I'm really sorry for the late response. I entered some keywords (link 1) into PubMed database and it seems that not much is known about polio and AD. The only relevant study (link 2), published in 2001, shows that polio vaccination may decrease the risk of AD.
But it's unclear if this result is due to the ability of poliovirus to contribute to AD or due to the non-specific effects of vaccines. Yes, vaccines sometimes have unintended effects on the immune system, such as protection against other diseases, which I also wrote about (link 3).
Not sure if that helps, but thank you for sharing your experience. I hope you and your family can cope well with the AD happening.
1. https://pubmed.ncbi.nlm.nih.gov/?term=polio*%5Btiab%5D+AND+alzheimer%27s%5Btiab%5D&size=200
