In the summer of 2019, Gregg McChesney was in great shape. At the time, the 64-year-old had even been assisting his younger brother, Mark, with some heavy labor around his farm. But when Gregg was bitten by an insect, his health began to deteriorate at an alarmingly fast pace. Within just days of the incident, in fact, the grandfather was pronounced brain dead. And, at first, no one – not even the doctors – could explain why this tragedy had taken place.