Laboratory tests to detect and diagnose novel respiratory infections like SARS-CoV-2 have benefitted from new technologies like nucleic acid amplification (NAAT) (a/k/a polymerase chain reaction PCR) and next-generation sequencing. These techniques are still primarily employed in laboratory settings, although a few point-of-care (PoC) tests have been granted emergency use authorization by the FDA for use in patient care settings, under CLIA certificates of waiver.
The focus on laboratory diagnostic testing for COVID-19 should not detract from the development of PoC testing: existing and emerging trends point toward continued advances in detection, diagnosis, and management of a multitude of chronic and infectious diseases, or rule out diseases in emergency settings.
Key aspects of any effective new PoC test are portability and speed. Tests that provide results in 30 minutes or less are optimal. These may range from glucose monitoring tests that give near-instant results, to complex “lab on a chip” devices that perform reverse transcriptase-polymerase chain reaction tests. The cost effectiveness of tests is also an important factor to consider.
The use of biosensors has improved the reliability and cost effectiveness in PoC settings for the detection of novel respiratory viral infections, either by identifying antigens or by pinpointing viral DNA. Electrodes in the device cause antibodies to bind to viral samples, or cause the sample to change how it reflects light.
PoC biomarker techniques that detect signs of cancer are under development. Researchers at the University of Queensland developed a test to identify a newly discovered cancer biomarker that had up to 90% accuracy, boding well for further advances in PoC testing for cancer biomarkers.
Microfluidic chips that employ reverse transcription loop-mediated isothermal amplification (RT-LAMP) to detect a variety of respiratory viruses came into use as early as 2014 and continue to evolve, with new applications coming out in subsequent years that could detect human metapneumovirus (HMPV), Middle Eastern Respiratory Virus (MERS-CoV), and influenza A (IAV) viruses using isothermal NAAT technologies that don’t require complex, lab-based devices to work with nucleic acids extracted from tissue samples.
PoC tests for blood glucose levels have been around for a long time. Now, however, these tests can transmit results to the cloud, so patients, caregivers, and healthcare providers can share vital data to monitor patient condition and access advice online.
The 2019 Munich Symposium on PoC test devices focused attention on chronic disease management, emergency medicine, emerging analytical technologies, quality assurance, and data security. Mechanical engineering diagnostic device design companies continue to address emerging trends in PoC testing, to meet challenges in these areas and help manufacturers produce reliable, accurate, and cost-effective PoC testing devices.