Published: 2021-04-28

Feasibility of sputum testing for detection of COVID-19

Arvind Sharma, Tej Pratap Singh


For the prevention of COVID-19 spread, early and accurate detection is important. Specimens are collected through respiratory mucosal surfaces with nasopharyngeal or oropharyngeal swabs, from infected patients are highly complex. Sputum testing could preferably be a more convenient technique for the detection of COVID-19 as being noninvasive method, which could easily be collected by having a patient cough deeply to produce and expel phlegm which could be in compliance to patient in comparison to Nasopharyngeal swab (NPS). Consequently, broader testing than the current methods of nasal or throat swabs will significantly increase the number of people screening, leading to more effective control of the spread of COVID-19. Nonetheless, a comparison of the saliva-based assay with current swab test is needed to understand what and how we can benefit from this newly developed assay. Therefore, in this review article, we aimed to summarize the feasibility of sputum testing in relation to Covid-19. Any implementation of clinical sampling for diagnosis should take into considerations of the sensitivity of assays, risks to healthcare professionals, and global shortage of equipment.


COVID-19, SARS-CoV-2, Sputum sample, Sputum testing

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