Detection of SARS-CoV-2 RNA by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) on Self-Collected Nasal Swab Compared With Professionally Collected Nasopharyngeal Swab

Nusrat Mannan; Ruksana Raihan; Ummey Shahnaz Parvin; Sheikh Mohammad Fazle Akbar; Md Selim Reza; Shafiqul Islam; Joy Kundu; Abdullah Al Noman; Md Fakhruddin; Muttasim Billaha; Moniruzzaman Anik; Tanzil Hasan; Nikhil Tudu; Abdur Rahim; Farzana Mim; Mohammad Jahidur Rahman Khan

doi:10.7759/cureus.25618

Detection of SARS-CoV-2 RNA by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) on Self-Collected Nasal Swab Compared With Professionally Collected Nasopharyngeal Swab

Cureus. 2022 Jun 3;14(6):e25618. doi: 10.7759/cureus.25618. eCollection 2022 Jun.

Authors

Nusrat Mannan¹, Ruksana Raihan¹, Ummey Shahnaz Parvin¹, Sheikh Mohammad Fazle Akbar², Md Selim Reza³, Shafiqul Islam¹, Joy Kundu¹, Abdullah Al Noman¹, Md Fakhruddin¹, Muttasim Billaha¹, Moniruzzaman Anik¹, Tanzil Hasan¹, Nikhil Tudu¹, Abdur Rahim¹, Farzana Mim⁴, Mohammad Jahidur Rahman Khan⁵

Affiliations

¹ Department of Microbiology, US-Bangla Medical College and Hospital, Narayanganj, BGD.
² Department of Gastroenterology and Hepatology, Ehime University Graduate School of Medicine, Toon City, JPN.
³ Molecular Diagnostics Laboratory, Bangabandhu Sheikh Mujib Medical College, Faridpur, BGD.
⁴ Department of Biochemistry and Molecular Biology, Jahangirnagar University, Dhaka, BGD.
⁵ Department of Microbiology, Shaheed Suhrawardy Medical College, Dhaka, BGD.

Abstract

Background: Self-collection of nasal swabs for the detection of SARS-CoV-2 RNA by reverse transcription-polymerase chain reaction (RT-PCR) would considerably increase the testing capability and decrease the risk of transmission among healthcare workers (HCW) and the use of personal protective equipment (PPE).

Objectives: This study aimed to evaluate the performance of self-collected nasal swabs compared with professionally collected nasopharyngeal (NP) swabs for detection of SARS-CoV-2 RNA by RT-PCR.

Materials and methods: We performed a cross-sectional study where the suspected cases of coronavirus disease 2019 (COVID-19) were instructed about the self-collection of nasal swabs from their mid-turbinate. The results were compared to a nasopharyngeal swab collected by a trained healthcare worker in the same patient at the same sitting.

Results: We enrolled 100 participants, of which, 69 (69%) were male and 31 (31%) were female. The median age of the study participant was 36 years. Of the participants, 58 (58%) were symptomatic, and the commonest clinical presentation was cough, which was present in 42 (42%) participants. Out of 100 samples, 31 (31%) professionally collected nasopharyngeal swabs and 28 (28%) self-collected nasal swabs were positive for SARS-CoV-2 by RT-PCR. Out of 31 professionally collected positive samples, three samples were negative in self-collection. Out of 28 self-collected positive samples, no sample was negative in the professional collection. The sensitivity and specificity of self-collected nasal swabs compared to professionally collected nasopharyngeal swabs were 90.32% and 100.00%, respectively. The sensitivity of self-collected nasal was 100% when the cycle threshold (Ct) value of the professionally collected NP swab was less than 30.

Conclusion: Our study showed that self-collected nasal swabs' sensitivities were similar to professionally collected NP swabs with a high viral load (low Ct value). Hence, this method could be used when the patient is symptomatic and come to the health providers in the early stage of COVID-19 illness.

Keywords: covid-19; nasal swab; nasopharyngeal swab; rt-pcr; sars-cov-2; self-collection.