> How can you compare the potential of a version of you who never had vaccines with a version of you who had a given set of vaccines These are called identical

> How can you compare the potential of a version of you who never had vaccines with a version of you who had a given set of vaccines These are called identical twin studies, they're inherently limited in capacity and are not an appropriate means of studying vaccines. Vaccines are inherently something widely distributed to the public. Vaccines do have adverse effects on some people, all publicly released vaccines have publicly available figures on the likelihood of adverse effects in a percentage of the population. If the percentage is too high or the types of effects are too severe then the vaccine is not released to the public - this is common sense. For example I was seemingly affected by a Whooping Cough (Pertussis) vaccine I was administered as a baby. After receiving part of the vaccine (it was administered in doses at the time) I became quite ill and doctors advised against administering the rest of the vaccine. So for many years I was not vaccinated against Whooping Cough but received the rest of my vaccinations without issue - again, should be common sense. I'm a perfectly healthy adult now and have actually since received a newer/different a Whooping Cough vaccine (I don't believe they still administer the old one), as well as several other vaccinations. I'm perfectly content with the fact a vaccine may have almost killed me, it's certainly better than the alternative of Whooping Cough running rampant killing more than the 50,000 people it already kills each year.