Jaime Berumen et al. Medical Research Archives vol 8 issue 9. Medical Research Archives RESEARCH ARTICLE Trends of SARS-Cov-2 infection in 67 countries: Role of climate zone, temperature, humidity, and curve behavior of cumulative frequency on duplication time Authors Jaime Berumen, MD1, Max J. Schmulson2, Guadalupe Guerrero3, Elizabeth Barrera1, Jorge Larriva- Sahd4, Gustavo Olaiz5, Rebeca García-Leyva1, Rosa María Wong-Chew6, Miguel Betancourt- Cravioto7, Hector Gallardo7, Germán Fajardo-Dolci8, Roberto Tapia-Conyer7 Affiliations 1Unidad de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico. 2Laboratorio de Hígado, Páncreas y Motilidad (HIPAM)-Unidad de Investigación en Medicina Experimental, Facultad de Medicina-Universidad Nacional Autónoma de México (UNAM). 3Hospital General de México, Dr. Eduardo Liceaga, Mexico City, Mexico. 4Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Campus Juriquilla, Querétaro Mexico 5Centro de Investigación en Políticas, Población y Salud, Facultad de Medicina, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico. 6División de Investigación, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico 7Fundación Carlos Slim, Mexico City, Mexico 8Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico *Correspondence Jaime Berumen, MD E-mail:
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[email protected] Copyright 2020 KEI Journals. All Rights Reserved Jaime Berumen et al. Medical Research Archives vol 8 issue 9. September 2020 Page 2 of 22 Abstract Aims. To analyze the role of temperature, humidity, date of first case diagnosed (DFC) and behavior of the growth-curve of cumulative frequency (CF) [number of days to rise (DCS) and reach the first 100 cases (D100), and the difference between them (ΔDD)] with the doubling time (Td) of COVID-19 cases in 67 countries grouped by climate zone.