Application of Reverse Transcriptase-Polymerase Chain Reaction for Serotype Determination of Dengue Virus Strains Isolated in North Vietnam, 1991 to 1993

Reverse transcriptase-polymerase chain reaction (RT-PCR) was ap- plied to determine serotypes of 20 dengue virus strains isolated in north Vietnam in the years of 1991 and 1993. There were 10 strains of dengue type 1 (D1), 9 strains of dengue type 2 (D2) and a single strain of dengue type 4 (D4), respective- ly. The results completely agreed with the serotypes determined by the im- munofluorescent staining (IFA) of the infected cells using dengue type-specific monoclonal antibodies.