Evaluation of PCR Negativity in Respiratory Specimens of COVID-19 Patients After Hydroxychloroquine and/or Favipiravir Treatment

Objective: We evaluated PCR negativity in oropharyngeal and nasopharyngeal secretions of COVID-19 patients at the end of hydroxychloroquine and/or favipiravir treatments.Methods: Study inclusion criteria were being hospitalized, being older than 18 years, PCR positivity in oropharyngeal and nasopharyngeal secretions and being tested for SARS CoV-2-RNA PCR after treatment. Initially hydroxychloroquine treatment (group 1) was administered to the patients according to COVID-19 guide of Health Ministry. Favipiravir (group 2) alone or in combination with hydroxychloroquine (group 3) was administered to patients who were unresponsive to hydroxychloroquine or had severe pneumonia or were admitted to intensive care unit. Control respiratory specimens were taken no earlier than 24 hours, after the end of therapy. Repeated tests with 24-48-hour intervals were performed in patients with still positive PCR test results. The detection of SARS CoV-2-RNA was made by real-time PCR.Results: The study group included 492 patients who received treatment. Mean duration of symptoms was similar among three groups. PCR negativity rate was 52.8% in the specimens taken 24 hours after the end of treatment. PCR negativity rates was 27.9% (200/492) in 48 hours after the end of treatment, %13.8 (123/492) in 72nd hour and %3.8 (80/492) in 96th hour. The ratios of PCR negativity for all specimen days were similar in three groups. There was no statistically significant difference between the groups for time to PCR negativity from the date of positivity and after the end of treatment. We determined that early or late treatment did not make a difference in terms PCR negativity time.Conclusion: No difference was found in terms of the ratios of PCR negativity or time for negativity in oropharyngeal and/or nasopharyngeal specimens taken after the end of treatment in COVID-19 patients receiving hydroxychloro-quine and/or favipiravir treatment.