Rep. James Comer (R-KY), chair of the House Oversight Committee, told Fox News that he had not been in contact with any White House whistleblowers about President Joe Biden’s health. Earlier this week, Comer’s committee subpoenaed three of Biden’s White House aides in connection to what Republicans alleged was a coverup of the president’s mental fitness. “We believe this has been going on for a long time,” Comer told Fox News host Martha MacCallum on Thursday. “We want to know what these three specific staffers knew, and we want to know who, in fact, has been pulling the strings behind the cur…