[Variability In Demographic And Clinical Characteristics Of Covid-19 Cases Between The First And Second Waves In...

Since the confirmation of the first case of SARS-CoV-2 in China in December 2019, all countries in the world have been affected by this pandemic. After one (1) year of the pandemic in Mali, two outbreaks were observed. The objective of this study was to characterize the demographic and clinical variability of cases between the two episodes.

This was a secondary analysis of data from patients with COVID-19 in Mali during the first and the second outbreaks. The anonymous list of all COVID-19 cases confirmed by RT-PCR was used. Pearson's and Student's Chi-square tests were performed with a significance level of 5%.

During the study period, 2567 and 4610 people were confirmed positive for SARS-CoV-2 respectively for the first and second epidemics with a similar average age (40.4 years ±17.6 for the first against 39.9 years ± 17.2 for the second). The male sex had a higher proportion in the two outbreaks but different between the waves (69% for the first outbreak and 60% for the second, p < 0.001). The proportion of symptomatic patients was significantly different between the two waves (6.2% for the first wave versus 13.1% for the second wave, p < 0.001). The proportions of cases by age group were significantly similar between the two waves (0-20 years: 10.1% vs 11.3%; 21-40 years: 46.3% vs 45.7%; 41-60 years: 28.2% vs 29.4%; Over 60: 15.4% vs 13.5%; p = 0.063). Death rate was higher in the first episode compared to the second (5.8% versus 4.3%; p = 0.003).

SARS-CoV-2 infection in Mali had a significant variation in symptomatology between the two waves, more highlighted in the second. The proportions of age groups of patients with COVID-19 did not vary between the two outbreaks. Death rate was higher in the first wave.