A GhD is short for Doctor of Google. It is used to refer to people who consider themselves experts on a subject because of their extensive googling of answers even though their knowledge is based on confirmation bias and the reading of severely slanted or conspiracy based websites.
That Karen and her GhD is delusional in their defense of how vaccines are all part of a conspiracy by "Big Pharma" and "Bill Gates" to try and control the world and depopulate it.