Comparison and Evaluation of Real-Time Taqman PCR for Detection and Quantification of Ebolavirus

Application of multiplex realtime PCR detection for hemorrhagic fever syndrome viruses

BACKGROUND

Multiplex real-time PCR is a quick and cost effective method for detection of various gene simultaneously. HFSV (Hemorrhagic Fever Syndrome Virus) is a newly emerging infectious disease because of globalization and climate change. We tried to develop a molecular diagnostic technique for various causative viruses and evaluate its usefulness for improving public health.

METHODS

Molecular diagnostic test method that qualitatively detects viruses causing viral hemorrhagic fevers hired Taq-Man Real-time RT-PCR technique. The Ct value was experimentally observed three or more times at the RNA concentration before and after the detection limit. After designing a multiplex real-time RT-PCR test for target gene of selected 17 viruses, the detection limit for each target and the presence or absence of cross-reaction and interference reaction were evaluated to determine its availability.

RESULTS

Six kinds of viruses, including Crimean-Congo hemorrhagic fever virus, Omsk hemorrhagic fever virus, Sabia virus, Chapare virus, Yellow fever virus, and Variola virus (A4L gene, B12R gene), were able to confirm the detection limit of 0.5 copies/μl, and other Ebola virus, Marburg virus, Rift Valley fever virus, Kyasanur Forest disease virus, Junin virus, Guanarito virus, Machupo virus, Chikungunya virus, Hantavirus, Dengue virus types 1-4, and Lassa virus (L gene, GPC gene), and 11 kinds of viruses, the detection limit was confirmed at 5 copies/μl. No cross-reaction or interference between detected genes was observed.

CONCLUSION

The virus test method developed through this study using multiplex is expected to be used for public health and quarantine as a test method that can be used when a hemorrhagic fever virus of unknown cause is introduced.

Efficacy of disinfectants for inactivation of Ebola virus in suspension by integrated cell culture coupled with real-time RT-PCR

BACKGROUND

Ebola virus can be transmitted by contact with environmental surfaces (fomites) contaminated with secretions and excretions from infected individuals. Due to their potential to cause a public health emergency and the absence of efficacious drugs and vaccines, a crucial intervention may involve the use of an effective virucidal agent for disinfecting contaminated surfaces.

METHODS

In this study, the virucidal efficacy of three disinfectants against Ebola virus, Micro-Chem Plus detergent disinfectant cleaner (MCP), FWD and ethanol, was evaluated in suspension tests according to the Technical Standard for Disinfection of China. All products at different concentrations were tested with application times ranging from 15 s to 8 min by using a quantitative suspension test, and a comparative inactivation analysis was performed. A reduction in the virus titre of ≥4 log10 was regarded as evidence of virucidal activity.

RESULTS

MCP and FWD, which contain dual quaternary ammonium compounds, are highly effective at inactivating the Ebola virus within 15 s of contact time, despite a slight difference between them at lower concentrations. Similar to the results in the literature, our results confirmed the excellent virucidal activity of medical ethanol for Ebola virus, which can reduce viral titres to background levels within 15 s at a concentration of 38% (v/v).

CONCLUSION

These three disinfectants display sufficient inactivation efficacy for the Ebola virus at reasonably short contact times, which may be practically achieved in the field. The use of these disinfectants for decontamination in health care settings and laboratories could mitigate the risk of Ebola virus transmission.