Single-site localization of rabies virus: impact on laboratory reporting policy.

Information accumulated by our rabies laboratory during 1977-1979 was retrospectively analyzed for patterns of rabies localization in brain. Of the 1,730 specimens reported positive during that period, 37 were positive at a single site, 27 involving only the cerebellum. Therefore, we recommend that those laboratories which offer the fluorescent rabies antibody test (FRA) examine both cerebellum and hippocampus. Definitive reports based on the FRA should be offered only when both sites have been shown negative for viral particles, or when a positive result is unquestionable.