Patterns of RT-PCR Test Conversion and Implications on Time of Discharge in a District Hospital and a COVID-19 Care Centre in Pali, Rajasthan, India

Cureus. 2022 Jul 27;14(7):e27325. doi: 10.7759/cureus.27325. eCollection 2022 Jul.

Abstract

Introduction Although coronavirus disease 2019 (COVID-19) first appeared in 2019, the symptoms are similar to common viral illnesses, and if undiagnosed or there is a delay in treatment, it may prove fatal because of the virus's propensity to attack the respiratory and cardiovascular system. The antigenic conversion status of reverse transcription-polymerase chain reaction (RT-PCR) was an important criterion for discharge among the COVID-19 patients of the two hospitals in the study. Aim The aim of the study was to assess the time taken to antigenic conversion from positive to negative in RT-PCR test for COVID-19 done on patients admitted to the two hospitals where the study took place. Materials and methods A prospective cross-sectional study with repeated sampling for antigenic conversion by RT-PCR was done on 117 patients of different age groups admitted to Bangur Hospital and Agarsen Bhavan in Pali, Rajasthan, India, from April 27 to June 30, 2020. Pharyngeal and nasal swabs were analyzed by real-time RT-PCR for COVID-19 infection. The patients' first positive sample was taken as "zero sample". If the repeat sample taken on the fifth day was positive, sampling was repeated after 48 hours on consecutive days 7, 9, 11, 13, and 15 of admission till the RT-PCR test returned negative. Results Among the 117 patients, 92 (78.63%) were treated as mild, 10 (8.54%) were moderately severe, and 15 (12.82%) were very severe requiring ICU care. The median rate of conversion of RT-PCR test (positive to negative) from the day of admission was quite variable as five patients converted to negative by RT-PCR test on day seven of admission, one on day eight of admission, 26 on day nine, 30 on day 10, five on day 11, 13 on day 12, 10 on day 13, 11 on day 14, five on day 15, six on day 16, three on day 17, and one on day 18 of admission. Conclusion The study proved that follow-up of patients, prompt and comprehensive treatment, and repeated sampling ensures fast recovery with implications on time to discharge of such patients in a pandemic. The study justified and heralds the message that the inherent immunity of an individual corresponds to the time taken to conversion from positive to negative in the RT-PCR test.

Keywords: antigenic; conversion; coronavirus disease; covid-19; district hospital; rt-pcr.