Hanayuki Okura and Akifumi Matsuyama
Rapid microbial tests ensure testing in rapid and accurate manners at reasonable costs. The ideal test should achieve detection of certain types of microorganisms that are undetected by the pharmacopoeia-defined sterility tests and its accuracy should be confirmed by regulatory authorities. The use of pharmacopoeia sterility tests is limited since they can detect only microorganisms that are viable only in specified media. A rapid test that can detect viable bacteria and microbes that cannot be cultured and never fails in bacterial detection, should appeal to the regulatory authorities. In the agar mediumculture system employed in the pharmacopoeia-microbial test, the test results may be erroneously false negative when the viable bacteria fail to grow under the defined incubation conditions, when inhibitors are present in the test sample, or when scientific approaches are not available to differentiate negative from false negative results. On the other hand, rapid microbial tests with false positive results due to noise caused by detection principle, measurement device, or non-biologic positive substance, imposes huge industrial challenges. In this review, we discuss the rapid microbial tests classified according to various systems for detection of microorganisms and their application, and then introduce some commercial applications of existing devices for detection of microorganisms and provide details of microbial test features, and compare the purposes of the microbial tests.