Nikki2019 wrote:... I wonder if vaccinations for pneumonia would be wise for a precaution for 4s. ...
Which infections are thought to be linked to Alzheimer's disease?
Some of the infections that are thought to be linked to Alzheimer's include oral herpes, pneumonia and infection with spirochete bacteria (the type which cause Lyme disease and some types of gum disease).
Chlamydophila pneumoniae is the bacteria that causes pneumonia and bronchitis. It usually infects the respiratory tract. However, it can also evade the immune system and remain as a chronic infection inside cells, including white blood cells. This is especially common in people over 60. The bacteria has been found inside the brain cells of people with Alzheimer's disease. Its presence in the brain could cause inflammation , which could contribute to the underlying Alzheimer's disease mechanism
The article cites this [paywalled] 2015 paper: Bacterial infection and Alzheimer's disease: a meta-analysis.
which provides this finding in the abstract "We found over a five-fold increased occurrence of AD with Cpn [Chlamydophila pneumoniae] infection (OR: 5.66; 95% CI: 1.83-17.51)."
Which suggests that bacterial pneumonia, particularly later in life, is a definite risk factor for AD. As to whether you should get vaccinated, I guess you'll need to look at relative risk scores to decide what makes sense for you. (Personally, I'm a big fan of vaccinations for life (or at least, disability) threatening diseases which I have a reasonable chance of succumbing to. Of course, others have strongly disagreeing views.)