Viral Load, Detection Rate and Sensitivity of Nasopharyngeal and Oropharyngeal Swab Sampling for Diagnosis of COVID-19
DOI:
https://doi.org/10.33102/uij.vol33no3.319Keywords:
COVID-19, nasopharyngeal swab, oropharyngeal swab, nasal swab, throat swabAbstract
The rapid spread of the COVID-19 pandemic has led to a major public health crisis. Accurate screening methods for COVID-19 infection is essential and crucial for case detection, isolation, prevention and control of the current pandemic. At present, nasopharyngeal and oropharyngeal swabs are typically used as the method of choice for the diagnosis of SARS-CoV-2 infection. We carried out a review on the accuracy of the two different sampling sites, the nasopharyngeal and oropharyngeal swab sampling, focusing on the viral load, detection of positive cases and sensitivity in real-time polymerase chain reaction (RT-PCR) assay in diagnosing COVID-19. A total of 25 articles related to the topic were selected out of 5221 articles searched online using Scopus, PubMed and Medline, Embase, Web of Science, and Google scholar with the keywords COVID-19, SARS-CoV-2, nasopharyngeal swab, oropharyngeal swab, nasal swab and throat swab. All full text original articles were obtained and reviewed. Nasopharyngeal swab had significantly higher SARS-CoV-2 load than oropharyngeal swab (mean Ct value ranging from 24.3-37.8, higher detection of positive rate (highest rate 62.5%) and sensitivity (highest sensitivity 98.3%, P<0.05) in RT-PCR assay compared to oropharyngeal swab. Based on the scientific literature review, both nasopharyngeal and oropharyngeal swabs were reported to have 30% probability of yielding false negative results; thus clinically suspicious patients with negative results should be viewed with concern. In conclusion, although several methods of COVID-19 screening and type of specimen are available, nasopharyngeal swab is the best option for large scale screening as it yields significantly higher viral load, higher detection of positive rate among cases and higher sensitivity in RT-PCR assay compared to oropharyngeal swab in detecting SARS-CoV-2.
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Bwire, G. M., Majigo, M. V., Njiro, B. J., & Mawazo, A. (2021). Detection profile of SARS‐CoV‐2 using RT‐PCR in different types of clinical specimens: A systematic review and meta‐analysis. Journal of medical virology, 93(2), 719-725.
Calame, A., Mazza, L., Renzoni, A., Kaiser, L., & Schibler, M. (2021). Sensitivity of nasopharyngeal, oropharyngeal, and nasal wash specimens for SARS-CoV-2 detection in the setting of sampling device shortage. European Journal of Clinical Microbiology & Infectious Diseases, 40(2), 441-445.
Chan, J. F. W., Yuan, S., Kok, K. H., To, K. K. W., Chu, H., Yang, J., ... & Yuen, K. Y. (2020). A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. The lancet, 395(10223), 514-523.
Chen, Y., Chen, L., Deng, Q., Zhang, G., Wu, K., Ni, L., ... & Cheng, Z. (2020). The presence of SARS‐CoV‐2 RNA in the feces of COVID‐19 patients. Journal of medical virology, 92(7), 833-840.
Guan, W. J., Ni, Z. Y., Hu, Y., Liang, W. H., Ou, C. Q., He, J. X., ... & Zhong, N. S. (2020). Clinical characteristics of coronavirus disease 2019 in China. New England journal of medicine, 382(18), 1708-1720.
Hernes, S. S., Quarsten, H., Hagen, E., Lyngroth, A. L., Pripp, A. H., Bjorvatn, B., & Bakke, P. S. (2011). Swabbing for respiratory viral infections in older patients: a comparison of rayon and nylon flocked swabs. European journal of clinical microbiology & infectious diseases, 30(2), 159-165.
Kim, C., Ahmed, J. A., Eidex, R. B., Nyoka, R., Waiboci, L. W., Erdman, D., ... & Katz, M. A. (2011). Comparison of nasopharyngeal and oropharyngeal swabs for the diagnosis of eight respiratory viruses by real-time reverse transcription-PCR assays. PloS one, 6(6), e21610.
Lieberman, D., Lieberman, D., Shimoni, A., Keren-Naus, A., Steinberg, R., & Shemer-Avni, Y. (2009). Identification of respiratory viruses in adults: nasopharyngeal versus oropharyngeal sampling. Journal of clinical microbiology, 47(11), 3439-3443.
Li, L., Chen, Q. Y., Li, Y. Y., Wang, Y. F., Yang, Z. F., & Zhong, N. S. (2013). Comparison among nasopharyngeal swab, nasal wash, and oropharyngeal swab for respiratory virus detection in adults with acute pharyngitis. BMC infectious diseases, 13(1), 1-5.
Li, Z., Yi, Y., Luo, X., Xiong, N., Liu, Y., Li, S., ... & Ye, F. (2020). Development and clinical application of a rapid IgM‐IgG combined antibody test for SARS‐CoV‐2 infection diagnosis. Journal of medical virology, 92(9), 1518-1524.
Lin, C., Xiang, J., Yan, M., Li, H., Huang, S., & Shen, C. (2020). Comparison of throat swabs and sputum specimens for viral nucleic acid detection in 52 cases of novel coronavirus (SARS-Cov-2)-infected pneumonia (COVID-19). Clinical Chemistry and Laboratory Medicine (CCLM), 58(7), 1089-1094.
Liu, R., Han, H., Liu, F., Lv, Z., Wu, K., Liu, Y., ... & Zhu, C. (2020). Positive rate of RT-PCR detection of SARS-CoV-2 infection in 4880 cases from one hospital in Wuhan, China, from Jan to Feb 2020. Clinica Chimica Acta, 505, 172-175.
Loeffelholz, M. J., & Tang, Y. W. (2020). Laboratory diagnosis of emerging human coronavirus infections–the state of the art. Emerging microbes & infections, 9(1), 747-756.
Patel, M. R., Carroll, D., Ussery, E., Whitham, H., Elkins, C. A., Noble-Wang, J., ... & Brooks, J. T. (2021). Performance of Oropharyngeal Swab Testing Compared With Nasopharyngeal Swab Testing for Diagnosis of Coronavirus Disease 2019—United States, January 2020–February 2020. Clinical Infectious Diseases, 72(3), 482-485.
Peiris, J. S. M., Chu, C. M., Cheng, V. C. C., Chan, K. S., Hung, I. F. N., Poon, L. L., ... & HKU/UCH SARS Study Group. (2003). Clinical progression and viral load in a community outbreak of coronavirus-associated SARS pneumonia: a prospective study. The Lancet, 361(9371), 1767-1772.
Peter, Ek., Böttiger, B., Dahlman, D., Hansen, K. B., Nyman, M., & Nilsson, A. C. (2019). A combination of naso-and oropharyngeal swabs improves the diagnostic yield of respiratory viruses in adult emergency department patients. Infectious Diseases, 51(4), 241-248
Reuters.com (25th January, 2020).Malaysia confirms first cases of coronavirus infection.. Available: https://www.reuters.com/article/china-healthmalaysiaidUSL4N29U03A.
Wang, H., Liu, Q., Hu, J., Zhou, M., Yu, M. Q., Li, K. Y., ... & Xu, S. Y. (2020). Nasopharyngeal swabs are more sensitive than oropharyngeal swabs for COVID-19 diagnosis and monitoring the SARS-CoV-2 load. Frontiers in medicine, 7, 334
Wang, K., Zhang, X., Sun, J., Ye, J., Wang, F., Hua, J., ... & Wu, X. (2020). Differences of severe acute respiratory syndrome coronavirus 2 shedding duration in sputum and nasopharyngeal swab specimens among adult inpatients with coronavirus disease 2019. Chest, 158(5), 1876-1884.
Wang, X., Tan, L., Wang, X., Liu, W., Lu, Y., Cheng, L., & Sun, Z. (2020). Comparison of nasopharyngeal and oropharyngeal swabs for SARS-CoV-2 detection in 353 patients received tests with both specimens simultaneously. International Journal of Infectious Diseases, 94, 107-109.
Wang, W., Xu, Y., Gao, R., Lu, R., Han, K., Wu, G., & Tan, W. (2020). Detection of SARS-CoV-2 in different types of clinical specimens. Jama, 323(18), 1843-1844
Winichakoon, P., Chaiwarith, R., Liwsrisakun, C., Salee, P., Goonna, A., Limsukon, A., & Kaewpoowat, Q. (2020). Negative nasopharyngeal and oropharyngeal swabs do not rule out COVID-19. Journal of clinical microbiology, 58(5).
World Health Organization (2020) Coronavirus disease (COVID-19). [Online].Available: https://www.who.int/emergencies/diseases/novel-coronavirus-2019.
Wölfel, R., Corman, V. M., Guggemos, W., Seilmaier, M., Zange, S., Müller, M. A., ... & Wendtner, C. (2020). Virological assessment of hospitalized patients with COVID-2019. Nature, 581(7809), 465-469.
Yang, Y., Yang, M., Shen, C., Wang, F., Yuan, J., Li, J., ... & Liu, Y. (2020). Laboratory diagnosis and monitoring the viral shedding of 2019-nCoV infections. MedRxiv
Yu, F., Yan, L., Wang, N., Yang, S., Wang, L., Tang, Y., ... & Zhang, F. (28). March 2020. Quantitative detection and viral load analysis of SARS-CoV-2 in infected patients. Clin Infect Dis, 71(15), 793-798
Xiao, A. T., Tong, Y. X., Gao, C., Zhu, L., Zhang, Y. J., & Zhang, S. (2020). Dynamic profile of RT-PCR findings from 301 COVID-19 patients in Wuhan, China: a descriptive study. Journal of Clinical Virology, 127, 104346.
Zhang, H., Chen, M., Zhang, Y., Wen, J., Wang, Y., Wang, L., ... & Zhang, F. (2020, October). The yield and consistency of the detection of SARS-CoV-2 in multiple respiratory specimens. In Open forum infectious diseases (Vol. 7, No. 10, p. ofaa379). US: Oxford University Press.
Zhou, F., Yu, T., Du, R., Fan, G., Liu, Y., Liu, Z., ... & Cao, B. (2020). Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. The lancet, 395(10229), 1054-1062.
Zou, L., Ruan, F., Huang, M., Liang, L., Huang, H., Hong, Z., ... & Wu, J. (2020). SARS-CoV-2 viral load in upper respiratory specimens of infected patients. New England Journal of Medicine, 382(12), 1177-1179.
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Copyright (c) 2021 Eyzawiah Hassan, Nuralia Akma Mohamad Mustafa, Nor Azirah Salahuddin, Siti Asmat Md Arepen
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