected. However, he has not shown any symptoms, which is one of the possible outcomes of infection, according to the HHSA.
According to the agency, the last human case in San Diego County was reported in 2009.
"Even though (county) Vector Control has been actively monitoring and no mosquitoes have tested positive for West Nile this year, this is an indication that the virus is here," said Dr. Wilma Wooten, the county's public health officer. "It's important for the public to know West Nile virus is a dangerous and potentially deadly disease."
Last month, authorities reported 113 human cases around the United States, seven in California. One of the California victims died last week, according to the HHSA.
About one in 150 people infected with West Nile virus will develop serious symptoms that could prove fatal, according to the agency. The risk is greater for people over 50 years old or who might have weakened immune systems.
Four out of five people who are infected will not have any symptoms.
The young Escondido man did not recall having been bit by a mosquito. County personnel inspected his home and set traps, according to the HHSA.
The agency recommends that people remain vigilant for standing water, including swimming pools in vacant homes, remain indoors when mosquitoes are active around dawn and dusk, and wear long sleeves and long pants if outside at those times.