An infectious disease arrives in San Francisco and is immediately associated with residents of Chinatown. Scientists and public health officials try to stop the spread. White residents believe they are immune. Politicians and the business class say the disease is not real because they worry about hurting commerce. Vulnerable people die in droves. A new PBS documentary, “Plague at the Golden Gate,” takes viewers back to 1900 when the bubonic plague hit San Francisco in a manner eerily similar to the way the COVID-19 pandemic has played out the past three years. The film examines how racism, discrimination, and misinformation contributed to the spread of the disease. We’ll talk about the film and how history is repeating itself.