A compilation of coronavirus studies demonstrates the effectiveness of early treatment by hydroxychloroquine.<ref>https://www.researchgate.net/publication/344103059_Hydroxychloroquine_is_Effective_and_Safe_for_the_Treatment_of_COVID-19_and_May_be_Universally_Effective_When_Used_Early_Before_Hospitalization_A_Systematic_Review</ref>
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A compilation of coronavirus studies demonstrates the effectiveness of early treatment by hydroxychloroquine.<ref>https://c19study.com/</ref>