Neisseria meningitidis is a gram-negative diplococcus which causes invasive disease. The most frequent clinical manifestations caused by infection with this pathogen, are meningitis and fulminant septic shock. More benign forms with a sub-acute or chronic pattern are rare but still can evolve to meningitis and have a fatal outcome. This entity is difficult to recognize, as febrile erythema with otherwise good general condition may simulate other diseases, namely viral infections. The authors reported the cases of two healthy young adults who were misdiagnosed with a viral infection. What they really had was a meningococcemia without meningitis presenting with mild and unspecific symptoms, such as, intermittent fever and a discrete macular rash. We pretend to highlight this rare, unspecific and heterogeneous symptoms which can provoke negligence of a potentially life threatening condition.