>>Wrong. It is possible to get systemic reactions to a flu shot.<<
Would you please expound on that? I was told the same thing.
Most of the literature on systemic reactions, adverse effects, and drug interactions require a journal subscription to access it via computer. Some of the information can be found in the literature accompanying the vaccine. The literature basically says that fever, malaise, myalgia and other reactions can occur, usually within 6 to 12 hours and persist for a couple of days. There are some people who should avoid the vaccine, e.g., those taking certain drugs and those who are immunosuppressed.
The topic has been well studied by epidemiologists and other researchers. If you go to the library you might be able to access some government publications, e.g., Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR 2004;53: 1-40.
I’m not sure why some health care providers make such blanket statements. Maybe they figure the benefits far outweigh the costs - and they probably do for most people.