In both studies, individuals who had received at least one vaccination—a flu shot in one study, and a pneumonia vaccine with or without a flu shot in the second—were less likely to be diagnosed with Alzheimer’s later in life. While the studies are slightly different, their similar conclusions suggest that vaccines may play a broader role in strengthening a person’s lifelong resistance to some diseases.
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Both teams are working to determine the biological mechanisms that explain their findings, but they do have some preliminary thoughts. [Geneticist Svetlana] Ukraintseva, speaking to MedPage Today, proposes that because so many different types of pathogens have been implicated in Alzheimer’s, including viruses, bacteria, and fungi, vaccines could provide benefits simply by keeping people protected from the more general wear and tear of life.