COVID-19 is a virus of the species of the Family coronaviridae known as as SARS-COV-2. This virus is easily contracted and/transmitted from an infected person to another healthy individual and has continued to spread rapidly. The aim of this review is to identify laboratory methods used in the diagnosis of COVID-19 infection. COVID-19 test are aimed at detecting active infection, or past infection, or an immunization so as to treat and curb the further spread of the virus. The initial viral detection is typically carried out with the upper respiratory tract (URT) sample. Repeated testing is particularly helpful and essential if a patient has a clinical appearance of viral pneumonia, radiographic results consistent with pneumonia and/or a history of potential exposure. The Centre of Disease Control and Prevention, CDC recommends the collection of specimens from the lower respiratory tract, upper respiratory tract, and the blood. The lower respiratory tract sample includes; the sputum, broncheoalveolar lavage, bronchial wash, tracheal aspirate, and pleural fluid. The upper respiratory tract specimens include; the nasopharyngeal swab, and oropharyngeal swab (NP/OP swabs). Some laboratory techniques developed and in use for the detection of Covid-19 are; nucleic acid amplification tests (NAATs), antibody detection, and viral antigen detection. The role of the laboratory assay in diagnosis of COVID-19 infection or disease cannot be under-estimated, timing and site of specimen collected must be followed by adequate professional training to ensure result accuracy. This review provides information on available laboratory techniques for the diagnosis of the viral infection and their potential merits and limitations.
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