To justify its policy of recommending everyone get an annual flu shot, the CDC asserts that influenza vaccination, despite its abysmal effectiveness, still prevents "thousands of hospitalizations and deaths".

Turning to the CDC's source for this claim, a study carried out by CDC researchers, one finds that their claim is not a demonstrated effect of vaccination, merely an assumption based in on "hypothetical vaccine effectiveness estimates".

Meanwhile, the meta-analysis of studies in the medical literature on influenza vaccine effectiveness by the prestigious independent Cochrane Collaboration, published in the Cochrane Database of Systematic Reviews, finds that vaccination "had no effect on hospital admissions or complication rates."

Par for the course for the CDC.