the present disclosure relates to compositions , methods , systems and kits for the detection of microorganisms of the shigella species , including s . flexneri , s . dysenteriae , s . sonnei , and s . boydii . the disclosure relates to recombinant phage operable to infect a s . flexneri microorganism , the phage comprising a detectable reporter . detection systems of the disclosure may comprise a phage operable to infect a s . flexneri microorganism , and may comprise a reporter nucleic acid expressible upon infection of a s . flexneri microorganism by the phage . the system may be operable to detect the expression of the reporter . a detectable reporter may comprise any gene having bioluminescent , colorimetric and / or visual detectability . live and infectious s . flexneri microbes may be detected by the compositions , methods , systems and kits described herein .