Objective: To describe the characteristics of COVID-19 patients seen in March-April and June-August 2020 in Marseille, France with the aim to investigate possible changes in the disease between these two time periods.
Methods: Demographics, hospitalization rate, transfer to intensive care unit (ICU), lethality, clinical and biological parameters were investigated.
Results: Compared to those seen in March-April, COVID-19 patients seen in June-August were significantly younger (39.2 vs. 45.3 years), more likely to be male (52.9% vs. 45.6%), and less likely to be hospitalized (10.7 vs. 18.0%), to be transferred to ICU (0.9% vs. 1.8%) and to die (0.1% vs. 1.1%). Their mean fibrinogen and D-dimer blood levels were lower (1.0 vs. 1.5 g/L and 0.6 vs. 1.1 μg/mL, respectively). By contrast, their viral load was higher (cycle threshold ≤16 = 5.1% vs. 3.7%).
Conclusions: Patients in the two periods did not present marked age and sex differences, but markers of severity were undoubtedly less prevalent in the summer period, associating with a 10 times decrease in the lethality rate.
Keywords: COVID-19; Lethality; Seasonality; Severity markers.
Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.