Appropriate specimens have to be obtained at the right time and transported rapidly to the laboratory to derive the full benefit of virological tests. If the clinician is not completely comfortable in choosing tests, the virologist should be consulted. If this is not possible, relevant clinical information clearly indicated on the requisition will help the virologist to determine appropriate tests, once the specimen has reached the laboratory. This information will also be important for the interpretation of laboratory findings. Such information includes clinical symptoms and signs, date of onset of disease, recent vaccinations, and immunestatus of the patient. If virus serology is requested, the laboratory needs to know whether blood or blood products have been given recently. ​

Thus, meaningful laboratory service depends upon collaboration between the clinician and the virologist. Isolation of a virus does not prove that the virus is the cause of the clinical condition. CMV, for example, is excreted in the nasopharynx of approximately 25 per cent of healthy day-care age children. A concomitant presence of CMV IgM antibodies would support the evidence of a causal connection.

 By contrast, isolation of virus from CSF is usually diagnostic whatever the antibody findings. The mere demonstration of a high antibody concentration is of limited diagnostic value and must be evaluated in relation to the clinical problem. The use of virus-specific IgM determination is helpful in diagnosis of primary viral disease using a single-serum specimen. The virologist will be able to guide as to the appropriate use of virus serology and help interpret difficult serology results in cerebrospinal fluid, fetal blood as well as in immuno-supressed patients and/or blood product recipients and other complicated diagnostic situations.

 The introduction of rapid diagnostic tests in the virus laboratory, where results are available within a day has enhanced the role of the diagnostic virus laboratory, a situation that will be increasingly important with the ongoing development of new safe antiviral drugs.