A San Francisco man is recovering after reporting the first human case of West Nile virus contracted locally in seven years, health officials said.
The unidentified man, who was recovering at home, had not traveled outside the Bay Area recently, according to a statement from the San Francisco Department of Public Health. The department said there is no way to know if the man was infected within San Francisco or a surrounding county.
The report of the human case follows a case of an infected bird found dead recently near City College of San Francisco. The infected bird was only the third one found in The City since 2007.
For humans, the last San Francisco case of West Nile virus was in 2010 when a resident contracted the disease through an organ transplant, the health department said.
The start of the warm-weather season in The City, when mosquitoes breed in stagnant water, had led the health department to issue a warning after the infected bird was found.
“San Franciscans will be at risk for West Nile during the summer and fall when mosquito activity is at its peak,” said Dr. Rajiv Bhatia, the health department’s medical director for environmental health.
In California, 165 cases of West Nile, including eight deaths, had been reported as of Tuesday, according to the health department. The Centers for Disease Control and Prevention said 3,142 cases and 134 deaths had been reported in 48 states as of Sept. 18, making it the highest reported year-to-date since 2003.
The majority of West Nile cases are not fatal, according to health officials, and four out of five people who contract the virus do not experience any symptoms.