COVID-19 patients have a sustained, elevated Effectors T cells and Effector Memory T cells population
The environment established by an infection, both locally and systemically, can cause changes in general memory T cell populations [10]. We looked at how COVID-19 affected naive, effector, and memory CD4+ and CD8+ T cells. Over time, distinct variations in the CD4+ and CD8+ T populations of COVID-19 patients were detected (Table 3). The fraction of CD4+ naive T cells and CD4+ central memory cells decreased significantly with time when compared to the time of enrolment (Figure 2A & 2C). At 6-7 months after discharge from hospital, there was a considerable increase in the CD4+ effector and CD4+ effector memory T cell fractions compared to results obtained at the time of hospitalization (Figure 2B & 2D).