MSNBC staffers were left scrambling this week when the network’s Manhattan headquarters was infested with bed bugs, RadarOnline.com has learned. The icky incident reportedly took place on Sunday – just hours before MSNBC was scheduled to start its coverage of this year’s Super Tuesday. According to a memo issued by the network, at least one “unidentified insect” was spotted on Sunday in studio 3A of the network’s 30 Rock headquarters. Studio 3A is home to both The Rachel Maddow Showas well as MSNBC’s special election coverage, and the studio was temporarily shuttered “out of an abundance of ca…