Korean Researchers Develop Dual COVID and Flu Rapid Test

Imagine the ability to test and detect COVID-19 and the flu simultaneously.

No need to imagine anymore.

Determined to overcome the challenge of diagnosing concurrent respiratory infections, researchers from Korea have developed a TwinDemic Detection (TDD) system—i.e., a point-of-care diagnostic tool that leverages a novel, non-enzymatic signal amplification method.

By testing its performance using human nasopharyngeal samples, TDD was shown to detect SARS-CoV-2 and influenza A virus simultaneously, highlighting its potential application in rapid on-site testing for a wider range of viruses.

The COVID-19 outbreak in 2019 triggered measures to raise public awareness regarding pandemics and also led to fast-tracked vaccine development. While these measures helped reduce viral transmission significantly, it also had some unintended consequences, such as an overall reduction in the spread of other viruses, leading to pauses in vaccination regimes. However, fast-mutating pathogens like viruses still pose a significant threat, with predictions of co-infections with multiple viruses causing future “twindemics” or “tripledemics.”

Reverse Transcriptase-quantitative PCRs (RT-qPCRs) are reliable disease diagnostic assays but are constrained by the use of expensive equipment and reagents, limiting their utility in resource-constrained settings. Therefore, a rapid, accurate, and sensitive molecular diagnostic tool is warranted for the simultaneous detection of multiple viruses at the point-of-care.

To address this gap, a team of scientists from the Republic of Korea, led by Professor Eunjung Kim from Incheon National University (INU), recently developed a novel TwinDemic Detection (TDD) system, designed for simultaneous detection of SARS-CoV and influenza A virus (IAV). The team’s findings were published in the Feb. 1 issue of Sensors and Actuators B: Chemical journal.

“The TDD includes a transparent poly (methyl methacrylate) microfluidic chip with hydrogel-based, enzyme-free gene detection sensors, along with a handheld fluorescence reader,” explained Prof. Kim, describing the detection system. The hydrogel chambers are embedded with customized probes to detect the two target viral pathogens: SARS-CoV-2 (CoV) and IAV. The reaction between the target viral DNA and the specific probe system amplifies the fluorescence signal.

Notably, the TDD system is easy to use, cost-effective, and has a detection limit of 0.46 picomolar (pM) for CoV and 0.39 pM for IAV. To confirm TDD’s diagnostic efficiency, 15 nasopharyngeal swabs each from healthy individuals, patients with COVID-19, and those with Flu A were tested. For COVID-19 diagnosis, the TDD system correctly predicted positive samples in 93.3% of the cases, and negative samples in 96.7% of the cases. For IAV, positive and negative samples were correctly predicted in 100% and 96.7% of the cases, respectively.

Elaborating on the prospects of the TDD system against the team’s findings, Prof. Kim said, “The application of our TDD system can be further expanded by introducing additional channels and sensing hydrogels on the microfluidic chip, as well as integrating highly sensitive nucleic acid amplification systems for simultaneous detection and differentiation of a wider range of viruses.”

Overall, this study presents and highlights the TDD system as a novel point-of-care diagnostic tool that enables an accurate and rapid on-site detection of multiple viruses simultaneously and could help clinicians make timely and appropriate treatment decisions.

References
Authors: Jaewoo Lim,^1,2 Jin Woo Ahni,² Inhee Maeng,³ Jina Lee,^1,4 Ryunhyung Kim,⁵ Byenggeol Mun,⁵ Sunjoo Kim,⁶ Hyowon Jang,¹ Taejoon Kang,^1,7 Juyeon Jung,^1,4,7 Seungjoo Haam,⁵ Eunjung Kim,^8,9* Seung Jae Oh,^3* and Eun-Kyung Lim^1,4,7*

¹ Bionanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Republic of Korea
² Medical Device Development Center, Osong Medical Innovation Foundation, Republic of Korea
³ YUHS-KRIBB Medical Convergence Research Institute, College of Medicine, Yonsei University, Republic of Korea
⁴ Department of Nanobiotechnology, KRIBB School, University of Science and Technology (UST), Republic of Korea
⁵ Department of Chemical and Biomolecular Engineering, College of Engineering, Yonsei University, Republic of Korea
⁶ Department of Laboratory Medicine, Gyeongsang National University Changwon Hospital, Republic of Korea
⁷ School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
⁸ Department of Bioengineering & Nano-bioengineering, Research Center for Bio Materials and Process Development, Incheon National University, Republic of Korea
⁹ Division of Bioengineering, Incheon National University, Incheon 22012, Republic of Korea

* Corresponding authors’ emails: [email protected] (Dr. Seung Jae Oh); [email protected] (Prof. Eunjung Kim); [email protected] (Dr. Eun-Kyung Lim)