Laboratory Diagnosis of SARS-CoV-2 Pneumonia

Abstract

The emergence and rapid proliferation of Coronavirus Disease-2019, throughout the past year, has put an unprecedented strain on the global schema of health infrastructure and health economy. The time-sensitive agenda of identifying the virus in humans and delivering a vaccine to the public constituted an effort to flatten the statistical curve of viral spread as it grew exponentially. At the forefront of this effort was an exigency of developing rapid and accurate diagnostic strategies. These have emerged in various forms over the past year-each with strengths and weaknesses. To date, they fall into three categories: (1) those isolating and replicating viral RNA in patient samples from the respiratory tract (Nucleic Acid Amplification Tests; NAATs), (2) those detecting the presence of viral proteins (Rapid Antigen Tests; RATs) and serology-based exams identifying antibodies to the virus in whole blood and serum. The latter vary in their detection of immunoglobulins of known prevalence in early-stage and late-stage infection. With this review, we delineate the categories of testing measures developed to date, analyze the efficacy of collecting patient specimens from diverse regions of the respiratory tract, and present the up and coming technologies which have made pathogen identification easier and more accessible to the public.

Keywords: COVID-19; Ct value; NAAT; RT-LAMP; RT-PCR; antibody test; point of care testing; rapid antigen test.

Figure 1

Structure of SARS-CoV-2 virus. A—Schematic of SARS-CoV-2 virion, B—Schematic of SARS-CoV-2 genome structure. Reprinted with permission from ref. [8]. Copyright 2021 American Society for Microbiology-Journals.