WASHINGTON — It's time for flu shots again, and health officials expect to avoid a repeat of the misery last winter, when immunizations weren't a good match for a nasty surprise strain. More than 170 million doses of flu vaccine are expected this year, with options ranging from traditional shots, a nasal spray, a high-dose version for seniors and even a needle-free injection for the squeamish. "Getting the flu vaccine is the best way to protect yourself against the flu," Dr. Tom Frieden, director of the Centers for Disease Control and Prevention, said in an interview Thursday.