[Application of reverse transcription-polymerase chain reaction in rapid diagnosis and serotype identification of dengue virus infections].

RT-PCR was developed for the amplification of partial E genome fragment from four dengue serotypes. Of the six oligonucleotide primers designed one was shared by dengue virus type 1 and type 2, and one by type 3 and type 4. Each of the other four primers was type specific. Amplified products with 240, 150, 333 and 421 bp, respectively were identified by electrophoresis on 2% agarose gel and digestion with restriction enzyme Hind III. RT-PCR can detect dengue viral RNA from at least 5TCID50 virus, which was confirmed by detection of serial dilutions of culture supernatants. RT-PCR was also applied to serum samples from 60 acute patients. The findings showed that RT-PCR was of the same specificity as isolation of virus, followed by indirect fluorescent antibody tests. RT-PCR was more sensitive than cell culture and can be used for the rapid diagnosis and serotype identification of dengue virus infections.