While the cdc advises a yearly flu shot, some people object. FWIW, I get mine yearly.

From a website called stat:


When researchers followed 328 households during the 2010-11 flu season,they found — much to their surprise — that the only people who seemed to benefit from immunization were the ones who hadn't gotten a flu shot the year before. These "unexpected findings ... require further study," the researchers wrote in 2013.

A larger and more robust study,published last year in Clinical Infectious Diseases, added more evidence that the 2013 study was onto something important. Researchers followed more than 7,000 people for eight yearly flu seasons, and they learned that people got the strongest protection against the flu only when they were vaccinated for the current season — and at no other time during the previous five years