The virus has spread across most of the United States since it was detected in New York in 1999. About 500 people have been infected so far this year, the federal Centers for Disease Control and Prevention reported.
The California Department of Health Services reported 116 infections in the state as of Wednesday, with most cases in San Bernardino and Los Angeles counties. The latest victim, Richard Shaddox, 81, who died Tuesday, lived in San Bernardino County.
"That man was strong enough, he would have lived to be 100," his widow, Yvonne, said Wednesday. "He didn't use a cane, or a walker, nothing. Until the Nile got him, then he went from a cane, to a crutch to a wheelchair."
One of the primary breeding sources of mosquitos is stagnant, standing water, and on Wednesday the Los Angeles City Council gave preliminary approval to rules that would streamline fines of up to $1,000 a day on residents or businesses that fail to remove such water from their property.
The county's largest vector control district can already levy such fines but the process takes several weeks. The council ordered the city attorney to draw up language for the law, which should be ready within weeks.
San Bernardino County has had an active West Nile campaign that has included removal of standing water and the spraying of pesticides.
The other victims in California were a 57-year-old man who died in Orange County in June, a 75-year-old man who died in San Bernardino County in July, a 91-year-old Los Angeles woman who died last week, and an 88-year-old Long Beach woman who died Monday.