Rapid detection of hepatitis C virus using recombinase polymerase amplification

Molecular Point-of-Care Testing for Hepatitis C: Available Technologies, Pipeline, and Promising Future Directions

Hepatitis C virus (HCV) remains a major public health problem, despite the availability of effective treatments. In many areas, the ability to diagnose HCV infection at the point of care is key to scaling up access to care and treatment. To achieve this, an accurate, easy-to-use, and affordable diagnostic tool is required-this would enable decentralized testing and the creation of one-stop centers to eliminate gaps in the care cascade, which would help reach the millions of people with undiagnosed HCV infection in low- and middle-income countries and high-risk populations in high-income countries. In this review, we examine the current state of point-of-care molecular technologies, the advantages and limitations of currently available devices (both near- and true-point-of-care), the potential of molecular testing to transform diagnostic medicine in the future, and the challenges that need to be addressed for broader adoption of this technology in routine clinical practice.

Biosensor-based multiple cross displacement amplification platform for visual and rapid identification of hepatitis C virus

Hepatitis C remains a global health problem, especially in poverty-stricken areas. A rapid and sensitive point-of-care (POC) diagnostic tool is critical for the early detection and timely treatment of hepatitis C virus (HCV) infection. Here, for the first time, we reported a novel molecular diagnostic assay, termed reverse transcription multiple cross displacement amplification integrated with a gold-nanoparticle-based lateral flow biosensor (RT-MCDA-AuNPs-LFB), which was developed for rapid, sensitive, specific, and visual identification of HCV. HCV-RT-MCDA induced rapid isothermal amplification through a specific primer set targeting the 5'untranslated region gene from the major HCV genotypes 1b, 2a, 3b, 6a, and 3a that are prevalent in China. The optimal reaction temperature and time for RT-MCDA-AuNPs-LFB were 68°C and 25 min, respectively. The limit of detection of the assay was 10 copies per test, and the specificity was 100% for the experimental strains. The whole detection procedure, including crude nucleic acid isolation (~5 min), RT-MCDA (68°C, 25 min), and visual AuNPs-LFB result confirmation (less than 2 min), was performed within 35 min. The preliminary results indicated that the HCV-RT-MCDA-AuNPs-LFB assay could be a valuable tool for sensitive, specific, visual, cost-saving, and rapid detection of HCV and has potential as a POC diagnostic platform for field screening and early clinical detection of HCV infection.

Point-of-Care Testing for Hepatitis Viruses: A Growing Need

Viral hepatitis, caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV), is a major global public health problem. These viruses cause millions of infections each year, and chronic infections with HBV, HCV, or HDV can lead to severe liver complications; however, they are underdiagnosed. Achieving the World Health Organization's viral hepatitis elimination goals by 2030 will require access to simpler, faster, and less expensive diagnostics. The development and implementation of point-of-care (POC) testing methods that can be performed outside of a laboratory for the diagnosis of viral hepatitis infections is a promising approach to facilitate and expedite WHO's elimination targets. While a few markers of viral hepatitis are already available in POC formats, tests for additional markers or using novel technologies need to be developed and validated for clinical use. Potential methods and uses for the POC testing of antibodies, antigens, and nucleic acids that relate to the diagnosis, monitoring, or surveillance of viral hepatitis infections are discussed here. Unmet needs and areas where additional research is needed are also described.

Rapid detection of goose astrovirus genotypes 2 using real-time reverse transcription recombinase polymerase amplification

BACKGROUND

Goose astrovirus (GoAstV) is an important pathogen that causes joint and visceral gout in goslings. It has been circulating in many provinces of China since 2017. Goose astrovirus genotypes 2 (GoAstV-2) is the main epidemic strain, and its high morbidity and mortality have caused huge economic losses to the goose industry. An accurate point-of-care detection for GoAstV-2 is of great significance. In this study, we developed a real-time reverse transcription recombinase polymerase amplification (RT-RPA) method for the on-site detection of GoAstV-2 infection.

RESULTS

The real-time RT-RPA reaction was carried out at a constant temperature of 39 °C, and the entire detection time from nucleic acid preparation to the end of amplification was only 25 min using the portable device. The results of a specificity analysis showed that no cross-reaction was observed with other related pathogens. The detection limit of the assay was 100 RNA copies/μL. The low coefficient of variation value indicated excellent repeatability. We used 270 clinical samples to evaluate the performance of our established method, the positive concordance rates with RT-qPCR were 99.6%, and the linear regression analysis revealed a strong correlation.

CONCLUSIONS

The established real-time RT-RPA assay showed high rapidity, specificity and sensitivity, which can be widely applied in the laboratory, field and especially in the resource-limited settings for GoAstV-2 point-of-care diagnosis.