Following a report out of Marin County last week about a 48-year-old man who died from meningitis, there's another case report here in San Francisco. ABC 7 reports that 53-year-old Laura Robson was found dead, sitting upright in the back of a Muni bus in Daly City — possibly a 14 bus, at the end of the line — and preliminary test results suggest she died of meningitis. It's unclear how long she had been on the bus, but she passed away last Tuesday.

Robson's brother, David Robson, told the station that the San Mateo County Coroners Office informed him on Wednesday that preliminary autopsy results point to meningitis, and he and and his son were told to seek prophylactic antiobiotics. They had spent the previous weekend with Robson in Santa Rosa. Her brother says she was suffering from a severe headache and a fever at the time.

Ten days before she fell ill, Robson had had surgery on her shoulder at SF General.

This is the second local fatal case of meningitis in the last week, believed to be bacterial, and the identity of the first victim has now been revealed as Sevin Phillips of San Rafael. Phillips was known to work out at the SoulCycle in Larkspur, and as a result some 300 people who attended the cycling gym between New Year's Eve and January 7 have received notice that they could have been exposed to the disease. As CBS 5 reports, no other cases have been reported in Marin.

Update: A preliminary autopsy lab test has come back negative for meningitis, and Robson's cause of death is now unclear.

Related: Marin County Meningitis Death Puts Larkspur SoulCycle Riders On Alert