Traditional methods for pathogen detection are often expensive and time-consuming and requires a well-equipped laboratory. Here we present a low-cost, deployable paper-based biosensor device for rapid analysis of pathogens for a wide range of application including rapid diagnosis of infectious disease (such as SARS-CoV-2) and wastewater surveillance for public health. The paper microfluidic device was wax printed with hydrophobic and hydrophilic layer to enable sample processing by folding and unfolding the device. A reverse transcription loop-mediated isothermal amplification (RT-LAMP), together with CRISPR/Cas assay were designed, optimised and integrated into the paper microfluidic device, which shows a comparative sensitivity and specificity. The test results could be read by the naked eye or quantified using a mobile phone camera, as demonstrated for malaria testing in Africa and veterinary diagnosis in an Indian local farm. Furthermore, we show the device for wastewater surveillance, which has emerged as a new monitoring mechanism for early warning of pandemic within population and provides complementary data sets for clinical diagnosis. The device was demonstrated for the field testing in a local quarantine hotel, providing a sample-to-results within less than 1 hours turnround, which is currently developing to trace the source of hotspots for early warning of pandemic within a UK national wastewater surveillance programme.

Learning Objectives:

1. Discuss paper microfluidic device for rapid diagnosis.

2. Discuss molecular diagnosis with isothermal amplification and the assay coupled with CRISPR/Cas.

3. Discuss infectious disease diagnosis and wastewater surveillance for public health.