The preventive and protective role of melatonin in SARS-CoV-2 infection: a retrospective study Molina Carballo, Antonio Jerez Calero, Antonio Emilio Fernández López, Luisa Augustín-Morales, María del Carmen Muñoz Hoyos, Antonio Agil Abdalla, Mhmad Ahmad This study has investigated the protective role of melatonin against SARS-CoV-2 infection. For this purpose, 62 adults were recruited who were in daily relatively high doses of melatonin intaking, with the particularity that they started taking it before the beginning of the COVID-19 pandemic and continued to present. A continuous validation process has been carried out with a series of questionnaires to identify the risk factors, whether they were contacts, were infected, if yes, the level of disease severity, need for treatment, hospitalization, etc. According to the dose of melatonin the individuals took/are taking, they were divided into two groups: a) those taking 20 mg (n = 27) and, b) those taking ≥ 40 mg (n = 32). For statistical analysis, the shi2 test and Fisher's exact test were used. The number of infected subjects with positive PCR was 7 (11.9%). Only one required medication, the rest had a very favorable clinical evolution, mild in three cases and asymptomatic in three others. While in their environment this percentage is 22.05% (chi2 = 2.928; p < 0.087). Melatonin offers a good safety profile, is well tolerated and can play an important role in the different levels of COVID-19 prevention. 2024-01-26T08:42:14Z 2024-01-26T08:42:14Z 2023 journal article https://hdl.handle.net/10481/87330 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ open access Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License