National Recommendations from the NRC Rabies, WHO-CC for Reference and Research on Rabies, France, Concerning Biological Samples Collected for Diagnosis of Human Rabies.

aA minimum of three serially collected saliva samples and one skin biopsy from the nape of the neck are required for intra-vitam diagnosis of human rabies. This permits a sensitivity of 100% in patients presenting with encephalitic rabies (≥98% with skin biopsy alone and 100% with serial saliva samples). Skin biopsy samples can be collected irrespective of the time after the onset of symptoms. Analysis of additional samples may be advantageous. It includes RNA detection in serially collected urine and CSF samples, and rabies antibody measurement in serum and CSF. Rabies antibody detection is variable but increases with time after onset of symptoms (>8 days) and can be informative with atypical or non-classical rabies. After collection, all samples have to be stored at −20°C/−80°C before shipment. Storage at +4°C or on ice should not exceed a few hours (FAT, fluorescent antibody test; RFFIT, rapid fluorescent focus inhibition test; RTCIT, rapid tissue culture infection test; RT-hnPCR, reverse transcription hemi-nested polymerase chain reaction; WELYSSA, ELISA dedicated to lyssavirus antigen detection.