Infection and Drug Resistance (Dec 2022)
A Pilot Study of 0.4% Povidone-Iodine Nasal Spray to Eradicate SARS-CoV-2 in the Nasopharynx
Abstract
Rujipas Sirijatuphat,1 Amorn Leelarasamee,1,2 Thanapat Puangpet,3 Arunee Thitithanyanont4 1Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 2Faculty of Medicine, Siam University, Bangkok, Thailand; 3Samut Sakhon Hospital, Samut Sakhon, Thailand; 4Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, ThailandCorrespondence: Amorn Leelarasamee, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Thanon Wang Lang, Siriraj, Bangkoknoi, Bangkok, 10700, Thailand, Tel/Fax +66 2 419 7783, Email [email protected]: This study aimed to evaluate the virucidal efficacy of 0.4% povidone-iodine (PVP-I) nasal spray against SARS-CoV-2 in the patients’ nasopharynx at 3 minutes and 4 hours after PVP-I exposure.Patients and Methods: The study was an open-label, before and after design, single-arm pilot study of adult patients with RT-PCR-confirmed COVID-19 within 24 hours. All patients received three puffs of 0.4% PVP-I nasal spray in each nostril. Nasopharyngeal (NP) swabs were collected before the PVP-I spray (baseline, left NP samples), and at 3 minutes (left and right NP samples) and 4 hours post-PVP-I spray (right NP samples). All swabs were coded to blind assessors and transported to diagnostic laboratory and tested by RT-PCR and cultured to measure the viable SARS-CoV-2 within 24 hours after collection.Results: Fourteen patients were enrolled but viable SARS-CoV-2 was cultured from 12 patients (85.7%). The median viral titer at baseline was 3.5 log TCID50/mL (IQR 2.8– 4.0 log TCID50/mL). At 3 minutes post-PVP-I spray via the left nostril, viral titers were reduced in 8 patients (66.7%). At 3 minutes post-PVP-I, the median viral titer was 3.4 log TCID50/mL (IQR 1.8– 4.4 log TCID50/mL) (P=0.162). At 4 hours post-PVP-I spray via the right nostril, 6 of 11 patients (54.5%) had either the same or minimal change in viral titers. The median viral titer 3 minutes post-PVP-I spray was 2.7 log TCID50/mL (IQR 2.0– 3.9 log TCID50/mL). Four hours post-PVP-I spray the median titer was 2.8 log TCID50/mL (IQR 2.2– 3.9 log TCID50/mL) (P=0.704). No adverse effects of 0.4% PVP-I nasal spray were detected.Conclusion: The 0.4% PVP-I nasal spray demonstrated minimal virucidal efficacy at 3 minutes post-exposure. At 4 hours post-exposure, the viral titer was considerably unchanged from baseline in 10 cases. The 0.4% PVP-I nasal spray showed poor virucidal activity and is unlikely to reduce transmission of SARS-CoV-2 in prophylaxis use.Keywords: povidone iodine, COVID-19, SARS-CoV-2, viral eradication, viral culture, nasopharyngeal swab
