Time to Negative Test Result among Patients with COVID-19: A Retrospective Study

Background: Coronavirus disease 2019 (COVID-19) is a public health emergency, however, there is still limited data on the length of infectiveness of the disease especially in Nigeria. The aim of this study was to ascertain the duration of viral shedding in patients testing positive for COVID-19 to deduce the appropriate time to discharge SAR-CoV2 Positive patients from follow-up by the healthcare team in our setting.

Methods: In this retrospective study, time to a negative test result in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was evaluated in a cohort of 490 patients who tested positive at the Satellite Molecular Laboratory of the Rivers State University Teaching Hospital, Port Harcourt.

Results: The mean age of the 490 patients was 39.8 ± 13.9. There were 379 (77.3%) males and 111 (22.7%) females. The mean duration of SARS-CoV-2 RNA detection was approximately 15±2 days. When comparing patients who were tested twice with those who were tested more than two times, a significant difference between mean time to a negative result and the number of tests done was identified (t= P-Value = <0.001).

Conclusions: Findings from this study show that the average time of transition from a positive to negative PCR test result was approximately 15 days, regardless of the gender. This can provide an estimated duration of hospital stay among COVID-19 patients to prevent unnecessary healthcare costs and minimize re-infection.