Analytical performances of different diagnostic methods for SARS-CoV-2 virus - A review

Abstract

Covid-19 is a dreadful pandemic of the 21st century that has created fear among people, affected the whole world, and taken thousands of lives. It infects the respiratory system and causes flu-type symptoms. According to the WHO reports, 2,082,745 deaths and 96,267,473 confirmed cases were perceived all around the globe till January 22, 2021. The significant roots of transmission are inhalation and direct contact with the infected surface. Its incubation period is 2-14 days and remains asymptomatic in most people. However, no treatment and vaccine are available for the people, so preventive measures like social distancing, wearing personal protective equipment (PPE), and frequent hand-washing are the practical and only options for cure. It has affected every sector of the world, whether it is trade or health all around the world. There is high demand for diagnostic tools as high-scale and expeditious testing is crucial for controlling disease spread; thus, detection methods play an essential role. Like flu, Covid-19 is also detected through RT-PCR, as the World Health Organization (WHO) suggested, but it is time taking and expensive method that many countries cannot afford. A vaccine is a crucial aspect of eradicating disease, and for SARS-CoV-2), plasma therapy and antibiotics therapy are used in the early spreading phase. The later stage involves forming a vaccine based on spike protein, N-protein, and whole-viral antigen that effectively immunizes the population worldwide until herd immunity can be achieved. In this review, we will discuss all possible and developed techniques for identifying SARS-CoV-2 and make a comparison of their specificity, selectivity, and cost; thus, we choose an appropriate method for fast, reliable, and pocket-friendly detection.

Keywords: Biosensor; Covid-19; Lateral flow immunoassay; RT-PCR; SARS-CoV-2.

Fig. 1

A basic structure of SARS-CoV-2 virus. Spike protein and envelope protein are present on the external surface of virus and spike protein is used for receptor binding.

Fig. 2

A basic transmission route of Covid-19 virus in human. Virus binds with ACE-2 receptor on respiratory cells via spike protein which is located the surface of SARS-CoV-2 virus. A partial segment of respiratory cell is showing ACE2 receptor located in plasma membrane.

Fig. 3

A flow chart showing different detection methods for COVID-19. Serological assays are subdivided into separate types and explained with their advantage.