** Shares of diagnostics company QuidelOrtho QDEL.O fall 3.31% to $11.96 in premarket trading

** Co appoints Micah Young as CFO, effective July 6

** Young most recently served as executive vice president and CFO of medtech firm Masimo Corporation

** Young succeeds Joseph M. Busky, who will serve in an advisory role to support transition

** YTD, the stock has fallen ~57%