A collaborative study of an experimental kit for rapid rabies enzyme immunodiagnosis (RREID).

Six laboratories took part in a study to assess an experimental kit for the diagnosis of rabies using the rapid rabies enzyme immunodiagnosis (RREID) technique. The test is based on the immunocapture of rabies antigens present in homogenized brain specimens, followed by enzyme immunoassay. A total of 1253 specimens from various geographical locations and 27 animal species were tested with the RREID technique, and also with the fluorescent antibody test (FAT), which was used as a reference method. For 1220 specimens the results in RREID and FAT were the same (651 positive and 569 negative-concordance: 97.4%). However, the RREID technique appeared to be less sensitive, since 22 (3%) of the 673 specimens that were positive with FAT were negative with RREID. The RREID test is therefore specific and convenient and is a useful tool for epidemiological studies and for laboratories not equipped with an ultraviolet microscope.