The diagnostic kit plays a vital role in curbing the spread of novel coronavirus. Rapid and accurate diagnosis of infected people will help to reduce the panic situation.
After the major outbreak in the European nations and the United States of America, the WHO importuned the world “test, test, and test” as much possible. The importance and multifold increase in the demand for the diagnostic kit resulted in over 200 companies and researchers around the world developing rapid and accurate diagnostic kits for pneumonia ‘SARS-CoV-2’.
Nucleic acid-based molecular diagnosis (RT-PCR), antibodies detection, and lung analysis using CT-Scan are being considered for the diagnosis. Amidst, the RT-PCR test provides exact information and identifies the infection at the early stage, and hence, recognized it as a gold standard. Antibodies test and CT-Scan analysis are the secondary protocol, both the methods are used to find the infection after the proliferation of viruses in the human body. Hence, it leads to a lack of accuracy because of many governing factors in the human body.
The diagnosis process of the nucleic acid-based test (RT-PCR) follows three stages:
- Extraction of RNA from the sample and conversion to DNA (reverse transcriptase, RT)
- Amplification or multiplying the DNA (real-time polymerase chain reaction, PCR)
- Identification of specific genes related to SARS-CoV-2 (fluorescence absorbance)
Steps one and two require maximum time for the chemical reactions. The extracted RNA is reverse transcribed into DNA using reverse transcriptase process. Later, PCR is used to amplify the viral DNA through 20-30 cycles of annealing (50-60°C) and cooling process. The time required to extract RNA and developing copies is 6 hours for the qualitative analysis of SARS-CoV-2 genes.
In 2003, it took six months for developing the SARS diagnostic kit. Now in 2020, within a week’s time, we have developed the RT-PCR-based COVID-19 diagnostic test kit. It is the evidence of technological advances and endeavors of scientific researchers.
Because of the need for the fast and accurate test kit to identity the SARS-CoV-2 infection, scientists are working hard to find the way for accelerating the detection time with accuracy. In this race, South Korea, Singapore, Taiwan, and the United States have achieved a phenomenal breakthrough by developing rapid RT-PCR test kits.
South Korea is the country that flattened the curve quickly without imposing lockdown policy. The key reason behind this is the development of the test kit and extensive diagnosis.
Seegene, the global leader in multiplex molecular diagnostics developed the COVID-19 test kit called “Allplex 2019-nCoV Assay“. It has accounted for 80% of tests in South Korea. Most of the labs target one or two from the three types of genes (RdRP, N, and E) associated with the SARS-CoV-2. But, Allplex 2019-nCoV Assay offers unique technology for the simultaneous detection of all three genes in one analysis. Detection of all three genes ensures the result more confidently to consider in the pandemic wave. The identifications of one or two targets might cause false negatives, which could deteriorate the spread control.
The Seegene scientists have developed a process to amplify the DNA in 90 minutes. It reduces the processing time of the analysis. The running time inclusive of all the processes from extraction to analysis is five to six hours for handling 15,000 samples.
Taiwan’s Industrial Technology Research Institute (ITRI) introduced the nucleic acid molecular detection device and kit on April 15 with advantages of 60-minute detection time, 90% accuracy, and compact device (600 grams).
The ITRI has developed thermostatic nucleic acid amplification probe reagent kits, which reduced the time required for the qPCR process and resulted in 60 minutes of analysis time.
“ITRI’s viral nucleic acid molecule detection system can detect early infection from Day 0 to Day 7 in the incubation period when the viral concentration is still low, with 90% accuracy.” – Chii-Wann Lin, ITRI Vice President & Biomedical Technology and Device Research Laboratories General Director
United States of America
Cepheid has developed a kit “Xpert®Xpress SARS-CoV-2” for the qualitative detection of SARS-CoV-2. It is an automated molecular test to target multiple regions of the viral genome. The rapid detection of viral genome in approximately 45 minutes delivers precise results.
The device received an Emergency Use Authorization by the US Food and Drug Administration for its rapid molecular test.
Professor Jackie Ying, the head of the NanoBio lab, developed a special enzyme to photocopy the genetic material within a minute. The traditional amplification method by the heating-cooling process consumes much time. However, the new enzyme can produce millions of copies in a minute without the traditional heating-cooling process. The rapid amplification method is named as Cepat.
“We have done some preliminary clinical validation at the KK Women’s and Children’s Hospital using real patients’ samples, and found the test to be very sensitive and accurate” – Prof Jackie Ying
Prof Ying and her team are waiting for the approval of the method. After approval, this method would lead in the race of developing the point-of-care test for COVID-19 faster than the standard lab tests (45 minutes, Cepheid, USA)
The technological innovations have turned all the identification processes into a handy, speedy, accurate, in-house method for the ease of humankind and safety from the infected zone.