CD8A and hemorrhagic fever with renal syndrome: Our data identified a notable increase in the proportions of CD8+ Tem and B cells in severe HFRS patients compared to those with moderate symptoms, whereas the frequencies of CD56dim NK cells were found to be decreased in severe cases relative to their moderate counterparts (Figure 4, Supplementary Figures S5-S7).These findings enable early risk stratification to facilitate timely intervention for potentially severe cases.