Fig. 2

Dynamic variations in cell counts of total WBCs, total lymphocytes, and lymphocyte subsets in patients with severe COVID-19 and severe influenza A at weeks (W) 1, 2, 3, and 4 during the course of illness. a–b Box plots illustrating percentages of total WBCs and total lymphocytes in different groups at different times. Kruskal–Wallis test followed by Dunn’s multiple comparisons test or one-way analysis of variance (ANOVA) test followed by Tukey’s multiple comparisons test was performed to determine significant differences between the groups. c–f Box plots illustrating total cell counts of T lymphocyte subsets in different groups at different times. Spearman’s nonparametric test was used to test for correlations. * P < 0.05,** P < 0.01, *** P < 0.001 were considered significant