Rapid differentiation between Hantaan and Seoul viruses by polymerase chain reaction and restriction enzyme analysis.

The majority of causative strains of hemorrhagic fever with renal syndrome (HFRS) are known as Hantaan and Seoul viruses in Korea. The clinical manifestations may be indistinguishable between both viruses, although the clinical course of Hantaan virus infection is more severe than that of the Seoul virus. Therefore, the differentiation of Hantaan or Seoul virus may be important for predicting the prognosis. The primers were selected from the published sequences of the S segments of Hantaan virus strain 76-118 and Seoul virus strain SR-11, which made it possible to obtain the same size of 403 bp amplified product by reverse transcriptase polymerase chain reaction (RT-PCR) and nested PCR from both viral strains. The differentiation of the amplified products was carried out by restriction enzyme digestion. With HindIII, the 403 bp amplified product from Hantaan virus strain 76-118 was cleaved into two segments of 175 bp and 228 bp. By contrast, the 403 bp product from Seoul virus strain SR-11 was not cut by HindIII. With HinfI, the 403 bp amplified product from Hantaan virus strain 76-118 was divided into two bands of 280 bp and 60 bp on the electrophoresis. In the case of the digestion of 403 bp PCR product from Seoul virus strain SR-11 with HinfI, more than four bands (155 bp, 115 bp, 60 bp, and 32/29 bp) were observed on the 2% agarose gel electrophoresis. This rapid technique may be useful for the differential diagnosis of Asian HFRS in Korea.