Samples that showed positive results for HRV were amplified again using specific primers P1-1F and VP4/2R, located in the 59UTR and VP2 gene, respectively (Table 1) . One strain of HRV-C (N1) could not be amplified using the P1 and VP2 extreme primers and was amplified using primers in 59UTR and VP4/ VP2, respectively (Table 1 ). In brief, 2.5 ml of extracted RNA was mixed with 56 buffer and 0.4 mM dNTPs, 0.2 mM of each of the primers, and 1 ml of enzyme mix, and diethylpyrocarbonatetreated ultrapure water was added to a final volume of 25 ml. Amplification programs included reverse transcription at 50uC for 30 min, inactivation at 95uC for 15 min, followed by 40 cycles at 94uC for 30 s, 50uC for 30 s, 72uC for 70 s, and final extension at 72uC for 10 min. The amplified DNA products were detected by ethidium bromide-agarose gel electrophoresis. The lengths of P1-VP2, VP4-VP2 and P1-P3 amplicons were 924, 559 and 390 nt, respectively. DNA products were extracted from agarose gels by using QIAquick Gel Extraction Kit (Qiagen), and were ligated into pMD20-T vector (Takara Biotechnology, Dalian, China), and at least two recombinant plasmids were sequenced in Biosune Sequence Company and Life Biotechnology in Shanghai, China. Sequences of different clones of N16 and N58 showed identities for either HRV-A or HRV-B strains. More plasmids were sequenced for these strains to confirm that the two patients were originally coinfected with two different HRV species.