Specimen Requirements Selection, Collection, Transport, and Processing

New technology has expanded the selection, collection, and interpretation of test results compared to past years. Basically, the specimen requirements for cell culture-and molecular-based diagnostic tests are similar. The authors aim at defining unique and optimal specimen processing needs for each technology in this chapter. The selection of an appropriate specimen is vital to a correct test result; this includes not only the source of the specimen but also the timing and volume of collections. Information pertaining to all of these issues should be collated into comprehensive tables listing general disease categories and associated viruses, including optimal specimen types, methods of collection, methods of detection, volumes required, and containers for transport. The significance of detection of a virus may have a different level of importance depending on the time of collection. Specimens from the respiratory tract can represent almost one-half of the source material and one-third of the total viruses diagnosed in the clinical laboratory. Detection of viruses from blood specimens provides evidence of disseminated, invasive infections which may lead to systemic disease. Major diagnostic methods for detection of viral infections have been cell culture (conventional tube and shell vial), fluorescent-antibody direct staining of specimen smears on slides, antigen detection by EIA, and amplification and detection of target nucleic acids by polymerase chain reaction (PCR).