Last year's flu season was the worst California had seen in years - and state health officials warn this year could potentially be just as bad. While forecasting disease isn't an exact science, there are some troubling signs. In Asia, the flu has made an early comeback, and quickly swelled to epidemic proportions in Japan and Taiwan. And stateside, some experts are sounding the alarm about continued lower uptake of the flu vaccine. There's also the possibility of a seasonal COVID-19 wave - the likes of which didn't materialize last winter, but had been commonplace since the pandemic - as well as a simultaneous rise in respiratory syncytial virus, or RSV.