FIG. 1.

Distribution of optical density values obtained by detection of EV RNA in 54 CSF samples from patients with aseptic meningitis. RNA detection was by a new one-step PCR method (Penter RT-PCR) with colorimetric microwell detection assay. The dashed line represents the mean OD value (mean OD ± standard deviation, 0.13 ± 0.05) below which the assay was interpreted as negative (cutoff value). •, OD values obtained from EV culture-negative CSF specimens (n = 26); ○, OD values obtained from CSF samples negative by cell culture and in-house RT-PCR assay (n = 2); ▴, OD values obtained from EV culture-positive CSF samples (n = 28).