Environmental DNA and RNA a key in monitoring pathogens

The disease and parasite monitoring is often curbed by the inability of traditional approaches to easily sample broad geographical areas and large numbers of individuals. This can result in patchy data that fall short of what researchers need to anticipate and address outbreaks. Writing in BioScience, Jessica Farrell, Liam Whitmore and David Duffy describes the promise of novel molecular techniques to overcome these shortcomings.

By sampling Environmental DNA and RNA, the researchers were able to determine the presence of both human and wildlife pathogens. The eDNA and eRNA approach works through the collection of a sample, whose genetic contents are then sequenced to reveal the presence and prevalence of pathogens. This eDNA or eRNA gives researchers a timely view into disease spread and helps them predict the spread of pathogens to nearby new and susceptible geographic locations and populations in advance, providing opportunities to implement prevention and mitigation strategies.

During the COVID-19 pandemic, the researchers used eRNA analysis of wastewater to track large-scale outbreaks of disease. They also found that wastewater detection of SARS-CoV-2 eRNA increased rapidly before medical detection of human outbreaks in those regions, with Environmental virus concentration peaking at the same time or before the number of human-detected cases, providing advanced warning of a surge in infected individuals. With advanced knowledge, crucial and limited medical resources can be provisioned where they will be most needed.

Major benefits of eDNA and eRNA analysis are not restricted to the detection of human pathogens; the authors described how these tools also help in understanding the presence and transmission of pathogens that hamper wildlife conservation efforts. They can help in turtle-specific DNA virus, chelonid herpesvirus 5. eDNA monitoring of this pathogen may assist researchers to analyze the disease’s spread in particular and the idea that the virus is most frequently transmitted by super spreader individuals.Farrell, Whitmore, and Duffy said that the future of the technology is bright with its potential to exceed traditional detection methods and the capacity to improve the detection and monitoring of aquatic pathogens and their vulnerable host species, including humans.