A family member told KTVU that Griffith, who died on 10 August in Lake Chapala, had developed the disease following a tick bite in Oregon in 2015.
The Texas-born journalist began her career working as a reporter for the Associated Press and Denver Post. She moved into television when she joined KTVU in the Bay Area in 1986 as a weekend reporter and anchor.
The Emmy Award winner went on to become the co-anchor of the station’s 10pm news broadcast alongside Dennis Richmond, before resigning in 2006.
Fellow journalists paid tribute to Griffith on social media after her death was announced.
“Leslie Griffith was a consummate professional,” KTVU reporter Greg Liggins.
“During my first stint at @KTVU in the 90s, my first chance to sit on the anchor desk was to fill in for Leslie, who then solo-anchored weekends. They were big shoes to fill!
“She was professional, engaging, and adored by her audience. Leslie performed journalism the right way, focused on the story. She will forever remain part of a lengthy list of talent that made KTVU a destination station for news. RIP, Leslie.”
CNN correspondent Sara Snider took to Twitter and wrote, “This hurts my heart. She had such a wild & wonderful personality. She stood up for good reporting on so many occasions. She stood up for me on occasion too. She was a force of nature.”