Japanese researchers work to refine RDV, a tool for rapid identification of pathogenic agents.
On this day, when we remember the lives lost in the terrorist attacks of September 11, 2001, we must also never forget the anthrax scare in the days that followed them.
Because, sadly, the threat posed by similar biologic attacks has hardly diminished over the past 18 years—if anything, it has only become more pronounced.
Thankfully, researchers are also working on ways to diminish the dangers posed by these threats, as evidenced by recent work out of the National Research Institute of Police Science and the Research and Education Center for Prevention of Global Infectious Diseases of Animals in Japan. At these institutions, experts have sought to further refine the rapid determination system of viral genome sequences—or RDV method—an exhaustive gene amplification approach that can be used in the rapid identification of pathogenic agents in response to bioterrorism and so-called “biocrime” events.
They published their most recent findings in the September issue of the journal Forensic Science, Medicine and Pathology (FSMP)—and the early results are promising.
“The RDV method usually requires a virus propagation step,” study co-author Junji Hosokawa-Muto told Contagion®. “In virus-rich materials, it may be possible to detect viral genes without the propagation step. In this case, we found that it can be detected more quickly.”
As Hosokawa-Moto and colleagues note, the rapid identification of pathogenic agents is vital in the event of a biologic-based attack in order to quickly facilitate appropriate treatment and, if necessary, isolation of victims. Although various methods have been used for virologic analysis of forensic samples including blood, fluids, clothes, etc, the current most commonly used approaches are molecular methods, which include virus detection by the amplification of specific genes (eg, Polymerase chain reaction) that require viral species-specific primers.
According to the authors of the FSMP paper, if the viral species “cannot be readily assumed,” identification… may be “extremely time-consuming and labor-intensive.” The RDV method was developed to mitigate these issues through the detection of “species-independent viruses,” without primers, which allows for rapid detection of unidentified viral genome sequences, usually within 2 days—often less.
To test the approach both with and without the time-consuming viral propagation step, Hosokawa-Muto et al tested for pathogenic virus genes in fluid swab samples from a young (16-day-old) cat that died after a suspected viral infection. Via the RDV method, the authors identified nucleotide sequences of feline herpesvirus and feline calicivirus, findings that were later confirmed via direct sequencing.
Clinically, the viability of RDV has important implications in the response to bioterrorism/biocrime, according to Hosokawa-Muto and colleagues, in that it could serve as an efficient and affordable tool that can quickly identify pathogens used in these attacks, particularly in settings in which so-called next-generation sequencing (NGS) is not yet available. However, the technique may also be used for more day-to-day functions, such as in the investigation of the cause of viral illness of unknown etiology (eg, sudden infant death), they added.
“I hope the RDV method will be used in laboratories that do not yet have NGS,” Hosokawa-Muto explained. “We are currently exploring other rapid detection methods.”
If only they—or someone else—could invent a world in which they wouldn’t be necessary.