The direct identification of the virus genome from clinical samples by molecular technology is one of the most significant discoveries in the 21st century. Nucleic acid amplification techniques (e.g., PCR), nuclear acid sequence-based amplification (NASBA), and Lawrence Livermore Microbial Detection Array (LLMDA), are undoubtedly the leading technologies for rapid detection and identification of most known human viruses. PCR, an extremely sensitive detection method, can amplify a specific region of DNA sequence by 106 times in vitro.