neisseria subflava neisseria subflava neisseria subflava is a common inhabitant found in the human upper respiratory tract. it is a gram-negative diplococcus. it produces a positive result of blue when put through the oxidase test. it is considered non-pathogenic, although in rare case it can be the causative agent of postoperative meningitis (after a neurological surgery), which is called surgical site infection (ssi). neisseria subflava scientific classification domain: bacteria phylum: pseudomonadota class: betaproteobacteria order: neisseriales family: neisseriaceae genus: neisseria species: n. subflava binomial name neisseria subflava(flügge, 1886) trevisan, 1889