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Persistent Positivity of Reverse Transcriptase-Polymerase Chain Reaction Test among Patients with COVID-19 in Rural
Narayani Maharjan1, Niresh Thapa2, Bibek Pun Magar3
1Program & Department of Clinical Laboratory Medicine, Center for Gene Diagnosis, Zhongnan Hospital of Wuhan University, Wuhan, China and Department of Molecular Laboratory, Karnali Academy of Health Sciences, Jumla, Nepal.
Introduction:
The persistence positivity detected for severe acute respiratory syndrome coronavirus 2 ribonucleic acid by real-time reverse transcriptase-polymerase chain reaction test in asymptomatic coronavirus disease 2019 positive patients has attracted a lot of attention. There is limited data on the duration of viral shedding. We aimed to determine the proportion of coronavirus disease patients with persistent positivity of real-time reverse transcriptase-polymerase chain reaction test in a teaching hospital of Nepal.
Methods:
A descriptive cross-sectional study was conducted using medical records from May to September 2020 in a teaching hospital of Nepal. The study was approved by the Institutional Review Committee of Karnali Academy of Health Sciences (Reference no 077/078/03). Convenient sampling method was used. Data was analysed by Statistical Package for the Social Sciences. Point estimate at 90% Confidence Interval was calculated along with frequency and proportion for binary data.
Results:
Of the total 95 cases, 9 (9.5%) cases (4.6-14.4 at 90% Confidence Interval), were repeat positive after achieving the first negative. The mean day required of achieving the last negative for the repeat positive group was 62.11±3.95, range (60-70 days). The mean time duration for the virus shedding was found to be 20.43±12.19 days (range 7-60 days) after the first positive test result.
Conclusions:
This study concludes that there might be a persistent positivity of the polymerase chain reaction test among patients with COVID-19. The majority of the patients were test positive for 8-14 days, and some were positive till 60-70 days.

