COVID-19 in Latin America: Contrasting phylodynamic inference with epidemiological surveillance.

Rojas-Gallardo, D. M.; Garzon-Castano, S. C.; Millan, N.; Jimenez-Posada, E. V.; Cardona-Ospina, J. A.

Introduction: SARS-CoV-2 infection has represented the one of the largest challenges for humanity. This virus was first detected in Latin America and the Caribbean (LAC) in Brazil in February 26, 2020 and it has revealed important gaps in infectious disease surveillance that must be covered. Phylodynamic analysis is a tool that can help to monitor and adapt traditional surveillance measures in order to cover those. Therefore, this work aims to contrast data driven from epidemiologic surveillance in LAC with parameters inferred from phylodynamic analysis of reported genomes of SARS-CoV-2 across different LAC countries Methods: We obtained epidemiological data from daily reports provided by European Centre for Disease Prevention and Control up to 13th May, 2020. We estimated Effective Reproductive Number (Re) and calculated epidemic curves with exponential growth (EG) and maximum likelihood (ML) methods. SARS-CoV-2 phylodynamic in Latin-American was analyzed using sequences reported in GISAID for Central and South America up to May 13th 2020. Sequences were aligned, and ML phylogeny was constructed. Coalescent model Birth Death SIR (serial) was run, and SIR trajectories from the birth-death SIR model were plotted. Results: A total of 404,448 cases were reported up to 13th May 2020. Overall reproduction number for Latin America, estimated through the EG and ML methods, were 1.424 (IC95% 1.422 to 1.426) and 1.305 (IC95% 1.299 to 1.311) respectively. Phylodynamic analysis for Latin America showed an overall Re of 1.27 (IC95% 1.07 to 1.49). We did not find statistically significant differences between epidemiological and phylodynamic data at the cut-off time, except for Brazil. Discussion: Our results support that epidemiological and genomic surveillance are two complementary approaches. Evidence suggests that even with a low number of sequences proper estimations of Re could be performed. We suggest that countries, especially developing countries, should consider to add genomic surveillance to their systems for monitoring and adapting epidemiological surveillance of SARS-CoV-2.