COMPARISON OF REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION, ENZYME-LINKED-IMMUNOSORBENT-ASSAY AND VIRUS ISOLATION FOR THE ROUTINE DIAGNOSIS OF FOOT-AND-MOUTH-DISEASE

A reverse transcription polymerase chain reaction (RT-PCR) method was compared with virus isolation in cell culture and the antigen detectio n ELISA for the primary diagnosis of foot-and-mouth disease (FMD) on 1 66 clinical samples from the field. Eighty samples were positive by vi rus isolation/ELISA and 78 by RT-PCR. The RT-PCR detected FMD viral RN A in 11 of the 86 samples assessed as negative by virus isolation/ELIS A but conversely failed to diagnose 13 samples identified as positive by the latter procedures. This RT-PCR is not serotype-specific so a cD NA product is indicative of the presence of FMD viral RNA only. Confir mation of the specificity of the cDNA product and the identification o f the serotype requires nucleotide sequence analysis. The value of the RT-PCR is that it can rapidly facilitate the molecular analysis of fi eld isolates and thus provide important epidemiological information re garding the source of outbreaks. However, it is a sophisticated techni que requiring specialised equipment, expertise and refined reagents an d has to be used in conjunction with current procedures for FMD diagno sis. (C) 1998 Elsevier Science B.V. All rights reserved.