Rapid detection of filoviruses by real-time TaqMan polymerase chain reaction assays

Ebola virus (EBOV) and Marburg virus (MARV) are causative agents of severe hemorrhagic fever with high mortality rates in humans and non-human primates and there is currently no licensed vaccine or therapeutics. To date, there is no specific laboratory diagnostic test in China, while there is a national need to provide differential diagnosis during outbreaks and for instituting acceptable quarantine procedures. In this study, the TaqMan RT-PCR assays targeting the nucleoprotein genes of the Zaire Ebolavirus (ZEBOV) and MARV were developed and their sensitivities and specificities were investigated. Our results indicated that the assays were able to make reliable diagnosis over a wide range of virus copies from 10(3) to 10(9), corresponding to the threshold of a standard RNA transcript. The results showed that there were about 10(10) RNA copies per milliliter of virus culture supernatant, equivalent to 10,000 RNA molecules per infectious virion, suggesting the presence of many non-infectious particles. These data indicated that the TaqMan RT-PCR assays developed in this study will be suitable for future surveillance and specific diagnosis of ZEBOV and MARV in China.