The recent development of a novel coronavirus detection method by researchers at the Institute of Genomics and Integrative Biology (IGIB) and the National Centre for Disease Control (NCDC) has made headlines. The technique is based on mass spectrometry, offering a new approach to identifying the presence of SARS-CoV-2. Before diving into the specifics of this innovation, it’s essential to understand the respective roles of IGIB and NCDC.
About IGIB and NCDC
The IGIB is a premier institution within the Council of Scientific and Industrial Research (CSIR), dedicated to significant research areas including genomics, molecular medicine, and bioinformatics. It operates from New Delhi. Meanwhile, the NCDC falls under the administrative control of the Directorate General of Health Services in the Union Ministry of Health and Family Welfare.
Understanding Mass Spectrometry (MS)
Mass spectrometry (MS) is an analytical tool used to determine the elemental composition of samples, quantify the mass of particles and molecules, and elucidate their chemical structure. MS pivots on ionizing and fragmenting sample molecules in the gaseous phase. Instruments like mass spectrometers and mass spectrographs, which operate based on ion deflection by electric and magnetic fields, facilitate this technique. MS technology finds extensive use in clinical laboratories for disease screening, disease diagnosis, metabolic disorders diagnosis, drug therapy monitoring, drug toxicity identification, poisoning identification and new biomarker discovery.
New Technique for COVID-19 Detection
The newly developed technique based on mass spectrometry identifies the presence of two peptides unique to SARS-CoV-2 virus. These unique peptides are building blocks of the viral protein and are unseen in other coronaviruses or viruses. Although seven unique peptides exist in SARS-CoV-2, only two are required for rapid virus detection. One of these is a spike protein and the other, a replicase protein. These unique peptides have been identified in over 54,000 genomic SARS-CoV-2 virus sequences deposited in the GISAID public database as of 1st July 2020.
Comparison of the New Technique with RT-PCR
Contrary to the Reverse Transcription-Polymerase Chain Reaction (RT-PCR) test, this new method directly detects the virus without amplifying the RNA. This feature enables scientists to detect the peptides of SARS-CoV-2 virus even in patients who have recovered from the symptoms and have tested negative for the virus by RT-PCR – the peptides can be traced even after 14 days of initial infection.
In terms of test effectiveness, this novel technique delivers a 95% sensitivity rate and 100% specificity rate relative to RT-PCR. This performance remodels the testing landscape, which has been predominantly experiencing 20-50% false negatives with rapid antigen kits.
Furthermore, this new method guarantees faster results – detection can be completed in less than three minutes, and the entire process from sample preparation to detection takes less than 30 minutes. In comparison, RT-PCR requires a minimum of 2-5 hours, inclusive of sample transportation time.
Cost and Pooled Testing
While the initial set-up cost may seem high due to the price of a mass spectrometer, the actual per-test cost amounts to merely around Rs.100, making it cheaper than RT-PCR. Moreover, several research labs already possess the necessary mass spectrometer. Another attractive feature of this method is its compatibility with pooled testing, wherein samples from multiple individuals are mixed together for testing. If a batch returns positive, only samples from that batch are retested individually to identify the carrier of the infection. This strategy enhances cost efficiency and testing scalability. Given these advantages, this new technique can complement RT-PCR or serve as its alternative.
Different Types of Tests for Detecting COVID-19
Apart from the new mass spectrometry-based method, there are several other testing methods for detecting COVID-19, such as RT-PCR tests, rapid antigen detection tests, RTnPCR tests, Feluda tests, ELISA antibody tests, and SalivaDirect test.
