Human enterovirus isolates from an outbreak typed using heteroduplex mobility analysis.

Genotyping and serotyping of enteroviruses is important for epidemiological, prognostic, and therapeutic reasons. In this study clinical isolates of enterovirus 71 during an outbreak of childhood meningoencephalitis in Sydney, Australia were identified using heteroduplex mobility analysis (HMA) of products from RT-PCR amplification of the 5' untranslated region. Five enterovirus 71 isolates shared identical heteroduplex patterns and nucleotide sequences in the 5' untranslated region. A sixth isolate exhibited minor differences in heteroduplex pattern and sequencing confirmed the isolate varied by 1% at the nucleotide level. The use of multiple reference strains and the analysis of heteroduplex patterns increased the confidence of isolate identification, and allowed identification of strain variation which could be subsequently further analyzed using sequencing. HMA can be used to accurately distinguish identical and variant isolates derived from sporadic cases and clustered infections with enteroviruses, including those causing serious infections.