We observed lower median proportion of naïve CD8+ T cells in COVID-19 X-ray (+) patients than in COVID-19 X-ray (−) patients and healthy control, without significant differences between COVID-19 X-ray (+) patients and COVID-19 X-ray (−) patients (15.4% vs. 39.2% vs. 42.4%, p = 0.0029). Here, CD8A is linked to COVID-19.