evidence: PolitiFact has seen repeated and unsubstantiated claims that covid vaccines have caused mass numbers of deaths. A recent widely shared post claimed 17 million people had died because of the vaccine, despite contrary evidence from multiple studies and institutions such as the World Health Organization and CDC that the vaccines are safe and help to prevent severe illness and death. [...] Covid vaccines also have been blamed for causing Alzheimer’s and cancer. Experts have found no evidence the vaccines cause either conditions.