Prof Stabell-Benn has some good YouTube videos (like this one) about live versus dead vaccines.
She says that the World Health Organisation (WHO) have been aware of the non-specific off-target effects of vaccines for 20 years, but have shown little interest in pursuing this research. Neither have the pharmaceutical companies shown much interest in investigating non-specific effects.
Her research is so fascinating. She got so much resistance prior to COVID-19 for just mentioning this stuff - showing that people who received live vaccines had better survival rates when you had NONE of the circulating pathogen (meaning people who got an OPV had better childhood survival rates in areas with zero polio - just seemed to improve their immune systems).
Sadly, once COVID started, she went from being ignored to being a pariah. Now her amazing work will get no serious attention, even though it all predated COVID. She's been branded anti-vaxx, despite studying vaccines in Africa for many years. Shows our level of propaganda - someone who says, "Hey, of these two vaccines, option B might be better after all." You anti-vaxxer!!!
In addition to what @Hip mentions about the rise of ME/CFS, I've never been clear that PPS (Post Polio Syndrome) is actually a separate illness. It's very similar to Long Covid. In the aftermath of polio, while 0.5% of people were paralyzed, 15%-40% had long term symptoms that usually only manifested many years after the initial infection. Millions were affected. It was a big area of research in the 70's and 80's, then as their patients died off, people stopped funding and stopped caring. Even ID doctors today are wildly unfamiliar with it.