Sensitivity of agar overlay method for the recognition of enteroviruses.

COMPARISON OF THE AGAR OVERLAY TECHNIQUE WITH THE FLUID CULTURE TECHNIQUE FOR ISOLATION AND IDENTIFICATION OF ENTEROVIRUSES SHOWED THE FORMER TO BE USEFUL: (i) for isolation of enterovirus when the number of virus particles was too small to produce detectable cytopathic effect (CPE) in fluid cultures, (ii) for isolation of echovirus 22 which did not produce detectable CPE in fluid cultures, (iii) as an aid to rapid differentiation of enteroviruses, and (iv) for differentiation of viruses in mixed infections. Nonpolio enterovirus isolation experience in the New Haven area over a 4-year period is presented. It was concluded that the agar overlay technique is both useful and relatively simple for routine examination of clinical specimens in a diagnostic laboratory.