Abstract: Neisseria meningitidis PorA constructs are provided which have one or more disrupted variable regions created by insertion of entire conserved regions or conserved region amino acids. The highly immunogenic variable regions of PorA are responsible for eliciting strain-specific immune responses that are not broadly protective, so disruption of the variable regions directs the immune response against conserved region epitopes to effectively immunize against a broader spectrum of N. meningitidis strains. Also provided are encoding nucleic acids, genetic constructs, host cells expressing the PorA constructs and compositions, kits and methods for detection and treatment of Neisseria meningitidis infections.