Wastewater-Based Epidemiology to monitor COVID-19 outbreak: Present and future diagnostic methods to be in your radar

Abstract

The WHO has declared the COVID-19 epidemic on January 31, 2020. This virus has infected millions of people worldwide in just a few months. Shortly afterwards, the National Medical Products Administration (NMPA) announced nucleic acid testing as the gold standard for virus detection. Antibody testing is used as well as a supplementary test for suspected cases where nucleic acid detection was negative. In short, nucleic acid-based polymerase chain reaction (PCR) is the mainstream detection method for clinical samples as well as for the detection of SARS-CoV-2 in wastewaters. First data collected around the globe were reported in the last few months being part of the so-called Wastewater-Based Epidemiology (WBE) approach. Selection of concentration methods and primers, laboratory inter-comparison and various modalities of PCR detection of the virus in complex wastewater matrices were flagged up as main bullets that require urgent improvement. Novel approaches to enhance sensitivity, speed and automate streamlined virus detection will be discussed here as well. This list comprises devices mainly used for clinical purposes like Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR), Digital PCR, Lab-on-a-chip (LOC) and related platforms as well as Biosensors. The last part will be devoted to the identification of biomolecules to target Covid-19 outbreak based on inflammatory response biomarkers among others. To this end this opinion paper brings for discussion the issue of PCR detection and its limitations as well as new diagnostic methods in WBE.

Keywords: Biomarkers; Biosensors; COVID-19; Lab-on-a-chip (LOC); SARS-CoV-2; Wastewater-based epidemiology.

Fig. 1

The LionX Systems for NA-Based Virus Detection (Reproduced with permission from Quin et al., 2020 ([28]).

Fig. 2

(a) Synthetic Route for Antibody-Modified Fe3O4@Ag Magnetic Tags and (b) Schematic Diagram of the Magnetic SERS Strip for Detecting Two Respiratory Viruses-Reproduced with permission from Chongwen Wang et al., 2019 [32].

Fig. 3

Schematic diagram of COVID-19 FET sensor operation procedure. Graphene as sensing material is selected and SARS-CoV-2 spike antibody is conjugated onto the graphene sheet via 1-pyrenebutyric acid n hydroxysuccinimide ester, which is an interfacing molecule used as a probe linker. Reproduced with permission from (Seo et al., 2020 [31]).