Had #2 10 days ago along with my staff(10)who are all in mid forties. With the exception of one, they all had 3 day flu-like symptoms. My only reaction was the following day. Was in Florida following day. 74 degrees, grilling some burgers with my brother and wearing three layers and hooded sweatshirt. 3 hour fever spike and chills then done. No problem at all - except for taking days and days of crap from my brother.