Investigators still racking their brains to figure out what's caused dozens of mystery illnesses globally
                                
                                
                                    (Newser) -
                                    In 2019, a White House official  walking her dog in Arlington, Va.,  suddenly experienced ringing in her ears, felt her face start to tingle, and came down with a headache. In early November 2020, a National Security Council official  fell ill after walking near the Ellipse , on the White House'...