Efficacy of hydroxychloroquine in pre-exposure severe acute respiratory syndrome coronavirus 2 prophylaxis among high-risk healthcare workers: A multicenter study


1 Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences; Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

3 Department of Internal Medicine, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

4 Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

5 Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Science, Isfahan, Iran

6 Department of Medical Laboratory Science, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran


Background: Prophylaxis could be an established strategy to potentially prevent and control infectious diseases and should be considered in the coronavirus disease 2019 (COVID-19) pandemic. The present study aimed to assess the effectiveness of hydroxychloroquine as a prophylaxis treatment strategy in the reduction of the risk of COVID-19 among health professionals.
Materials and Methods: The health professionals were randomly assigned (1:1) to the control group without receiving any hydroxychloroquine as prophylaxis and the hydroxychloroquine group receiving a weekly hydroxychloroquine dose of 400 mg up to 12 weeks.
Results: A total of 146 health professionals were randomly enrolled in this study between August 11 and November 11 in 2020. Among the screened health professionals, 21 (14.6%) were infected with COVID-19 during the 12 weeks, and 14 (66.6%) out of the 21 health professionals were in the control group. Most participants with COVID-19 had mild symptoms (62%). In addition, 9.5% (n = 2) of the participants suffered from moderate disease and 28.5% were diagnosed with severe symptoms. In the hydroxychloroquine group, 5 (7.1%) and 2 (2.8%) participants were reported with mild and moderate symptoms of COVID-19, respectively, and 2 participants had moderate, 8 (10.9%) participants had mild symptoms, and 6 (8.2%) participants had severe symptoms in the control group, within 3 months. Severe symptoms of COVID-19 were not observed in the hydroxychloroquine group.
Conclusion: This study addressed the effect and benefit of hydroxychloroquine administration for the prevention of COVID-19 among health professionals. The improved perception of prophylaxis might highlight its important role in future COVID-19 outbreaks to prevent hospital transmission, which is a major route of spread.


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